Defining and Measuring Sexual Orientations for Research
INTRODUCTION
Conceptually defining populations, such as those defined by race and ethnicity, and developing methods to operationally identify members of those populations, have continually challenged researchers (LaVeist, 2002). Today, as scientists begin to treat sexual orientation as a demographic variable like race and ethnicity, it is important to critically examine and clarify our conceptualizations of sexual orientation as well as critically examine measures used to operationally identifying the sexual orientation of research subjects.
There is much evidence that researchers are often confused as to what they are studying when
they assess sexual orientations in their research. Several literature reviews have found that
researchers' conceptual definitions of these populations are rarely included in reports of their
research and, when they are included, they often differ theoretically. Further, the methods used to measure sexual orientations in these studies do not always correspond with the most common conceptualizations of sexual orientation (Shively, et al. 1985; Sell and Petrulio, 1995; Chang and Katayama, 1996). Sell and Petrulio recommended that researchers work to develop uniform conceptual definitions of terms used to label sexual orientations and that uniform methods of operationally identifying sexual orientations be agreed upon for use in research studies. They believe it is imperative that researchers who claim to be studying these populations begin to clarify what it is they are actually studying and recognize more explicitly the effect their research methods have upon their findings. Sell and Petrulio’s recommendation’s echo the much earlier work of Henry who conducted one of the most detailed studies of homosexuality ever produced (Henry, 1941). Henry concluded that: “Unless the word homosexual is clearly defined, objective discussion regarding it is futile, and misunderstanding and erroneous conclusions are inevitable (Henry, 1955).”
To clear up some of this confusion, this chapter reviews and critiques conceptual definitions of sexual orientations and the measures used to identify and classify subjects' sexual orientations that have been proposed and used by scientists and laypersons since the 1860s in Europe and the United States. It was in the 1860s that the formal study of sexual orientations was founded by Ulrichs. It is hoped that this review will encourage researchers to be more critical of the methods they use to identify and label the sexual orientation of research subjects.
CONCEPTUAL DEFINITIONS OF SEXUAL ORIENTATION
Many different terms and definitions have been proposed over the last 140 years to describe the sexual orientation of study subjects. One of the earliest and most important sexual orientation classification schemes was proposed by Ulrichs in a series of pamphlets he privately published in the 1860s (Carpenter, 1908; Ulrichs, 1994). Ulrichs’ scheme, which was only intended to describe males, separated them into three basic categories: dionings, urnings, and uranodionings (see Karl Ulrichs). These terms were derived from a speech by Pausanias in Plato's Symposium in which Pausanias refers to Uranus (heaven) (Plato. The Symposium and The Phaedrus. State of New York Press, Albany, NY, 1993). Arguably these categories directly correspond with the categories used today: heterosexual, homosexual and bisexual (Cory, 1951). Homosexual women, who were largely ignored by early researchers, were referred to as urningins and heterosexual women were referred to as dioningins by Ulrichs (Bullough, 1990).
Mayne, a follower of Ulrichs, provided a definition of an urning in the first major work on
homosexuality to be written by an American. He defined an urning as “a human being that is
more or less perfectly, even distinctly, masculine in physique; often a virile type of fine
intellectual, oral and aesthetic sensibilities: but who, through an inborn or later-developed
preference feels sexual passion for the male human species. His sexual preference may quite
exclude any desire for the female sex: or may exist concurrently with that instinct (Mayne, 1908).” Mayne’s definition also encompasses male uranodionings by stating that desire for the female sex may exist concurrently.
In addition to his effect on Mayne, Ulrichs had a profound influence on the works of many early researchers including Westphal (1869), Symonds (1883, 1891), Krafft-Ebing (1886), Moll (1891), Carpenter (1894, 1908), Ellis and Symonds (1896), and Hirschfeld (1914). Further, through the works of these researchers, Ulrichs is credited with influencing Freud and Jung (Bullough, 1994). While they may differ significantly, the conceptualizations of sexual orientation most often cited today generally have their root in the works of Ulrichs.
Even the terms “homosexuality” and “heterosexuality,” which Ulrichs did not prefer, have direct links to him. The term homosexual is an inappropriate combination of Greek and Latin that disturbed many early researchers who wanted it replaced, but recognized that it was too deeply rooted in the literature by the time they arrived on the scene (Robinson, 1936; Kinsey et at, 1948). The term homosexual may have been introduced into English by Symonds in his first edition of A Problem of Modern Ethics in 1891 (Boswell, 1980). These terms homosexuality and heterosexuality first appeared in a letter to Ulrichs drafted on May 6, 1868, from Benkert, a German-Hungarian physician and writer (Ulrichs, 1994). Later, Benkert outlined his definition of homosexuality in a pamphlet published in 1869. His definition read:
In addition to the normal sexual urge in man and woman, Nature in her sovereign mood has endowed at birth certain male and female individuals with the homosexual urge, thus placing them in a sexual bondage which renders them physically and psychically incapable-even with the best intention-of normal erection. This urge creates in advance a direct horror of the opposite sexual (sic) and the victim of this passion finds it impossible to suppress the feeling which individuals of his own sex exercise upon him (cited in Robinson, 1936).
Today the terms heterosexual (straight), homosexual (gay and lesbian), and bisexual are the most commonly used terms by researchers to describe sexual orientations (Shively et al., 1985; Sell and Petrulio, 1995). While not many other terms have been proposed to describe heterosexuality or bisexuality, an overabundance of terms have been used by researchers to describe homosexuality, including uranianism, homogenic love, contrasexuality, homo-erotism, similsexualism, tribadism, sexual inversion, intersexuality, transexuality, third sex, and psychosexual hermaphroditism (Ulrichs, 1994; Moll, 1891; Carpenter, 1894, 1908; Ellis and Symonds, 1896; Mayne, 1908; Kinsey et al., 1948, 1953). Even today terms take on new meaning and importance for describing sexual orientations. The term queer for example is defined by Legman in 1941 as: “Homosexual; more often used of male homosexuals than of Lesbians. As an adjective it is the most common in use in America.” At the time Legman wrote, the term was slang and used pejoratively. Currently, the term still means “homosexual,” but is frequently used nonpejoratively in scholarly works (for example, see Signorile, 1993; Breit et al, 1994; Feinberg, 1994; Goldberg, 1994; Packard and Packard, 2005). Today's preferred terms and the term “sexual orientation” itself have a wide variety' of definitions in the literature but these generally comprise one or both of two components: a “psychological” component and a “behavioral” component. Not all definitions include both of these components, and as are discussed in detail below, definitions that include both components use either the conjunction “and” or “or” to join them.
Mayne's (1908) definition of the term Urning and Benkert's of the term homosexual (Robinson, 1936) only include a description of the psychological state. Mayne discussed how an individual's feelings of sexual passion determine their sexual orientation while Benkert talked of an “urge.” Ellis, one of the most important writers on sexuality in late 19th and early 20th century England, also only talked of a psychological entity which he described as “sexual instinct.” Ellis defined homosexuality as “sexual instinct turned by inborn constitutional abnormality toward persons of the same sex” (Ellis and Symonds, 1896). Ellis used the term “sexual inversion” at the time this definition was provided, but in later versions of his work substituted the term “homosexuality” (Ellis and Symonds, 1896; Ellis, 1942). Two of the earliest medical journal articles about homosexuality to appear in the English language provide a definition that, like the other early definitions, does not discuss sexual behavior. Their definition, which in both cases is a translation of Westphal's German definition describes homosexuals as persons that: “as a result of their inborn nature felt themselves drawn by sexual desire to male individuals exclusively” (Blumer, 1882; Shaw & Ferris, 1883).
