In total, 1122 men completed non-validated structured interviews on sexual attitudes and on erectile dysfunction treatment expectations and barriers. Dimensions of sexual attitudes and treatment expectations and barriers were extracted by factor analysis and subjects were grouped into types by cluster analysis. Five types emerged: the sensation seeker, the sensuous, the anxious, the confident and the abstinent. The majority of men agreed on the importance of sex for the partnership. For the majority of anxious, sensuous and sensation-seeking men, sex was important for self-esteem. Expecting quality of life, enjoyment, self-esteem and hard reliable erections from treatment with phosphodiesterase-5 inhibitors, anxieties for side effects and loss of control, sexual abstinence and desire for an intensive sex life had the strongest impact on the likelihood of use. Men's sexual attitudes vary considerably and impact reactions to erection difficulties. A typology of five groups was developed, which will contribute to research on and understanding of men's sexual and treatment-seeking behaviors.
Erectile dysfunction (ED) is frequent and bothersome but underreported and undertreated, despite the availability and publicity of phosphodiesterase-5 (PDE-5) inhibitors, such as sildenafil (Viagra, Pfizer Inc., New York, NY, USA), tadalafil (Cialis, Eli Lilly and Company Inc., Indianapolis, IN, USA) and vardenafil (Levitra, Bayer GmbH, Leverkusen, Germany).1, 2, 3, 4, 5 This discrepancy has stimulated extensive research on adult males' sexual attitudes, behaviors and treatment barriers.3, 6, 7, 8, 9, 10, 11
Studies of human sexuality have highlighted a large variability in men's sexual life and attitudes, and it can be expected that sexual behavior styles and beliefs affect men's reactions to erection difficulties. Grouping patients by behaviors and beliefs has been useful for designing educational campaigns and health-care interventions.12, 13, 14, 15, 16, 17 With regard to motivation for behavioral changes in other fields, brief interventions have been shown to be useful that are based on a specific state or trait markers of patients.15, 17, 18, 19, 20
Previous major studies on ED treatment-related behaviors (for example, Global Study of Sexual Attitudes and Behaviors (GSSAB),6 men's attitudes to life events and sexuality (MALES),7, 9 Cross-National Survey on Male Health Issues (CNSMHI)3, 8) reported findings for total samples and did not break down results by variation in sexual attitudes. Therefore, we aimed to analyze associations between sexual attitudes, beliefs and ED-related behaviors and to develop a typology based on such associations. Such a typology might contribute to the understanding of men's coping mechanisms and treatment-seeking behaviors and facilitate future educational activities.
The study was carried out in accordance with the International Chamber of Commerce (ICC)/ESOMAR International Code of Marketing and Social Research Practice (www.esomar.org). Compliance with these widely accepted standards secured the consideration of relevant ethical principles.
The research question was exploratory in nature, not hypothesis driven, and therefore we selected an exploratory, multistep approach. First, we aimed to identify aspects and topics relevant for ED-related behavior. After this step it was obvious that a large number and variety of beliefs and attitudes modify ED-related behavior. We then tried to condense this variability to underlying dimensions and to a typology. Finally, we analyzed beliefs and behaviors by type.
A professional research company started with a qualitative research conducted as face-to-face in-depth semi-structured interviews with 75 ED sufferers and three 4-h group discussions with ED sufferers, partners and treating physicians, respectively, all recruited by advertising, to identify themes and topics important for ED perception and treatment. In view of transcripts from these interviews, a list of items covering all relevant aspects of sexual life, perception and treatment of ED were constructed and grouped by topics. This list was reviewed for redundancy and content validity by psychologists experienced in questionnaire development and condensed to two sets of 42 items covering attitudes to love and sexuality and treatment expectations and barriers, and transformed into a forced-decision four item Likert format (‘completely agree’ ‘agree’ ‘do not agree’ ‘do not agree at all’ or ‘extremely important’ ‘important’ ‘less important’ ‘not important at all’).
Five experts in social and medical sciences performed a semantic analysis of both lists of items, including assessment of association patterns. In view of this analysis, wording of individual items was revised. Apart from this semantic examination, no further analyses to assess the psychometric quality of the structured interview were performed.
