• Erectile Dysfunction;
  • Prevalence;
  • Sociodemographic Factors;
  • Population-Based Study;
  • IIEF-5


  1. Top of page
  3. Introduction
  4. Method
  5. Results
  6. Discussion
  7. Conclusions
  8. Statement of Authorship
  9. References

Introduction.  This is a report of a population-based cross-sectional observational study in Western Australia (WA) on male erectile dysfunction (ED).

Aim.  To assess the prevalence of ED in WA and to examine its associated sociodemographic factors.

Method.  Postal questionnaires were sent to randomly selected age-stratified male population samples obtained from the WA Electoral Roll.

Main Outcome Measures.  In addition to items covering sociodemographic and clinical information, the Australian Standard Classification of Occupations (ASCO), the Socioeconomic Index for Area (SEIFA), and the 5-item International Index of Erectile Function (IIEF-5) were used.

Results.  One thousand seven hundred seventy (41.9%) of 4,228 questionnaires were returned. One thousand five hundred eighty (89.3%) were completed questionnaires from men aged 20.1 to 99.6 years (mean 57.9, median 59.1, standard deviation 18.5). The prevalences of any ED and of severe ED among adult males in WA, adjusted for age distribution, were 25.1 and 8.5%, respectively. Standardized to World Health Organization (WHO) World Standard Population, the corresponding prevalences were 23.4 and 7.4%. Prevalence, as well as severity, of ED increased with age. Thirty-eight percent of the participants who were married or had partners experienced ED (severe ED 19.1%). The prevalence of ED was not significantly different between “white-collar” and “blue-collar” workers. Despite the great majority of the affected participants having experienced ED for >1 year, only 14.1% reported having ever received any treatment for ED.

Conclusions.  The study has provided population-based epidemiological data on ED in Western Australian men covering a wide range of ages. The finding that ED is age related, highly prevalent, and grossly underdiagnosed and undertreated is pertinent to global population aging and a rapidly aging Australian population. To facilitate comparisons across populations with different age distributions, all future population-based studies on ED should be standardized to WHO World Standard Population. Chew K-K, Stuckey B, Bremner A, Earle C, and Jamrozik K. Male Erectile Dysfunction: Its Prevalence in Western Australia and Associated Sociodemographic Factors. J Sex Med 2008;5:60–69.


  1. Top of page
  3. Introduction
  4. Method
  5. Results
  6. Discussion
  7. Conclusions
  8. Statement of Authorship
  9. References

Erectile dysfunction (ED) refers to the consistent or recurrent inability to achieve and/or maintain a penile erection sufficient for satisfactory sexual performance [1,2].

Of late, there has been a plethora of population-based epidemiological studies on ED published in the medical literature. However, in addition to wide variations in the sociodemographic and clinical profiles of the study populations concerned, the findings from these studies vary considerablybecause of major methodological differences and deficiencies in study design [3]. Their results, therefore, can neither be used for general application nor for comparison between studies. [3]

Our previous study had provided epidemiological data on ED among adult male general medical practice attendees in Perth, Western Australia (WA) [4]. The current report on ED is based on a population-based, cross-sectional, observational study, the Western Australia Men's Health Study (WAMHS), conducted between October 2001 and December 2002.


  1. Top of page
  3. Introduction
  4. Method
  5. Results
  6. Discussion
  7. Conclusions
  8. Statement of Authorship
  9. References

Study Population

We set out to conduct a survey on ED and its correlates by postal questionnaire sent to representative samples of men in WA, which were stratified by their residence in and outside metropolitan Perth according to postcodes. The WA Electoral Roll for June 2001, which contains the demographic details of all adult Australian citizens residing in WA as their enrollment to vote is compulsory, provided the source for the representative samples.

With the assistance of the WA Department of Health, we generated 14 random samples, each consisting of 302 male residents, in strata defined by residence in and outside metropolitan Perth according to postcodes and seven decades of age from 20–29 to 80+ years. As most Western Australians reside in metropolitan Perth, oversampling of the areas outside metropolitan Perth was undertaken to ensure their proportionate representation.

The sample size was designed to give the study a power of 80% for detecting at 5% statistical significance the difference in prevalence of ED between the WAMHS and our previous study in general medical practice [4], allowing for a nonresponse fraction of 30%.