These definitions and other early ones generally omit any discussion of behavior (and in
particular sexual behavior), except to say that the thought of it with the other sex is repulsive or horrifying to the homosexual. Another definition of this type was provided by Forel (1924) in his popular book The Sexual Question. Forel states “However shocking or absurd the aberrations of the sexual appetite and its irradiations may be, of which we have spoken hitherto, they are at any rate derived from originally normal intercourse with adults of the opposite sex. Those we have now to deal with are distinguished by the fact that not only the appetite itself, but all its psychic irradiations are directed to the same sex as the perverted individual, the latter being horrified at the idea of genital contact with the opposite sex, quite as much as a normal man is horrified at the idea of homosexual union.” Krafft-Ebing, like his contemporaries, even makes the point to exclude behavior front the diagnosis of homosexuality. Krafft-Ebing (1886) stated that “the determining factor here is the demonstration of perverse feelings for the same sex; not the proof of sexual acts with the same sex. These two phenomena must not be confounded with each other.”
More recent definitions often include both components. For example LeVay (1993) defined sexual orientation as “the direction of sexual feelings or behavior, toward individuals of the opposite sex (heterosexuality), the same sex (homosexuality), or some combination of the two (bisexuality),” and Weinrich (1994) defined homosexuality “either (1) as a genital act or (2) as a long-term sexuoerotic status.” Here the psychological states referred to are “sexual feelings” and “sexuoerotic status,” and the behavioral outcome is “sexual behavior” as referred to by LeVay and a “genital act” as referred to by Weinrich. The psychological and behavioral components in both definitions are joined by “or” signifying that either one can be used to assess sexual orientation.
In A Descriptive Dictionary and Atlas of Sexology (Francoeur et al, 1991), homosexuality is
broadly defined as “the occurrence or existence of sexual attraction, interest and genitally
intimate activity between an individual and other members of the same gender.” Here (the psychological components are “sexual attraction” and “interest” and the behavioral outcome is described as “genitally intimate activity.” Unlike the definitions of LeVay (1993) and Weinrich (1994), this definition joins the two components with the conjunction “and.” Using the conjunction “and” makes it unclear as to whether both components are necessary for the assignment of sexual orientation classifications.
At the other extreme from the early definitions provided by Mayne and Benkert are definitions that only include discussions of the behavioral component. For example, Stedman's Medical Dictionary (1982) defined homosexuality as “sexual behavior, including sexual congress, between individuals of the same sex, especially past puberty.” Here the psychological component does not seem to hold much if any importance for the assessment of sexual orientation. Beach (1950) is emphatic about only including sexual behavior in the definition of sexual orientation in his critique of the first English language translation of Gide's defense of homosexuality, Corydon. Beach (1950) states that “the term (homosexuality) means different things to different people . . . it is preferable to set forth the significance of the term as used in this discussion. Homosexuality refers exclusively to overt behavior between two individuals of the same sex. The behavior must be patently sexual, involving erotic arousal and, in most instances at least, resulting in the satisfaction of the sexual urge.” According to Diamond (1993), it is this type of definition that is favored by researchers determining the size of the “homosexual” population in various countries. In the studies reviewed by Diamond, while all used some assessment of sexual behavior to determine the prevalence of sexual orientations, none used any assessment of a psychological
state (such as sexual attraction).
Thus far I have discussed the two definitional components of sexual orientation as if the
components themselves were uniform across definitions, but as is evident in the examples
already provided, there are important variations. Psychological components of definitions may include the terms “sexual passion,” “sexual urge ... .. sexual feelings,” “sexual attraction,” “sexual interest,” “sexual arousal,” “sexual desire,” “affectional preference,” “sexual instinct,” “sexual orientation identity,” and “sexual preference.” “Sexual preference” has been used as a substitute for the term “sexual orientation,” but Gonsiorek and Weinrich (1991) believe it “is misleading as it assumes conscious or deliberate choice and may trivialize the depth of the psychological processes involved.” They therefore recommend the term sexual orientation because most research findings indicate that homosexual feelings are a basic part of an individual's psyche and are established much earlier than conscious choice would indicate.” Each of these terms may have a distinct meaning and not necessarily be indicative of the same phenomenon. That is, different terms in definitions may be describing slightly different phenomena despite the similar label for that phenomena.
Similarly, the behavioral component varies between definitions. Behavior can be stated simply as “sexual behavior” or it can be described, for example, as “genital activity,” “sexual intercourse,” “sexual contact,” or “sexual contact that achieves orgasm.” Each one of these presents further challenges for researchers. That is, how do we define each of these terms within the definition itself and how would we operationalize them for measurement?
Obviously definitions and preferred terms vary significantly from researcher to researcher and across time. While, it is not possible from this review to say one definition or set of terms is “better” than another, it is possible to make a few modest recommendations. First, all researchers who intend to collect sexual orientation data should dedicate time to choosing one of the definitions described here or developing their own definition before they begin their research. And second, researchers should make the terms and definitions they are using explicit when discussing research studies and findings. In the next section the operational measurement of sexual orientation is reviewed.
MEASURES OF SEXUAL ORIENTATION
As was demonstrated above, conceptualizations of sexual orientation vary dramatically between researchers. Measures of sexual orientation, as will be shown below, vary widely as well. However, this variation, like the variation in definitions, provides important insight to modern researchers.
Some of the earliest reports of assessing sexual orientation are found in the documents of the
Western Church, which encouraged individuals to confess their sins. In particular, religious
documents show the Church's concern with asking sensitive questions about such topics as
sodomy. These documents instructed priests in the 1500s “not to show amazement; exhibit a
contorted face; show revulsion (no matter what enormities are confessed) rebuke the penitent; or exclaim ‘Oh, what vile sins!’” when discussing sensitive subjects (Lee, 1993; Tentler, 1977).
De Pareja, who went to Florida as a missionary to the Timucua Indians in 1595, outlined specific questions to identify Sodomites in his book, Confessionario (Katz, 1992). These questions included:
1. Have you had intercourse with another man?
2. Or have you gone around trying out or making fun in order to do that? (Katz, 1992).
Pareja further provided questions to be asked of boys who may have committed sodomy including the following:
3. Has someone been investigating you from behind?
4. Did you consummate the act? (Katz, 1992).
Several centuries later, Ulrichs, in his series of pamphlets in the 1860s, outlined a set of
questions that could be asked to determine if a man was an Urning (Ulrichs, 1994). These
questions included:
1. Does he feel for males and only for males a passionate yearning of love, be it gushing and
gentle, or fiery and sensual?
2. Does he feel horror at sexual contact with women? This horror may not always be found but when it is found, it is decisive.
3. Does he experience a beneficial magnetic current when making contact with a male body in its prime?
4. Does the excitement of attraction find its apex in the male sexual organs?
Mayne (1908) also outlined a series of several hundred questions for the personal diagnosis of Urnings and Urningins. These questions include:
1. At what age did your sexual desire show itself distinctly?
2. Did it direct itself at first most to the male or to the female sex? Or did it hesitate awhile
between both?
3. Is the instinct unvaryingly toward the male or female sex now? Or do you take pleasure (or
would you experience it) with now a man, now a woman?