A market research company recruited a nationwide sample of men aged 30–70 years. Sampling was stratified to include about 25% of men from each age decade (30–39, 40–49, 50–59, 60–70), 50% with self-identified ED and about one-third of them having used a PDE-5 inhibitor. Participants were selected to be representative for the German general male population concerning geographic and other socio-demographic variables, including marital status, household size, number of children, education, occupation, income and community size.
Participants completed 30 min face-to-face at-home interviews on sexuality and erection problems conducted by professionally trained male interviewers. The structured interview covered general questions on socio-demographic variables, concomitant disorders and medication, sexual attitudes and behaviors, erection problems and treatment. Self-identified ED was defined as answering ‘yes’ to the question ‘Do you suffer from erection problems/ED?’. Participants were asked about actual and prior PDE-5 inhibitor usage and the likelihood of using such drugs in case they were affected by ED (1=very likely, 2=likely, 3=unlikely, 4=very unlikely). In addition, the two batteries about attitudes to love and sexuality, and treatment expectations and barriers were applied.
To extract dimensions of attitudes as well as expectations and barriers, both 42-item sets were subjected to principal component analysis with orthogonal VARIMAX rotation. Factors with eigenvalues >1 were selected. Extracted attitudes factors were correlated with expectations and barriers factors. Statistically significant (P<0.01) associations that allowed meaningful interpretation based on the previous qualitative research from the interviews conducted for the development of the structured interview were selected to define types. Selected associations were seeded into procrustes cluster analysis to assign each participant to a specific type based on his individual factor value pattern.
Thereafter, answers to questions on attitudes, expectations and barriers, ED perception and treatment were analyzed descriptively by type.
Multiple linear regression was used to analyze the relationship between likelihood of using PDE-5 inhibitors (dependent variable) and both sets of factor values (attitudes as well as expectations and barriers).
Exploratory individual interviews and group discussion identified the following relevant topics: socio-demography, health status, health-related behavior, sexual attitudes and behaviors, ED perception, ED-related interactions with health-care professionals, perception of and experience with ED treatments and communication on ED.
In total, 1122 structured interviews were completed in September 2004. Among whom, 524 participants (46.7%) had erection problems of whom 185 (35.3%) had taken PDE-5 inhibitors (152 sildenafil, 30 tadalafil and 18 vardenafil).
Factor structures and typology
Principal component analysis of attitudes to love and sexuality yielded eight factors with eigenvalues >1, explaining 52% of variance. Interpretation of factors, items with the highest factor loadings and explained variance, are shown in Table 1. Treatment expectations and barriers was also reduced to eight factors with eigenvalues >1, explaining 59% of variance (Table 1).
Five statistically significant and meaningfully interpretable association patterns were selected among correlations between attitudes factors and expectations and barriers factors. Interpretation of these associations as types is shown in Table 2. In view of individuals' factor values, every subject was grouped to one of the types resulting in following distribution of types (% of sample): the sensation seeker 27%, the sensuous 17%, the anxious 20%, the confident 20% and the abstinent 17%. The types differed by age group and prevalence of self-identified ED.
Attitudes, perceptions, expectations and barriers
Sexual attitudes concerning partnership and self-esteem with >50% agreements in the total sample are shown in Figure 1. The most important variations across types are seen with regard to the importance of sex, impact of sex on self-esteem and issues of potency.
Two-third of men did not perceive ED predominantly as a medical condition: 28% regarded erection problems primarily as a natural consequence of aging, 26% as a phenomenon that can easily be settled and 12% as transient disturbance that does not deserve special attention. ED was first and foremost addressed as medical condition by 22%, whereas 12% regarded it mainly as sequel of another disease (Figure 2).
Psychological stress (61.4%), organic disease (58.2%) and aging (55.6%) were the most frequently cited likely causes of ED without marked differences between types. ED treatment expectations with >75% agreements in the total sample are shown in Figure 3. In all, 54.6% of sensation seekers, 64.6% of sensuous and 57.0% of anxious rated the opportunity to purchase a treatment anonymously as important, 65.8, 72.9 and 67.0% the availability without prescription. For confident and abstinent, the agreement to these two statements was well below 50%.