Study Questionnaire and Investigative Instruments

A total of 4,228 reply-paid study questionnaires were posted. The study questionnaire included items covering sociodemographic information, medical history and treatment, and sexual behavior and function.

The participants' main occupations in life were categorized according to the Australian Standard Classification of Occupations (ASCO) [5]. To reduce complexity, the number of occupational groups in ASCO was reduced from nine to six by merging those with similar job descriptions, regardless of the level of skill or specialization. According to the type of work involved in their occupations, the participants were also categorized as “white-collar” or “blue-collar” workers.

The Socioeconomic Index for Area (SEIFA), a measure of the socioeconomic conditions of each participant's residential postcode, has been derived by the Australian Bureau of Statistics (ABS) from population census data to provide an overview of a number of related variables associated with socioeconomic disadvantage [6]. We used four categories of SEIFA (SEIFA 1–4) in the WAMHS, with the lowest category SEIFA 1 indicating the greatest socioeconomic disadvantage.

We collected data on ED using the internationally validated 5-item International Index for Erectile Function (IIEF-5) [7], otherwise known as the Sexual Health Inventory for Man or SHIM. IIEF-5 scores of 22–25, out of the maximum of 25, suggest normal or adequate erectile function, and scores of <22 indicate ED. ED is then stratified into four levels of severity: 17–21 denoting mild ED, 12–16 mild to moderate ED, 8–11 moderate ED, and <8 severe ED.

Data Analyses

We examined the associations between ED and sociodemographic factors using Pearson's Chi-square tests. The t-tests and anova tests were used to compare mean ages. Using logistic regression models, we calculated odds ratios and 95% confidence intervals adjusted for age and the square of age. Analyses were performed with the Statistical Package for the Social Sciences (SPSS, SPSS Inc, Chicago, IL, USA) for Windows 12.0.

The prevalences of ED and the four levels of severity of ED were assessed for each age group in the WAMHS. The overall prevalences for the WAMHS were adjusted for age distribution of the male population in WA [8]. These overall prevalences were also standardized to World Health Organization (WHO) World Standard Population based on average world population between 2000 and 2025 [9].


  1. Top of page
  3. Introduction
  4. Method
  5. Results
  6. Discussion
  7. Conclusions
  8. Statement of Authorship
  9. References

Response and Participation

Of the 4,228 study questionnaires posted, 1,770 (41.9%) were returned, of which 1,580 (89.3%) were fully answered. Table 1 shows the age-specific response fractions.

Table 1.  Age distribution and response fractions of participants in Western Australia Men's Health Study (WAMHS) and age distributions of males in WA, males in Australia, and World Health Organization (WHO) World Standard Population
Age (years)WAMHSAge distribution (%)
Count%Response fractionMales in WAMales in AustraliaWHO World Standard Population

One hundred ninety one questionnaires were not completed. Only the ages were known in 186 of these men and 75.3% were aged 60 years and older (mean 70.8 years).

Of the participants with known WA postcodes, 742 (47.0%) were from metropolitan Perth.

Sociodemographic Characteristics of Participants

The 1,580 participants were aged from 20.1 to 99.6 years (mean 57.9, median 59.1, SD 18.5). The age distributions of the study population and of the male populations of WA and Australia are shown in Table 1, while Table 2 shows sociodemographic characteristics of the participants.

Table 2.  Sociodemographic characteristics of participants*
Sociodemographic factorsAge (years)
≥20 n = 1,58020–29 n = 12730–39 n = 18440–49 n = 22550–59 n = 24460–69 n = 25270–79 n = 265≥80 n = 217
  • *

    Expressed as % of study sample.