4. Do you give way to it rather mentally or physically? Or are both in equal measure?
5. Is the similsexual desire constant, periodic or irregularly felt?
6. In dreams, do you have visions of sexual relations with men or women, the more frequently and ardently?
The respondents to Pareja's, Ulrichs', and Mayne's questions were expected to be able to provide a yes or no answer. That is, the person was either categorized as a “Sodomite,” “Urning,” or “Urningin,” or not. This simple categorical scheme for the classification of sexual orientations remains the dominant one used by researchers today. That is, subjects are classified as homosexual or heterosexual based upon their sexual orientation identity or sexual behavior (Sell and Petrulio, 1995). In major health surveys, the state of the art question to assess sexual orientations, when only one question can be asked, is (Miller, 2002):
Which of the following best describes how you think of yourself? 1) Straight or Heterosexual, 2) Gay or Lesbian, 3) Bisexual, 4) Don’t know/Not Sure.
Despite this focus on single question measures, more sophisticated measures of sexual
orientation have been proposed over the last 50 years as researchers have encountered or
discovered the limitations of simple categorical measures. The most important of these
measures are reviewed below.
The most influential scale to be proposed during these years was put forth by Kinsey et al. 1948, 1953 in their reports on sexual behavior in the human male and female. Kinsey et al. proposed a bipolar scale that allowed for a continuum between “exclusive heterosexuality” and “exclusive homosexuality (see Kinsey Scale).” Kinsey et al. provided the following important justifications for their decision to depart from the dichotomous measures of his predecessors:
The world is not to be divided into sheep and goats. Not all things are black nor all things white. It is a fundamental of taxonomy that nature rarely deals with discrete categories. Only the human mind invents categories and tries to force facts into separated pigeon-holes. The living world is a continuum in each and every one of its aspects. The sooner we learn this concerning human sexual behavior the sooner we shall reach a sound understanding of the realities of sex (Kinsey et al., 1948).
It is characteristic of the human mind that it tries to dichotomize in its classification of phenomena. Things are either so, or they are not so. Sexual behavior is either normal or abnormal, socially acceptable or unacceptable, heterosexual or homosexual; and many persons do not want to believe that there are gradations in these matters from one to the other extreme (Kinsey et al., 1953).
One of the more striking facts about these statements is that Kinsey had been trained as a
taxonomist (Weinrich, 1990). It had been much of his life work to develop such dichotomous, yes or no, classifications as he so easily dismissed here. But by dismissing dichotomous
classifications and developing a bipolar continuous model, a new way of measuring sexual
orientation, providing a new perspective on sexuality, was created. However, as it forces subjects into one of seven categories, the Kinsey Scale is not a true continuum. This is fortunate in some ways because the seven points are difficult to assign and if there were an infinite number of points the task would be that much more difficult.
Masters and Johnson (1979), in a major study of homosexuality, provide the following discussion about the difficulty of assigning Kinsey ratings:
There was also concern in arbitrarily selecting the specific classification of Kinsey grades 2 through 4 for any individual who had had a large number of both homosexual and heterosexual experiences. The ratings were assigned by the research team after detailed history-taking, but it is difficult for any individual to be fully objective in assessing the amount of his or her heterosexual versus homosexual experience when there has been a considerable amount of both types of interaction. Some of these preferences ratings might well be subject to different interpretation by other health-care professionals.
Masters and Johnson further state that:
Kinsey 3 classification was the most difficult to assign of the ratings. Relative equality in any form of diverse physical activity is hard to establish. Particularly was this so when the interviewer, in attempting to separate mature sexual experience into its homosexual and heterosexual components, was faced with a history of a multiplicity of partners of either sex. The problem was augmented by the subjects' frequently vague recall of the average number of sexual interactions with each partner.
It is evident from these reports that it is difficult to determine the relative importance of the
heterosexual and homosexual in a person's history when using the Kinsey Scale, but this is only one of several concerns often expressed by researchers about this scale. A second concern with the Kinsey Scale is that it lumps individuals who are significantly different based upon different aspects or dimensions of sexuality into the same categories (Weinrich et al., 1993; Weinberg et al., 1994). In fact, Kinsey himself took two dimensions of sexual orientation, “overt sexual experience” and “psychosexual reactions,” into account when applying his scale. Kinsey el al. (1948) provides the following discussion of these two dimensions and how they were used in the assessment of sexual orientation:
It will be observed that the rating which an individual receives has a dual basis. It takes into account his overt sexual experience and/or his psychosexual reactions. In the majority of instances the two aspects of the history parallel but sometimes they are not in accord. In the latter case, the rating of an individual must be based upon an evaluation of the relative importance of the overt and the psychic in his history (Kinsey et al., 1948).
It can be argued that valuable information was lost by collapsing these two separate values into one final score. A common solution that avoids the loss of information is to assess dimensions of sexual orientation separately and report the scores independently as Kinsey could have easily done. When this approach is taken, the two most commonly assessed aspects of sexual orientation are sexual behavior and sexual fantasies. These two dimensions are most likely chosen because they correspond with the two dimensions, “overt sexual experience” and “psychosexual reaction” proposed by Kinsey (Kinsey 1948; Sell and Petrulio 1995). They may also be chosen because they reflect the behavioral and psychological components of definitions as discussed in the previous section. But sexual behavior and sexual fantasies are not the only dimensions that may be considered. For example, Klein et al. (1985) proposed in the Klein Sexual Orientation Grid (KSOG) the assessment of seven dimensions including sexual attraction, sexual behavior, sexual fantasies, emotional preference, social preference, self identification and heterosexual/homosexual life-style (see Klein Grid). A concern with assessing multiple dimensions is that as each is added the overall scale becomes more burdensome and less practical for many research purposes. Researchers therefore tend to limit the number of assessed dimensions.
Diamond (1993) reviewed several research studies in which sexual behavior and sexual fantasies were assessed on the Kinsey Scale. He reported that this is somewhat common in studies of specific gay populations. In the studies reviewed, there appears to be a high but not perfect correlation between reported sexual behavior and fantasy. The value of measuring these two dimensions for the assessment of sexual orientation or any other dimension has not been well determined (Ross et al., 2003).
Only a few published studies have explicitly examined the value of studying more than one
dimension of sexual orientation. Weinrich et al. (1993) found, using factor analysis, that all of the dimensions of sexual orientation proposed by Klein in the KSOG seem to be measuring the same construct. That is, all of the dimensions load on a first factor which accounts for most of the variance. However, they further find in the two samples that were studied that a second factor emerged containing time dimensions of social and emotional preferences, suggesting that the social and emotional preference dimensions may have also been mmeasuring something other than sexual orientation.
Another study, The National Health and Social Life Survey, demonstrated that sexual attraction, sexual behavior and sexual orientation identity measures of sexual orientation identify different (albeit overlapping) populations. Laumann et al. (1994) found that of the 8.6% of women reporting some same-gender sexuality, 88% reported same-gender sexual desire, 41% reported some same-gender sexual behavior, and 16% reported a lesbian or gay identity. Of 10.1% of men, reporting some same-gender sexuality, 75% reported same-gender sexual desire, 52% reported some same-gender sexual behavior, and 27% reported a gay identity.
In another study, Ross et al. (2003) showed that there was a discrepancy between self-reported sexual orientation identity and sexual behavior in a street outreach sample in Houston. In their study, which was focused on HIV/AIDS prevention, they concluded that it was critical to assess sexual behavior rather than identity in conducting research to inform HIV-risk interventions and clinical screening programs.
