Our review of recent prevalence estimates for the sexual dysfunctions is largely consistent with that reported 10 years ago by Spector and Carey (1990)
. Community samples indicate a current prevalence of 0-3% for male orgasmic disorder, 0-5% for erectile disorder, and 0-3% for male hypoactive sexual desire disorder (HSDD). Pooling current and 1-year figures provides community prevalence estimates of 7-10% for female orgasmic disorder, and 4-5% for premature ejaculation. For the point of comparison, Spector and Carey (1990)
reported a current prevalence of 4-10% for male orgasmic disorder, 4-9% for male erectile disorder, 5-10% for female orgasmic disorder, and 36-38% for premature ejaculation. Thus, only the prevalence of premature ejaculation is markedly different. The high estimate for premature ejaculation reported by Spector and Carey (1990)
was based upon two relatively small samples. The much lower estimate obtained in this review is based upon four studies with a total of over 2000 men and is thus more representative of the general population. The current review was able to provide an estimate of the prevalence of male HSDD, a figure unavailable previously. Stable community estimates of other sexual dysfunctions remain uncertain.
Spector and Carey (1990)
made four suggestions for new research in this area. Specifically, they called for increased use of (1) stratified samples representative of the general population; (2) psychometrically sound assessment techniques to facilitate interpretation and replication; (3) a common classification system to aid comparison across studies; and (4) collection of incidence data. There are some notable studies over the past ten years that have incorporated these methodological recommendations. For example, Ernst et al. (1993)
and Rekers et al. (1992)
used stronger sampling techniques, stratifying by psychological distress and age, respectively. The field has also had the benefit of several larger scale (> 1000 participants) random population surveys (e.g., Barlow et al., 1997
; Fugl-Meyer & Sjogren Fugl-Meyer, 1999
; Laumann et al., 1999
; Ventegodt, 1998
There has also been progress in assessment techniques. For example, Brown et al. (1990)
and Goggin et al. (1998)
use a modified version of the Structured Clinical Interview for DSM-III-R
(Brown & Rundell, 1993
). Reports of inter-rater reliability in several studies provide a measure of reliability of diagnoses (Brown & Rundell, 1990
; Meyer-Bahlburg et al., 1993
). Additional assessment instruments with known psychometric characteristics are also being used (e.g., the DISS-IIIA
was used by Robins, 1986; Chandraiah et al., 1991
; Lindal & Stefansson, 1993
, and Meyer-Bahlburg et al., 1993
; the GRISS
was used by Rust & Golombok, 1986
and Goldmeier et al., 1997
). Review of the studies in which the most psychometrically sound assessment techniques were used also demonstrates a trend toward using the DSM
as a common classification system.
Incidence data continues to be sparse. Wei et al. (1994)
is one exception. These authors report incidence data on erectile dysfunction stratified by age.
There have been a small number of excellent studies that have incorporated many important methodological features into study design (e.g., Fugl-Meyer & Sjogren Fugl-Meyer, 1999
; Lindal et al., 1993
). However, despite the increased attention in the past decade to the study of sexual dysfunctions there appears to have been relatively little methodological improvement overall. We identify three successive strategies for improvement in relation to assessment criteria. First, the criteria for determining a dysfunction need to be clearly reported. Although several investigators have used operational definitions, many studies failed to report the criteria they used in the paper. Lack of consistent reporting of assessment criteria make comparisons across studies difficult and hinder the accumulation of data across studies to enhance knowledge. Second, standard criteria for the sexual dysfunctions need to be adopted. The use of standard diagnostic criteria appears to be the exception rather than the rule among the studies reviewed. The DSM
and the multiaxial system proposed by Schover et al. (1982)
provide two potential options.