Marital status
 Married or with partner74.738.683.282.782.881.377.062.2
 Never been married8.458.313.
 Separated or divorced8.42.42.712.
Employment status
 In full- or part-time employment52.
 Retired (age)36.8000.42.048.484.288.0
 Retired (health reasons)6.802.23.19.415.57.96.1
Occupation (with adaptations)
 Managers and administrators17.87.112.514.718.417.921.128.1
 Professionals and associate  professionals25.125.227.725.333.223.421.523.5
 Tradespersons and related workers25.931.537.528.419.725.026.418.0
 Clerical sales and service workers9.
 Intermediate production and transport  workers and laborers16.118.114.721.314.815.515.112.0
Type of work
 “White-collar” work41.88.510.913.618.617.315.213.2
 “Blue-collar” work53.
 SEIFA 127.923.620.129.325.430.234.327.2
 SEIFA 226.821.327.227.628.323.027.530.4
 SEIFA 315.822.022.316.914.314.310.914.7
 SEIFA 421.324.423.419.623.819.820.820.3
Sexual activity
 Sexually active68.193.797.397.387.775.037.012.0
 Never been sexually active1.
 No longer sexually active27.
Sexual intercourse frequency
 Sexual intercourse regularly38.757.566.368.953.732.511.32.8
 Sexual intercourse sometimes14.722.016.817.818.014.712.82.8
 Sexual intercourse occasionally14.714.214.110.716.027.812.81.6.5
 Never had sexual intercourse1.
 No longer having sexual intercourse27.


The erectile function of the participants was stratified according to their IIEF-5 scores. IIEF-5 scores were not available for 154 (9.7%) participants. Of these 154 participants whose ages were known, 141 (84.4%) were aged 60 years and older (mean 73.3, median 77.7).

The prevalences of ED in the various age groups are shown in Table 3 and Figure 1. The prevalences of ED associated with sociodemographic factors and their age-adjusted odds ratios for ED are shown in Table 4.

Table 3.  Prevalence of erectile dysfunction (ED) in various age groups
Age group (years)Prevalence (%) of ED (IIEF-5 scores)
No ED 22–25ED <22Mild to severe EDNot known
  • *

    Adjusted for age distribution of WA male population.

  • Standardized to WHO World Standard Population.

20–29 (n = 127)81.915.710.
30–39 (n = 184)
40–49 (n = 225)84.912.
50–59 (n = 244)64.831.615.
60–69 (n = 252)39.352.422.29.92.817.58.3
70–79 (n = 265)17.469.410.
≥80 (n = 217)2.368.
WAMHS (n = 1,580)49.940.311.35.32.621.29.7
WA males (n = 675,000)25.1*11.0*3.6*2.0*8.5*
WHO Standard World Population23.411.

Figure 1. Age and prevalence of erectile dysfunction (ED).

Download figure to PowerPoint

Table 4.  Sociodemographic factors and erectile dysfunction (ED)
Sociodemographic factorsED <22Age-adjusted odds ratio for ED95% CI
 <50 years12.11.0 
 ≥50 years55.312.49.2–16.6
 ≥70 years68.945.931.0–67.9
Marital status
 Married / had partner38.01.0 
 Never been married27.86.53.4–12.7
 Separated / divorced53.42.61.6–4.1
Employment status
 In full- / part-time  employment20.41.0 
 Retired (age)–2.4
 Retired (health)–5.9
 Managers and  administrators41.81.0 
 Professional and  associate professionals37.01.10.7–1.7
 Tradespersons and  related workers38.01.50.9–2.3
 Clerical, sales, and  service workers47.01.40.8–2.5
 Intermediate production  and transport workers,  and laborers39.81.71.0–2.8
Type of work
 “White-collar” work39.41.0 
 “Blue-collar” work39.91.20.9–1.6
 SEIFA 339.01.40.9–2.2
 SEIFA 439.51.0 

The overall prevalence of ED among the 1,580 participants was 40.3% and 21.2% reported severe ED. Adjusted for age distribution of the male population in WA, the estimated prevalences of any ED and of severe ED in adult Western Australian men were 25.1 and 8.5%, respectively. On being standardized to WHO World Standard Population, the corresponding prevalences were 23.4% and 7.4%.

ED and Sociodemographic Factors


Both prevalence and severity of ED increased significantly with age, especially after the age of 50 years. Albeit mostly mild, ED was more prevalent (15.7%) among participants in the 20–29 years age group than in the 30–39 (8.7%) and 40–49 years (12.9%) age groups.

There was a decline in reported sexual activity in participants aged 60 years and older and a much sharper decline in those aged 70 years and older. However, a significant proportion of the elderly participants (42.6% of those aged ≥60 years and 25.7% of those aged ≥70 years) continued to be sexually active.