A third concern with the Kinsey Scale is that it inappropriately measures homosexuality and
heterosexuality on the same scale, making one the trade-off of the other. This concern arises out of research in the 1970s on masculinity and femininity which found that the concepts of
masculinity and femininity are more appropriately measured as independent concepts on
separate scales rather than as a single continuum with each one representing opposite extremes (Bem, 1981). Measured on the same scale masculinity and femininity acted as trade-offs in which to be more feminine one had to be less masculine or to be more masculine one had to be less feminine. Considered as separate dimensions one could be simultaneously very masculine and very feminine (androgynous) or not very much of either (undifferentiated). Similarly, considering homosexuality and heterosexuality on separate scales allows for one to be both very heterosexual and homosexual (bisexual) or not very much of either (asexual). Bullough (1990) echoed this concern with the Kinsey scale in the following statement: “I am, however, at this point in my research, convinced that the Kinsey scale has outlived its political usefulness and we need a more effective scholarly measuring tool. In fact, the Kinsey scale offers the same kind of difficulty that the traditional masculine-feminine scale did until it was realized that women could have masculine traits and still be feminine and vice versa.”
When homosexuality and heterosexuality are measured independently rather than as a
continuum, the degree of homosexuality and heterosexuality can be independently determined, rather than simply the balance between homosexuality and heterosexuality as determined using the Kinsey Scale. This idea was first put forth by Shively and DeCecco (1977) who proposed a five-point scale on which heterosexuality and homosexuality would be independently measured (see Shively). Using this scale they proposed the assessment of two dimensions of sexual orientation: physical and affectional preference.
Unfortunately, studies using or examining Shively and DeCecco's (1977) proposed measure of
sexual orientation could not be found in the published literature, however a study that briefly
examined this issue was found using a different scale. In this study, Storms (1980) measured the extent of sexual fantasies with the other sex on one scale and the extent of sexual fantasies with the same sex on another scale. He found that bisexuals in his sample were as likely to report homosexual fantasies as homosexuals were to report homosexual fantasies, and his bisexuals were as likely to report heterosexual fantasies as heterosexuals were to report heterosexual fantasies. He concluded, using the logic that bisexuals should be less likely to report homosexual fantasies than homosexuals, and less likely to report heterosexual fantasies than heterosexuals, that homosexuality and heterosexuality should be measured independently (at least in relationship to fantasies).
The Sell Assessment of Sexual Orientation was developed in light of the major concerns with
existing sexual orientation measures as discussed above (see Sell Assessment) (Gonsiorek, et al., 1995; Sell, 1996). That is, the Sell Assessment measures sexual orientation on a continuum, considers different dimensions of sexual orientation, and considers homosexuality and heterosexuality separately. The Sell Assessment contains 12 questions, 6 of which assess sexual attractions, 4 of which assess sexual behavior, and 2 of which assess sexual orientation identity. Of these, Sell considers the questions assessing sexual attractions to be the most important when the intent of the study is to measure sexual orientation, as he defines sexual orientation as the “extent of sexual attractions toward members of the other, same, both sexes, or neither.” Therefore, sexual attractions more closely reflect this conceptualization of sexual orientation than other attributes, such as sexual behavior or sexual orientation identity, and therefore are a better measure of sexual orientation.
Sexual behaviors and sexual orientation identity are measured in addition to sexual attractions in the Sell Assessment to provide supplemental information. Sexual behaviors are measured because they are often the result of sexual attractions and, therefore, provide a reflection of them. However, as a result of social and cultural influences, sexual attractions and behaviors will not always correspond. Sexual orientation identity is measured because it should also be closely linked to sexual attractions. That is, a person should/may identify as homosexual if attracted to the same sex, as heterosexual if attracted to the other sex, and bisexual if attracted to both sexes. Once again, however, as a result of social and cultural influences, sexual attractions and sexual orientation identity will not always correspond.
Questions concerning sexual attraction, sexual behavior, and sexual orientation identity will not be equally important in all studies and must be considered in the context of a study. For
example, a study examining the spread of HIV among homosexual men would want to measure sexual attractions to identify the total population of homosexuals and measure sexual behaviors to identify individuals most at risk for the spread of HIV. The same study may want to measure sexual orientation identity if the results will be used for prevention efforts. That is, individuals who identify as homosexual may be different from and easier to target with prevention efforts than homosexual men (identified as homosexual based upon reported sexual attractions and/or behaviors) who do not identify as homosexual.
Unmodified, the six pairs of questions and responses to the Sell Assessment provide a profile of a subject's sexual orientation. This is, however, more information than many researchers will find necessary for the assessment of a subject's sexual orientation. There are, therefore, four sets of “summaries” of the Sell Assessment that can be used to simplify data analysis. The biggest concern with the Sell Assessment is that its reliability and validity, like previous measures, remains largely unexamined (Gonsiorek, et al., 1995; Sell, 1996).
The Sell Assessment of Sexual Orientation is intended to provoke debate about the measurement of sexual orientations, and not necessarily provide a final solution to the question of how to best measure this construct. Researchers are encouraged to use it as a foundation of or beginning for the creation of better measures. One researcher who has attempted to do this is Friedman who is developing an adolescent measure of sexual orientation (see Friedman Measure) (Friedman et al., 2004).
CHOOSING A MEASURE OF SEXUAL ORIENTATION
Researchers are ever more frequently recognizing the need to include a sexual orientation variable in their research studies. Although problems assessing other demographic variables such as race and ethnicity have been examined and debated extensively in the literature, this process is only beginning for sexual orientation. With the review provided here, this chapter informs and hopefully advances this important process. However, definitive recommendations of one measure over another cannot legitimately be offered at this time. Rather, as with other recent reports, further research on the measurement of sexual orientation is recommended here (Solarz, 1999; Gay and Lesbian Medical Association, 2001).
Researchers wanting to measure sexual orientation today have a number of choices of
measurement tools. These include simple categorical measures like the one proposed by Miller (2002), the Kinsey Scale (Kinsey et al., 1948), the Klein Scale (Klein et al., 1985), the Shively and DeCecco Scale (Shively and DeCecco, 1977), The Sell Assessment (Sell, 1996) and the Friedman Measure of Adolescent Sexual Orientation (Friedman et al., 2004).(1) None of these is completely satisfactory. First, simple categorical scales are unsatisfactory for the reasons outlined by Kinsey but also because they have rarely had their validity and reliability thoroughly examined. Second, the Kinsey Scale is unsatisfactory because it forces the artificial combination of psychological and behavioral components and perhaps incorrectly requires individuals to make tradeoffs between homosexuality and heterosexuality. Third, the Klein scale is unsatisfactory because the relative importance of each dimension in measuring sexual orientation has not been thoroughly investigated or grounded in theory, and like Kinsey, Klein required subjects to make trade-offs between heterosexuality and homosexuality. Fourth, the Shively and DeCecco scale is unsatisfactory because its properties have not been thoroughly investigated and its consideration of physical and affectional preference may be oversimplified or even inappropriate. Finally, the Sell Assessment and Friedman Measure of Adolescent Sexual Orientation, while firmly grounded in current theoretical thinking about the measurement of sexual orientations, remain largely
untested and are perhaps too complicated and burdensome for average research requirements.
In reality, the majority of research studies that want to assess sexual orientations will only be able to add a single question to do so. The problems inherent in this approach should be particularly evident from this review. However, if one must be chosen, there are resources available to assist with making such choices. One such resources is the Recommend page on this website, which attempts to track all such measures and makes recommendations concerning them.
NOTES
(1) Other proposed scales that do not advance the field of sexual orientation measurement
theoretically, but are of some interest include: Sambrooks, J. E., MacCulloch, M. J. A modification of the sexual orientation method and automated technique for presentation and scoring. British Journal of Social and Clinical Psychology. 1973;12:163-174; Berkey B. R., Perelman-Hall T, Kurdek LA. The multidimensional scale of sexuality. Journal of Homosexuality. 1990;19(4):67-87.; Coleman E. Toward a synthetic understanding of sexual orientation. In HomosextialitylHeterosexality: Concepts of sexual orientation. New York: Oxford University Press, 1990.