The third avenue for development is to examine sexual disorders
rather than simply the dysfunction
. The omission of psychological sequelae of the sexual dysfunctions is a significant methodological concern. According to the DSM-IV
), sexual disorder diagnoses need to be based on three criteria: (A) sexual dysfunction (i.e., physical / psychological manifestation (e.g., lack of orgasm, lack of erection, pain during intercourse, lack of sexual interest, etc.)), (B) the disturbance causes marked distress or interpersonal difficulty, and (C) the dysfunction is not better accounted for by another Axis I disorder (except another sexual dysfunction) and is not due to the physiological effects of a substance or general medical condition. Criteria A has frequently been incorporated into most investigators’ operational definitions. However, criteria B and C are typically omitted from the diagnostic criteria. From a clinical standpoint, the report of accompanying distress and/or interpersonal difficulty is important. However, this criterion was rarely addressed in the reported criteria in the studies reviewed. Typically, only the prevalence of symptoms
is reported although some exceptions can be noted. For example, Amr, Halim, and Moussa (1997)
report the prevalence of both erectile disorder determined by DSM-III-R
criteria as well as prevalence of erectile dysfunction symptoms. The latter led to a prevalence rate of 27% whereas the former resulted in a much lower (5%) rate. This additional level of detail provides especially helpful information regarding the underlying development of the disorder. For example, Amr et al. (1997)
reported significant increases in erectile dysfunction symptoms but not erectile disorder in relation to pesticide exposure. Such findings may be informative in understanding the biological and psychological contributions to the development of sexual disorders.
The study by Fugl-Meyer and Sjogren Fugl-Meyer (1999)
is particularly informative in respect to the relations between sexual dysfunction and sexual disorder characterized by resultant perceived psychosocial problems. This study assessed the prevalence of the dysfunctions as well as the percentage of participants who perceived their sexual dysfunction as problematic. For some dysfunctions, there was a high concordance between the presence of a dysfunction and perceived problems. For example, sixty-nine percent of the men reporting erectile dysfunction reported that it was problematic. In contrast, only forty-five percent of women with orgasmic dysfunction perceived it as problematic. Thus, in this study, if one defined female orgasmic disorder as the inability to attain orgasm the 1-year prevalence rate is 22%. In contrast, the prevalence rate is only 10% if one defines the disorder as the presence of the dysfunction and
the dysfunction causing a problem (marked distress or interpersonal difficulty in DSM-IV
terminology). This study clearly differentiates between sexual functioning on the one hand and a psychological disorder defined in part by subjective distress and disturbance in interpersonal relations. This study provides a clear demonstration of how differences in diagnostic criteria can have profound a effect on prevalence estimates. Such differences contribute to the wide discrepancies seen across some studies.
We acknowledge that most studies were designed only to obtain data on the occurrence of a symptom and that investigators did not claim to be assessing a disorder defined in the DSM
. Determination of the appropriateness of assessing a sexual dysfunction versus a disorder (in the DSM
sense) rests upon the goals of the study. Assessing solely the dysfunction is appropriate if the potential accompanying distress or interpersonal conflict is not
of interest. In some cases, the symptom is an important focal point as in the relationship between erectile dysfunction and health problems such as diabetes mellitus (Weinhardt & Carey, 1996
). In such studies, biological precursors are of interest. In more clinically focused research, determination of whether or not the dysfunction is accompanied by significant distress or interpersonal conflict is relevant. It is such psychosocial problems that are the impetus for intervention not variation in sexual functioning per se. For symptoms such as reduced sex drive, the importance of the symptom in isolation from DSM
criteria B or C is unknown, and the prevalence estimates are less useful.
The wealth of studies conducted over the past ten years is encouraging as are the adoption of the methodological suggestions that were outlined in Spector and Carey (1990)
. We note above some of the studies that have particularly sound methodological designs. These studies are exemplars that could guide the continuing development in the study of sexual functioning. These exemplars are unfortunately few in comparison to the full collection of studies. Many continue to have methodological problems that limit their potential usefulness. With continued attention to statistical design, it is hoped that methodologically rigorous studies will no longer be the exception to the rule.