Marital Status

The majority (74.7%) of the participants were married or had partners, but only 72.9% of these participants were sexually active. Of those who reported being sexually active, 60.9% reported having sexual intercourse regularly.

Of the participants, 23.4% were widowers, had never been married, or were separated or divorced. Of these, 53.9% were sexually active and 39.2% of these sexually active men reported having sexual intercourse regularly. The age-adjusted odds for ED were higher among those who had never been married (OR = 6.5; 95% CI 3.4–12.7) or had been separated or divorced (OR = 2.6; 95% CI 1.6–4.1).

About 10% of the participants aged 70–79 years and about 30% of those aged 80 years and older were widowers.

Employment Status

Of the participants, 52.1% were in full- or part-time employment. One-third (32.9%) of the participants aged 60–69 years were still gainfully employed, as were 6.6% of those aged 70 years and older.

Of the participants, 36.8% were age retirees (mean age 75.9, median 75.6 years) and 6.8% had retired for health reasons (mean age 64.3, median 63.5 years). Relative to employed men, the age-adjusted odds for ED were significantly higher for men who had retired for health reasons (OR = 3.4; 95% CI 2.0–5.9).


Overall, 42.9% of the participants had “white-collar” jobs (managers, administrators, professionals, and associate professionals) and 51.6% were “blue-collar” workers (tradespersons, clerical, sales and service workers, production and transport workers, and laborers).

As an occupational group, clerical, sales, and service workers had the highest crude prevalence of ED, but, overall, “white-collar” and “blue-collar” workers had similar prevalence of and age-adjusted odds for ED.


Over half (54.7%) of participants were residents of areas of socioeconomic disadvantage (SEIFA 1 and 2).

The prevalence of ED was highest in SEIFA 1 (44.7%) and varied between 38.2 to 39.2% in SEIFA 2, 3, and 4. Compared with SEIFA 4, the age-adjusted odds for ED were not statistically different across the various categories of SEIFA (Table 4).

Duration and Treatment of ED

The duration of ED, reported by 468 (73.5%) of the 637 participants with ED, is shown in Table 5.

Table 5.  Duration and severity of erectile dysfunction (ED)
Duration of ED (years)Participants with EDIIEF-5 < 8 (%)Treated (%)
N%Cumulative (%)
  1. Number of participants with ED (IIEF-5 scores) = 637.

  2. Number of participants with ED who reported having or not having received treatment for ED = 597.

  3. Number of participants with ED who reported duration of ED = 468.


Most of the participants (89.1%) had experienced ED for more than 1 year, 74.8% for more than 2 years, and 12.2% for more than 10 years. ED was also more severe in participants with a longer duration of ED.

Of the 637 participants with ED, only 90 (14.1%) had ever sought and received treatment for ED.


  1. Top of page
  3. Introduction
  4. Method
  5. Results
  6. Discussion
  7. Conclusions
  8. Statement of Authorship
  9. References

The WAMHS is a population-based, cross-sectional observational study on ED of a representative sample of Western Australian males using the internationally validated IIEF-5.

Whereas most published studies on ED were conducted on men aged between 40 and 70 years, the ages of participants in the WAMHS ranged from 20.1 to 99.6 years. The findings are thus pertinent to the entire age spectrum of the adult male population in WA.

Although the study had been planned and was conducted prior to a critical review published in 2002 of population-based studies on ED [3], the WAMHS satisfies practically all the criteria proposed in that review for identifying studies of good quality.

The response of 41.9% (1,770 / 4,228) is comparable to the 44.7 and 47.6% achieved for studies in rural New York State in the United States (N = 5,198) [10] and in Brazil (N = 718) [11] respectively, although higher responses of 56.1 to 69.9% have been reported for studies in Germany (N = 8,000) [12], the Netherlands (N = 1,771) [13], and Finland (N = 2198) [14].

Full participation by 89.3% of respondents compares well with the range of 65.6% to 96.2% reported in other community-based studies [10,15–18].

Prevalence of ED

The prevalence of ED for the WAMHS was 40.3% and of severe ED 21.2%. The estimated prevalence of ED for men in WA aged 20 years and older, adjusted for age distribution of the WA male community, is 25.1% and of severe ED 8.5%.