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INTRODUCTION
Conceptually defining populations, such as those defined by race and ethnicity, and developing methods to operationally identify members of those populations, have continually challenged researchers (LaVeist, 2002). Today, as scientists begin to treat sexual orientation as a demographic variable like race and ethnicity, it is important to critically examine and clarify our conceptualizations of sexual orientation as well as critically examine measures used to operationally identifying the sexual orientation of research subjects.
There is much evidence that researchers are often confused as to what they are studying when
they assess sexual orientations in their research. Several literature reviews have found that
researchers' conceptual definitions of these populations are rarely included in reports of their
research and, when they are included, they often differ theoretically. Further, the methods used to measure sexual orientations in these studies do not always correspond with the most common conceptualizations of sexual orientation (Shively, et al. 1985; Sell and Petrulio, 1995; Chang and Katayama, 1996). Sell and Petrulio recommended that researchers work to develop uniform conceptual definitions of terms used to label sexual orientations and that uniform methods of operationally identifying sexual orientations be agreed upon for use in research studies. They believe it is imperative that researchers who claim to be studying these populations begin to clarify what it is they are actually studying and recognize more explicitly the effect their research methods have upon their findings. Sell and Petrulio’s recommendation’s echo the much earlier work of Henry who conducted one of the most detailed studies of homosexuality ever produced (Henry, 1941). Henry concluded that: “Unless the word homosexual is clearly defined, objective discussion regarding it is futile, and misunderstanding and erroneous conclusions are inevitable (Henry, 1955).”
To clear up some of this confusion, this chapter reviews and critiques conceptual definitions of sexual orientations and the measures used to identify and classify subjects' sexual orientations that have been proposed and used by scientists and laypersons since the 1860s in Europe and the United States. It was in the 1860s that the formal study of sexual orientations was founded by Ulrichs. It is hoped that this review will encourage researchers to be more critical of the methods they use to identify and label the sexual orientation of research subjects.
CONCEPTUAL DEFINITIONS OF SEXUAL ORIENTATION
Many different terms and definitions have been proposed over the last 140 years to describe the sexual orientation of study subjects. One of the earliest and most important sexual orientation classification schemes was proposed by Ulrichs in a series of pamphlets he privately published in the 1860s (Carpenter, 1908; Ulrichs, 1994). Ulrichs’ scheme, which was only intended to describe males, separated them into three basic categories: dionings, urnings, and uranodionings (see Karl Ulrichs). These terms were derived from a speech by Pausanias in Plato's Symposium in which Pausanias refers to Uranus (heaven) (Plato. The Symposium and The Phaedrus. State of New York Press, Albany, NY, 1993). Arguably these categories directly correspond with the categories used today: heterosexual, homosexual and bisexual (Cory, 1951). Homosexual women, who were largely ignored by early researchers, were referred to as urningins and heterosexual women were referred to as dioningins by Ulrichs (Bullough, 1990).
Mayne, a follower of Ulrichs, provided a definition of an urning in the first major work on
homosexuality to be written by an American. He defined an urning as “a human being that is
more or less perfectly, even distinctly, masculine in physique; often a virile type of fine
intellectual, oral and aesthetic sensibilities: but who, through an inborn or later-developed
preference feels sexual passion for the male human species. His sexual preference may quite
exclude any desire for the female sex: or may exist concurrently with that instinct (Mayne, 1908).” Mayne’s definition also encompasses male uranodionings by stating that desire for the female sex may exist concurrently.
In addition to his effect on Mayne, Ulrichs had a profound influence on the works of many early researchers including Westphal (1869), Symonds (1883, 1891), Krafft-Ebing (1886), Moll (1891), Carpenter (1894, 1908), Ellis and Symonds (1896), and Hirschfeld (1914). Further, through the works of these researchers, Ulrichs is credited with influencing Freud and Jung (Bullough, 1994). While they may differ significantly, the conceptualizations of sexual orientation most often cited today generally have their root in the works of Ulrichs.
Even the terms “homosexuality” and “heterosexuality,” which Ulrichs did not prefer, have direct links to him. The term homosexual is an inappropriate combination of Greek and Latin that disturbed many early researchers who wanted it replaced, but recognized that it was too deeply rooted in the literature by the time they arrived on the scene (Robinson, 1936; Kinsey et at, 1948). The term homosexual may have been introduced into English by Symonds in his first edition of A Problem of Modern Ethics in 1891 (Boswell, 1980). These terms homosexuality and heterosexuality first appeared in a letter to Ulrichs drafted on May 6, 1868, from Benkert, a German-Hungarian physician and writer (Ulrichs, 1994). Later, Benkert outlined his definition of homosexuality in a pamphlet published in 1869. His definition read:
In addition to the normal sexual urge in man and woman, Nature in her sovereign mood has endowed at birth certain male and female individuals with the homosexual urge, thus placing them in a sexual bondage which renders them physically and psychically incapable-even with the best intention-of normal erection. This urge creates in advance a direct horror of the opposite sexual (sic) and the victim of this passion finds it impossible to suppress the feeling which individuals of his own sex exercise upon him (cited in Robinson, 1936).
Today the terms heterosexual (straight), homosexual (gay and lesbian), and bisexual are the most commonly used terms by researchers to describe sexual orientations (Shively et al., 1985; Sell and Petrulio, 1995). While not many other terms have been proposed to describe heterosexuality or bisexuality, an overabundance of terms have been used by researchers to describe homosexuality, including uranianism, homogenic love, contrasexuality, homo-erotism, similsexualism, tribadism, sexual inversion, intersexuality, transexuality, third sex, and psychosexual hermaphroditism (Ulrichs, 1994; Moll, 1891; Carpenter, 1894, 1908; Ellis and Symonds, 1896; Mayne, 1908; Kinsey et al., 1948, 1953). Even today terms take on new meaning and importance for describing sexual orientations. The term queer for example is defined by Legman in 1941 as: “Homosexual; more often used of male homosexuals than of Lesbians. As an adjective it is the most common in use in America.” At the time Legman wrote, the term was slang and used pejoratively. Currently, the term still means “homosexual,” but is frequently used nonpejoratively in scholarly works (for example, see Signorile, 1993; Breit et al, 1994; Feinberg, 1994; Goldberg, 1994; Packard and Packard, 2005). Today's preferred terms and the term “sexual orientation” itself have a wide variety' of definitions in the literature but these generally comprise one or both of two components: a “psychological” component and a “behavioral” component. Not all definitions include both of these components, and as are discussed in detail below, definitions that include both components use either the conjunction “and” or “or” to join them.
Mayne's (1908) definition of the term Urning and Benkert's of the term homosexual (Robinson, 1936) only include a description of the psychological state. Mayne discussed how an individual's feelings of sexual passion determine their sexual orientation while Benkert talked of an “urge.” Ellis, one of the most important writers on sexuality in late 19th and early 20th century England, also only talked of a psychological entity which he described as “sexual instinct.” Ellis defined homosexuality as “sexual instinct turned by inborn constitutional abnormality toward persons of the same sex” (Ellis and Symonds, 1896). Ellis used the term “sexual inversion” at the time this definition was provided, but in later versions of his work substituted the term “homosexuality” (Ellis and Symonds, 1896; Ellis, 1942). Two of the earliest medical journal articles about homosexuality to appear in the English language provide a definition that, like the other early definitions, does not discuss sexual behavior. Their definition, which in both cases is a translation of Westphal's German definition describes homosexuals as persons that: “as a result of their inborn nature felt themselves drawn by sexual desire to male individuals exclusively” (Blumer, 1882; Shaw & Ferris, 1883).
These definitions and other early ones generally omit any discussion of behavior (and in
particular sexual behavior), except to say that the thought of it with the other sex is repulsive or horrifying to the homosexual. Another definition of this type was provided by Forel (1924) in his popular book The Sexual Question. Forel states “However shocking or absurd the aberrations of the sexual appetite and its irradiations may be, of which we have spoken hitherto, they are at any rate derived from originally normal intercourse with adults of the opposite sex. Those we have now to deal with are distinguished by the fact that not only the appetite itself, but all its psychic irradiations are directed to the same sex as the perverted individual, the latter being horrified at the idea of genital contact with the opposite sex, quite as much as a normal man is horrified at the idea of homosexual union.” Krafft-Ebing, like his contemporaries, even makes the point to exclude behavior front the diagnosis of homosexuality. Krafft-Ebing (1886) stated that “the determining factor here is the demonstration of perverse feelings for the same sex; not the proof of sexual acts with the same sex. These two phenomena must not be confounded with each other.”
More recent definitions often include both components. For example LeVay (1993) defined sexual orientation as “the direction of sexual feelings or behavior, toward individuals of the opposite sex (heterosexuality), the same sex (homosexuality), or some combination of the two (bisexuality),” and Weinrich (1994) defined homosexuality “either (1) as a genital act or (2) as a long-term sexuoerotic status.” Here the psychological states referred to are “sexual feelings” and “sexuoerotic status,” and the behavioral outcome is “sexual behavior” as referred to by LeVay and a “genital act” as referred to by Weinrich. The psychological and behavioral components in both definitions are joined by “or” signifying that either one can be used to assess sexual orientation.
In A Descriptive Dictionary and Atlas of Sexology (Francoeur et al, 1991), homosexuality is
broadly defined as “the occurrence or existence of sexual attraction, interest and genitally
intimate activity between an individual and other members of the same gender.” Here (the psychological components are “sexual attraction” and “interest” and the behavioral outcome is described as “genitally intimate activity.” Unlike the definitions of LeVay (1993) and Weinrich (1994), this definition joins the two components with the conjunction “and.” Using the conjunction “and” makes it unclear as to whether both components are necessary for the assignment of sexual orientation classifications.
At the other extreme from the early definitions provided by Mayne and Benkert are definitions that only include discussions of the behavioral component. For example, Stedman's Medical Dictionary (1982) defined homosexuality as “sexual behavior, including sexual congress, between individuals of the same sex, especially past puberty.” Here the psychological component does not seem to hold much if any importance for the assessment of sexual orientation. Beach (1950) is emphatic about only including sexual behavior in the definition of sexual orientation in his critique of the first English language translation of Gide's defense of homosexuality, Corydon. Beach (1950) states that “the term (homosexuality) means different things to different people . . . it is preferable to set forth the significance of the term as used in this discussion. Homosexuality refers exclusively to overt behavior between two individuals of the same sex. The behavior must be patently sexual, involving erotic arousal and, in most instances at least, resulting in the satisfaction of the sexual urge.” According to Diamond (1993), it is this type of definition that is favored by researchers determining the size of the “homosexual” population in various countries. In the studies reviewed by Diamond, while all used some assessment of sexual behavior to determine the prevalence of sexual orientations, none used any assessment of a psychological
state (such as sexual attraction).
Thus far I have discussed the two definitional components of sexual orientation as if the
components themselves were uniform across definitions, but as is evident in the examples
already provided, there are important variations. Psychological components of definitions may include the terms “sexual passion,” “sexual urge ... .. sexual feelings,” “sexual attraction,” “sexual interest,” “sexual arousal,” “sexual desire,” “affectional preference,” “sexual instinct,” “sexual orientation identity,” and “sexual preference.” “Sexual preference” has been used as a substitute for the term “sexual orientation,” but Gonsiorek and Weinrich (1991) believe it “is misleading as it assumes conscious or deliberate choice and may trivialize the depth of the psychological processes involved.” They therefore recommend the term sexual orientation because most research findings indicate that homosexual feelings are a basic part of an individual's psyche and are established much earlier than conscious choice would indicate.” Each of these terms may have a distinct meaning and not necessarily be indicative of the same phenomenon. That is, different terms in definitions may be describing slightly different phenomena despite the similar label for that phenomena.
Similarly, the behavioral component varies between definitions. Behavior can be stated simply as “sexual behavior” or it can be described, for example, as “genital activity,” “sexual intercourse,” “sexual contact,” or “sexual contact that achieves orgasm.” Each one of these presents further challenges for researchers. That is, how do we define each of these terms within the definition itself and how would we operationalize them for measurement?
Obviously definitions and preferred terms vary significantly from researcher to researcher and across time. While, it is not possible from this review to say one definition or set of terms is “better” than another, it is possible to make a few modest recommendations. First, all researchers who intend to collect sexual orientation data should dedicate time to choosing one of the definitions described here or developing their own definition before they begin their research. And second, researchers should make the terms and definitions they are using explicit when discussing research studies and findings. In the next section the operational measurement of sexual orientation is reviewed.
MEASURES OF SEXUAL ORIENTATION
As was demonstrated above, conceptualizations of sexual orientation vary dramatically between researchers. Measures of sexual orientation, as will be shown below, vary widely as well. However, this variation, like the variation in definitions, provides important insight to modern researchers.
Some of the earliest reports of assessing sexual orientation are found in the documents of the
Western Church, which encouraged individuals to confess their sins. In particular, religious
documents show the Church's concern with asking sensitive questions about such topics as
sodomy. These documents instructed priests in the 1500s “not to show amazement; exhibit a
contorted face; show revulsion (no matter what enormities are confessed) rebuke the penitent; or exclaim ‘Oh, what vile sins!’” when discussing sensitive subjects (Lee, 1993; Tentler, 1977).
De Pareja, who went to Florida as a missionary to the Timucua Indians in 1595, outlined specific questions to identify Sodomites in his book, Confessionario (Katz, 1992). These questions included:
1. Have you had intercourse with another man?
2. Or have you gone around trying out or making fun in order to do that? (Katz, 1992).
Pareja further provided questions to be asked of boys who may have committed sodomy including the following:
3. Has someone been investigating you from behind?
4. Did you consummate the act? (Katz, 1992).
Several centuries later, Ulrichs, in his series of pamphlets in the 1860s, outlined a set of
questions that could be asked to determine if a man was an Urning (Ulrichs, 1994). These
questions included:
1. Does he feel for males and only for males a passionate yearning of love, be it gushing and
gentle, or fiery and sensual?
2. Does he feel horror at sexual contact with women? This horror may not always be found but when it is found, it is decisive.
3. Does he experience a beneficial magnetic current when making contact with a male body in its prime?
4. Does the excitement of attraction find its apex in the male sexual organs?
Mayne (1908) also outlined a series of several hundred questions for the personal diagnosis of Urnings and Urningins. These questions include:
1. At what age did your sexual desire show itself distinctly?
2. Did it direct itself at first most to the male or to the female sex? Or did it hesitate awhile
between both?
3. Is the instinct unvaryingly toward the male or female sex now? Or do you take pleasure (or
would you experience it) with now a man, now a woman?