Given the similarity of the age distributions between the adult male community of WA and of Australia (Table 1) [19,20], it is likely that these estimated prevalences are applicable nationwide.

The reporting of crude prevalences of ED for population samples with different age distribution has almost certainly resulted in the apparent significant differences in the prevalence of ED reported for different communities or countries. To avoid such artifacts, we have standardized our data to a nonvarying external reference and recommend routine application of this approach in order that the prevalences from this and other future studies of similar design may be meaningfully compared.

As in our previous study on ED in general medical practice in Perth, WA [4], the 20–29 years age group was found to have a higher prevalence of ED than the 30–39 years age group. Stresses related to early adulthood, budding relationships, and new responsibilities associated with entering the workforce and commencing independent living are possible contributory factors, although in a case report on “honeymoon impotence” among men aged 20–28 years, 26% were found to have vasculogenic ED [21]. It is difficult to exclude the possibility of bias in the data for the 20–29 years age group, as a combination of differential participation in the survey by affected individuals and the low response fraction among younger men may have inflated the apparent prevalence of ED among men aged 20–29 years. Few population-based studies have included men younger than 25 years of age [3]. It is of interest that in a study involving servicemen aged 25–55 years, the prevalence of ED, based on IIEF-5 scores, was also shown to be higher at 25% among younger men aged 25–28 years compared to 19 and 22% among men aged 29–34 years and 35–40 years, respectively [22].

Among the participants aged 40–69 years, the prevalences of ED and of severe ED were 33.0 and 8.6%, compared with the corresponding prevalences of 52.0 and 9.6% in the Massachusetts Male Aging Study (MMAS) [23], which employed a different investigative instrument and design.

In the population-based MARSH study using the single question on “the ability to get and keep an erection” as the investigative instrument, the prevalence of moderate or severe ED in men aged 40 years and older was estimated as 22.0% [24]. Based on their IIEF-5 scores, 32.1% of the 1,203 participants aged 40 years and older in our study had severe and moderate ED. The apparent difference is likely to be related to the fact that, compared to 13.3% in the MARSH study, 40.1% of these 1,203 participants were aged 70 years and older.

Age is the predominant factor in ED over and above all other sociodemographic factors. Consistent with the findings of the MMAS and other epidemiological studies on ED, the WAMHS confirms yet again that both the prevalence and the severity of ED increase with age. As 75.3% of the 186 men who did not participate in the study and 84.4% of the 141 participants whose IIEF-5 scores were unavailable were aged 60 years and older, the true prevalences of ED and of severe ED may have been higher than the observed figures of 25.1 and 8.5%.

Australian demography is changing rapidly in keeping with global population aging and the proportion of persons aged 65 years and older has been projected to increase dramatically [25]. As a highly prevalent and age-related condition, ED will no doubt pose huge clinical and socioeconomic challenges for providers of healthcare and social support services in the years ahead.

Sociodemographic Factors and ED

On the one hand, the majority of the participants in WAMHS were married or had partners, although more than a quarter of these men were not sexually active. On the other hand, of the participants who were widowers, had never been married, or were separated or divorced, well over 50% were sexually active, with 39.2% engaging in sexual intercourse regularly.

A sizeable minority of the participants aged 70 years and older also remained sexually active. Similarly, in the Global Study of Sexual Attitudes and Behaviors involving 13,618 male participants from 30 countries, 84% of men aged 40–80 years reported having had sexual intercourse within the 12 months preceding the study and 45% of those who were sexually active had sexual intercourse regularly [26]. Few epidemiological studies have reported on the sexual activity among their participants, particularly the elderly [27]. These findings will have implications in the planning and provision of facilities for the care of elderly men.

The age-adjusted odds ratio for ED among participants who had never been married relative to those who were married or had partners was significant at 6.5 (95% CI 3.4–12.7). This finding is consistent with the published observations that having never been married is significantly associated with an increased prevalence of ED [28] and that fewer married men have ED than nonmarried men [29].

The age-adjusted odds ratio for ED among those who were separated or divorced was also significantly high, suggesting that being separated or divorced may be a contributory factor to ED. However, it is just as possible that ED had contributed to separation and divorce in these men. Of note, it has been reported that men with severe ED are significantly more likely to be without regular sexual partners [30].