4. Do you give way to it rather mentally or physically? Or are both in equal measure?
5. Is the similsexual desire constant, periodic or irregularly felt?
6. In dreams, do you have visions of sexual relations with men or women, the more frequently and ardently?
The respondents to Pareja's, Ulrichs', and Mayne's questions were expected to be able to provide a yes or no answer. That is, the person was either categorized as a “Sodomite,” “Urning,” or “Urningin,” or not. This simple categorical scheme for the classification of sexual orientations remains the dominant one used by researchers today. That is, subjects are classified as homosexual or heterosexual based upon their sexual orientation identity or sexual behavior (Sell and Petrulio, 1995). In major health surveys, the state of the art question to assess sexual orientations, when only one question can be asked, is (Miller, 2002):
Which of the following best describes how you think of yourself? 1) Straight or Heterosexual, 2) Gay or Lesbian, 3) Bisexual, 4) Don’t know/Not Sure.
Despite this focus on single question measures, more sophisticated measures of sexual
orientation have been proposed over the last 50 years as researchers have encountered or
discovered the limitations of simple categorical measures. The most important of these
measures are reviewed below.
The most influential scale to be proposed during these years was put forth by Kinsey et al. 1948, 1953 in their reports on sexual behavior in the human male and female. Kinsey et al. proposed a bipolar scale that allowed for a continuum between “exclusive heterosexuality” and “exclusive homosexuality (see Kinsey Scale).” Kinsey et al. provided the following important justifications for their decision to depart from the dichotomous measures of his predecessors:
The world is not to be divided into sheep and goats. Not all things are black nor all things white. It is a fundamental of taxonomy that nature rarely deals with discrete categories. Only the human mind invents categories and tries to force facts into separated pigeon-holes. The living world is a continuum in each and every one of its aspects. The sooner we learn this concerning human sexual behavior the sooner we shall reach a sound understanding of the realities of sex (Kinsey et al., 1948).
It is characteristic of the human mind that it tries to dichotomize in its classification of phenomena. Things are either so, or they are not so. Sexual behavior is either normal or abnormal, socially acceptable or unacceptable, heterosexual or homosexual; and many persons do not want to believe that there are gradations in these matters from one to the other extreme (Kinsey et al., 1953).
One of the more striking facts about these statements is that Kinsey had been trained as a
taxonomist (Weinrich, 1990). It had been much of his life work to develop such dichotomous, yes or no, classifications as he so easily dismissed here. But by dismissing dichotomous
classifications and developing a bipolar continuous model, a new way of measuring sexual
orientation, providing a new perspective on sexuality, was created. However, as it forces subjects into one of seven categories, the Kinsey Scale is not a true continuum. This is fortunate in some ways because the seven points are difficult to assign and if there were an infinite number of points the task would be that much more difficult.
Masters and Johnson (1979), in a major study of homosexuality, provide the following discussion about the difficulty of assigning Kinsey ratings:
There was also concern in arbitrarily selecting the specific classification of Kinsey grades 2 through 4 for any individual who had had a large number of both homosexual and heterosexual experiences. The ratings were assigned by the research team after detailed history-taking, but it is difficult for any individual to be fully objective in assessing the amount of his or her heterosexual versus homosexual experience when there has been a considerable amount of both types of interaction. Some of these preferences ratings might well be subject to different interpretation by other health-care professionals.
Masters and Johnson further state that:
Kinsey 3 classification was the most difficult to assign of the ratings. Relative equality in any form of diverse physical activity is hard to establish. Particularly was this so when the interviewer, in attempting to separate mature sexual experience into its homosexual and heterosexual components, was faced with a history of a multiplicity of partners of either sex. The problem was augmented by the subjects' frequently vague recall of the average number of sexual interactions with each partner.
It is evident from these reports that it is difficult to determine the relative importance of the
heterosexual and homosexual in a person's history when using the Kinsey Scale, but this is only one of several concerns often expressed by researchers about this scale. A second concern with the Kinsey Scale is that it lumps individuals who are significantly different based upon different aspects or dimensions of sexuality into the same categories (Weinrich et al., 1993; Weinberg et al., 1994). In fact, Kinsey himself took two dimensions of sexual orientation, “overt sexual experience” and “psychosexual reactions,” into account when applying his scale. Kinsey el al. (1948) provides the following discussion of these two dimensions and how they were used in the assessment of sexual orientation:
It will be observed that the rating which an individual receives has a dual basis. It takes into account his overt sexual experience and/or his psychosexual reactions. In the majority of instances the two aspects of the history parallel but sometimes they are not in accord. In the latter case, the rating of an individual must be based upon an evaluation of the relative importance of the overt and the psychic in his history (Kinsey et al., 1948).
It can be argued that valuable information was lost by collapsing these two separate values into one final score. A common solution that avoids the loss of information is to assess dimensions of sexual orientation separately and report the scores independently as Kinsey could have easily done. When this approach is taken, the two most commonly assessed aspects of sexual orientation are sexual behavior and sexual fantasies. These two dimensions are most likely chosen because they correspond with the two dimensions, “overt sexual experience” and “psychosexual reaction” proposed by Kinsey (Kinsey 1948; Sell and Petrulio 1995). They may also be chosen because they reflect the behavioral and psychological components of definitions as discussed in the previous section. But sexual behavior and sexual fantasies are not the only dimensions that may be considered. For example, Klein et al. (1985) proposed in the Klein Sexual Orientation Grid (KSOG) the assessment of seven dimensions including sexual attraction, sexual behavior, sexual fantasies, emotional preference, social preference, self identification and heterosexual/homosexual life-style (see Klein Grid). A concern with assessing multiple dimensions is that as each is added the overall scale becomes more burdensome and less practical for many research purposes. Researchers therefore tend to limit the number of assessed dimensions.
Diamond (1993) reviewed several research studies in which sexual behavior and sexual fantasies were assessed on the Kinsey Scale. He reported that this is somewhat common in studies of specific gay populations. In the studies reviewed, there appears to be a high but not perfect correlation between reported sexual behavior and fantasy. The value of measuring these two dimensions for the assessment of sexual orientation or any other dimension has not been well determined (Ross et al., 2003).
Only a few published studies have explicitly examined the value of studying more than one
dimension of sexual orientation. Weinrich et al. (1993) found, using factor analysis, that all of the dimensions of sexual orientation proposed by Klein in the KSOG seem to be measuring the same construct. That is, all of the dimensions load on a first factor which accounts for most of the variance. However, they further find in the two samples that were studied that a second factor emerged containing time dimensions of social and emotional preferences, suggesting that the social and emotional preference dimensions may have also been mmeasuring something other than sexual orientation.
Another study, The National Health and Social Life Survey, demonstrated that sexual attraction, sexual behavior and sexual orientation identity measures of sexual orientation identify different (albeit overlapping) populations. Laumann et al. (1994) found that of the 8.6% of women reporting some same-gender sexuality, 88% reported same-gender sexual desire, 41% reported some same-gender sexual behavior, and 16% reported a lesbian or gay identity. Of 10.1% of men, reporting some same-gender sexuality, 75% reported same-gender sexual desire, 52% reported some same-gender sexual behavior, and 27% reported a gay identity.
In another study, Ross et al. (2003) showed that there was a discrepancy between self-reported sexual orientation identity and sexual behavior in a street outreach sample in Houston. In their study, which was focused on HIV/AIDS prevention, they concluded that it was critical to assess sexual behavior rather than identity in conducting research to inform HIV-risk interventions and clinical screening programs.
A third concern with the Kinsey Scale is that it inappropriately measures homosexuality and
heterosexuality on the same scale, making one the trade-off of the other. This concern arises out of research in the 1970s on masculinity and femininity which found that the concepts of
masculinity and femininity are more appropriately measured as independent concepts on
separate scales rather than as a single continuum with each one representing opposite extremes (Bem, 1981). Measured on the same scale masculinity and femininity acted as trade-offs in which to be more feminine one had to be less masculine or to be more masculine one had to be less feminine. Considered as separate dimensions one could be simultaneously very masculine and very feminine (androgynous) or not very much of either (undifferentiated). Similarly, considering homosexuality and heterosexuality on separate scales allows for one to be both very heterosexual and homosexual (bisexual) or not very much of either (asexual). Bullough (1990) echoed this concern with the Kinsey scale in the following statement: “I am, however, at this point in my research, convinced that the Kinsey scale has outlived its political usefulness and we need a more effective scholarly measuring tool. In fact, the Kinsey scale offers the same kind of difficulty that the traditional masculine-feminine scale did until it was realized that women could have masculine traits and still be feminine and vice versa.”
When homosexuality and heterosexuality are measured independently rather than as a
continuum, the degree of homosexuality and heterosexuality can be independently determined, rather than simply the balance between homosexuality and heterosexuality as determined using the Kinsey Scale. This idea was first put forth by Shively and DeCecco (1977) who proposed a five-point scale on which heterosexuality and homosexuality would be independently measured (see Shively). Using this scale they proposed the assessment of two dimensions of sexual orientation: physical and affectional preference.
Unfortunately, studies using or examining Shively and DeCecco's (1977) proposed measure of
sexual orientation could not be found in the published literature, however a study that briefly
examined this issue was found using a different scale. In this study, Storms (1980) measured the extent of sexual fantasies with the other sex on one scale and the extent of sexual fantasies with the same sex on another scale. He found that bisexuals in his sample were as likely to report homosexual fantasies as homosexuals were to report homosexual fantasies, and his bisexuals were as likely to report heterosexual fantasies as heterosexuals were to report heterosexual fantasies. He concluded, using the logic that bisexuals should be less likely to report homosexual fantasies than homosexuals, and less likely to report heterosexual fantasies than heterosexuals, that homosexuality and heterosexuality should be measured independently (at least in relationship to fantasies).
The Sell Assessment of Sexual Orientation was developed in light of the major concerns with
existing sexual orientation measures as discussed above (see Sell Assessment) (Gonsiorek, et al., 1995; Sell, 1996). That is, the Sell Assessment measures sexual orientation on a continuum, considers different dimensions of sexual orientation, and considers homosexuality and heterosexuality separately. The Sell Assessment contains 12 questions, 6 of which assess sexual attractions, 4 of which assess sexual behavior, and 2 of which assess sexual orientation identity. Of these, Sell considers the questions assessing sexual attractions to be the most important when the intent of the study is to measure sexual orientation, as he defines sexual orientation as the “extent of sexual attractions toward members of the other, same, both sexes, or neither.” Therefore, sexual attractions more closely reflect this conceptualization of sexual orientation than other attributes, such as sexual behavior or sexual orientation identity, and therefore are a better measure of sexual orientation.
Sexual behaviors and sexual orientation identity are measured in addition to sexual attractions in the Sell Assessment to provide supplemental information. Sexual behaviors are measured because they are often the result of sexual attractions and, therefore, provide a reflection of them. However, as a result of social and cultural influences, sexual attractions and behaviors will not always correspond. Sexual orientation identity is measured because it should also be closely linked to sexual attractions. That is, a person should/may identify as homosexual if attracted to the same sex, as heterosexual if attracted to the other sex, and bisexual if attracted to both sexes. Once again, however, as a result of social and cultural influences, sexual attractions and sexual orientation identity will not always correspond.
Questions concerning sexual attraction, sexual behavior, and sexual orientation identity will not be equally important in all studies and must be considered in the context of a study. For
example, a study examining the spread of HIV among homosexual men would want to measure sexual attractions to identify the total population of homosexuals and measure sexual behaviors to identify individuals most at risk for the spread of HIV. The same study may want to measure sexual orientation identity if the results will be used for prevention efforts. That is, individuals who identify as homosexual may be different from and easier to target with prevention efforts than homosexual men (identified as homosexual based upon reported sexual attractions and/or behaviors) who do not identify as homosexual.
Unmodified, the six pairs of questions and responses to the Sell Assessment provide a profile of a subject's sexual orientation. This is, however, more information than many researchers will find necessary for the assessment of a subject's sexual orientation. There are, therefore, four sets of “summaries” of the Sell Assessment that can be used to simplify data analysis. The biggest concern with the Sell Assessment is that its reliability and validity, like previous measures, remains largely unexamined (Gonsiorek, et al., 1995; Sell, 1996).
The Sell Assessment of Sexual Orientation is intended to provoke debate about the measurement of sexual orientations, and not necessarily provide a final solution to the question of how to best measure this construct. Researchers are encouraged to use it as a foundation of or beginning for the creation of better measures. One researcher who has attempted to do this is Friedman who is developing an adolescent measure of sexual orientation (see Friedman Measure) (Friedman et al., 2004).
CHOOSING A MEASURE OF SEXUAL ORIENTATION
Researchers are ever more frequently recognizing the need to include a sexual orientation variable in their research studies. Although problems assessing other demographic variables such as race and ethnicity have been examined and debated extensively in the literature, this process is only beginning for sexual orientation. With the review provided here, this chapter informs and hopefully advances this important process. However, definitive recommendations of one measure over another cannot legitimately be offered at this time. Rather, as with other recent reports, further research on the measurement of sexual orientation is recommended here (Solarz, 1999; Gay and Lesbian Medical Association, 2001).
Researchers wanting to measure sexual orientation today have a number of choices of
measurement tools. These include simple categorical measures like the one proposed by Miller (2002), the Kinsey Scale (Kinsey et al., 1948), the Klein Scale (Klein et al., 1985), the Shively and DeCecco Scale (Shively and DeCecco, 1977), The Sell Assessment (Sell, 1996) and the Friedman Measure of Adolescent Sexual Orientation (Friedman et al., 2004).(1) None of these is completely satisfactory. First, simple categorical scales are unsatisfactory for the reasons outlined by Kinsey but also because they have rarely had their validity and reliability thoroughly examined. Second, the Kinsey Scale is unsatisfactory because it forces the artificial combination of psychological and behavioral components and perhaps incorrectly requires individuals to make tradeoffs between homosexuality and heterosexuality. Third, the Klein scale is unsatisfactory because the relative importance of each dimension in measuring sexual orientation has not been thoroughly investigated or grounded in theory, and like Kinsey, Klein required subjects to make trade-offs between heterosexuality and homosexuality. Fourth, the Shively and DeCecco scale is unsatisfactory because its properties have not been thoroughly investigated and its consideration of physical and affectional preference may be oversimplified or even inappropriate. Finally, the Sell Assessment and Friedman Measure of Adolescent Sexual Orientation, while firmly grounded in current theoretical thinking about the measurement of sexual orientations, remain largely
untested and are perhaps too complicated and burdensome for average research requirements.
In reality, the majority of research studies that want to assess sexual orientations will only be able to add a single question to do so. The problems inherent in this approach should be particularly evident from this review. However, if one must be chosen, there are resources available to assist with making such choices. One such resources is the Recommend page on this website, which attempts to track all such measures and makes recommendations concerning them.
NOTES
(1) Other proposed scales that do not advance the field of sexual orientation measurement
theoretically, but are of some interest include: Sambrooks, J. E., MacCulloch, M. J. A modification of the sexual orientation method and automated technique for presentation and scoring. British Journal of Social and Clinical Psychology. 1973;12:163-174; Berkey B. R., Perelman-Hall T, Kurdek LA. The multidimensional scale of sexuality. Journal of Homosexuality. 1990;19(4):67-87.; Coleman E. Toward a synthetic understanding of sexual orientation. In HomosextialitylHeterosexality: Concepts of sexual orientation. New York: Oxford University Press, 1990.
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