ED has previously been reported to be more prevalent in men with lower socioeconomic status [31]. In the WAMHS, ED was present in a smaller proportion of participants in full- or part-time employment than those who were unemployed, with the odds ratio for ED in the latter group attaining only borderline statistical significance.

Historically, classifying occupations has been a difficult process with problems of reliability and validity in cross-national comparisons. ASCO is a skill-based classification with similar conceptual framework as the International Standard Classification of Occupations developed by the International Labour Office [32]. Using ASCO with minor practical adaptations, meaningful international comparability with other similarly designed studies becomes possible.

Although as an occupational group clerical, sales and service workers had the highest crude prevalence of ED, there were no significant differences between the age-adjusted odds ratios for ED among the various occupational groups or between the “white-collar” and “blue-collar” workers. This contrasts with previous reports that a greater number of those employed in “blue-collar” occupations have ED and more severe ED than those in “white-collar” occupations [33,34].

SEIFA helps identify areas of socioeconomic disadvantage, but does not necessarily reflect the socioeconomic status of the individuals. It has, therefore, greater practical implications in the planning and delivery of healthcare services and potentially in the commercial marketing of products related to ED.

Of the 468 participants whose duration of ED was known, 224 (47.9%) had the affliction for 1–5 years. In a study on 1,151 patients with ED, 55% had experienced ED for a similar duration [35]. Our observation that participants reporting a longer duration of ED had more severe ED is consistent with similar findings in studies on treatment-seeking behavior of men with ED [36,37]. In spite of ED being a prevalent and long-standing condition, and the WAMHS having been conducted more than 3 years after sildenafil (Viagra) became commercially available in Australia for the treatment of ED, only 14.1% of the participants with ED had ever received any treatment compared with 11.6% of the adult male general medical practice attendees with ED in 1997 [4].

There is, thus, a clear need for educational programs and awareness campaigns at various levels of the community as well as within the healthcare profession. The finding that a longer history of ED was associated with ED of greater severity would provide a good rationale for encouraging men with ED to seek professional assistance early in order that therapeutic intervention may be initiated at its milder stages. The mounting evidence that ED may be a predictor or marker of cardiovascular and endothelial disease [38–40] should also serve as an incentive for ED to be comprehensively investigated.


  1. Top of page
  3. Introduction
  4. Method
  5. Results
  6. Discussion
  7. Conclusions
  8. Statement of Authorship
  9. References

The WAMHS has provided overall and age-specific prevalences of ED and various strata of severity of ED for the entire age range of the adult male population in WA. It is probable that these data are applicable to Australia nationwide.

ED is highly prevalent in WA, underdiagnosed and grossly undertreated. In a rapidly aging population, these findings will have significant implications in the planning and delivery of healthcare and social support services, and specifically for the therapy of ED.

Prevalences of ED in population-based studies should be standardized to WHO World Standard Population in order that meaningful comparisons may be made across populations with different age distributions.

Conflict of Interest: The study was conducted with an unrestricted grant from Pfizer Australia.

Statement of Authorship

  1. Top of page
  3. Introduction
  4. Method
  5. Results
  6. Discussion
  7. Conclusions
  8. Statement of Authorship
  9. References

Category 1

  • (a) 
    Conception and Design
    • Kew-Kim Chew; Bronwyn Stuckey; Konrad Jamrozik

  • (b) 
    Acquisition of Data
    Kew-Kim Chew; Carolyn Earle
  • (c) 
    Analysis and Interpretation of Data
    • Kew-Kim Chew; Alexandra Bremner

Category 2

  • (a) 
    Drafting the Article
    • Kew-Kim Chew

  • (b) 
    Revising it for Intellectual Content
    • Kew-Kim Chew; Bronwyn Stuckey; KonradJamrozik

Category 3

  • (a) 
    Final Approval of the Completed Article
    • All coauthors


  1. Top of page
  3. Introduction
  4. Method
  5. Results
  6. Discussion
  7. Conclusions
  8. Statement of Authorship
  9. References
  • 1
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    Prins J, Blanker MH, Bohnen AM, Thomas S, Bosch JLHR. Prevalence of erectile dysfunction: A systemic review of population-based studies. Int J Impot Res 2002;14:42232.
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