The group of 524 men with self-identified ED comprised 126 sensation seekers, 91 sensuous, 165 anxious, 56 confident and 86 abstinent. Reasons for not using ED treatments in this group with >50% agreements are shown in Figure 4.
Table 3 shows contact persons and information sources men would use in case affected by ED. On average, approximately 10% more would talk to their general practitioners than to their partners.
In all, 16.5% of the sample had already used a PDE-5 inhibitor, 5.8% were current users, 21.9% classified it as very likely to take such a compound in case affected by ED and 32.5% as likely. Among men with self-identified ED, 29.0% had already taken sildenafil (46.8% of sensation seekers, 26.4% of sensuous, 29.7% of anxious, 16.1% of confident and 12.8% of abstinent). For tadalafil, the percentages are 5.7% (7.1, 7.7, 7.9, 0 and 1.2%), and for vardenafil 3.4% (4.0, 4.4, 3.6, 3.6 and 1.2%).
Expecting quality of life, enjoyment and self-esteem from treatment (standardized regression coefficient 0.27), fear of side effects and loss of control (−0.25), sexual abstinence and disinterest (−0.23), expecting hard reliable erections from treatment (0.19) and desire for an intensive and excessive sex life (0.17) had the strongest impact on the likelihood to use PDE-5 inhibitors (all P<0.0001).
We developed a typology based on sexual attitudes, ED treatment expectations and barriers that aimed to facilitate understanding of ED-related behavior and approaching sufferers. We saw relevant differences between types not only in the attitudes the types were based on but also in the perception of ED and in PDE-5 inhibitor usage. There are some limitations to our study results, which require special attention.
First, owing to the explorative and qualitative nature of our research questions and study goals, which were neither inferential, confirmative nor quantitative, we choose an iterative, exploratory study design with the focus on variety of topics and associations covered, not on accuracy of metrics. In line with this principles of qualitative research, the sample was not fully representative for the general male population in certain variables, the structured interview was not subjected to a validating procedure (for example, establishing test–retest and inter-rater reliability, internal and external validity), and only meaningful interpretable association were used for cluster analysis. As a consequence, results should be interpreted qualitatively, not quantitatively. This is fully in accordance with comparable research settings that have yielded important insights into perceptual and motivational aspects of ED treatment.3, 6, 7, 8, 9, 21, 22, 23
Second, our procedure to define types was empirically and heuristically based. In contrast to classical cluster analysis techniques, we a priori defined types as prototypical patterns of attitudes based on empirically established correlations between the two sets of attitudinal factors, and then performed cluster analysis. The main advantage of choosing this procedure is that it allows grouping subjects according to a specific research question. The reason for not choosing the classical cluster analysis techniques was that they tend to be susceptible to response sets, complicating textual interpretation of the resulting types.
Third, based on the low percentage of men actually treated for ED in Germany, we selected an age-stratified sample with oversampling of treated and untreated ED sufferers. This was to allow an in-depth analysis of barriers and drivers for ED treatment-seeking behavior. Therefore, absolute percentages are not inferable to the general population. However, this oversampling enabled us to detect associations and differences between types that are useful for individual patient counseling and the design of educational activities.
Furthermore, all findings reported here are based on a survey of German men. Results should be generalized to other nationalities only with caution, owing to the probably high potentially language and culture sensitivity of the discussed issue of sexuality.
Despite these premises our data add to the existing literature of treatment-seeking behavior:
First, following our typology approach, we saw differences in the types not only with regard to their attitudes the types were based on, but also in the perception of ED and in PDE-5 inhibitor usage. This observation not only supports the validity of the typology itself but also its likely usefulness for understanding ED-related behavior. It also warrants future research to explore whether these types respond differentially to educational approaches. It might be important for the practitioner to have specific brief interventions by type to help to motivate patients to initiate or continue with treatment.
Second, according to our data the most important aspect of sexuality is its role for the partnership. More than 80% of men agreed on statements on the partnership-enhancing function of sex. This finding is in agreement with previous studies.24, 25 The strong interrelation of partnership and sexuality was also shown in a recent study by Corona et al.,26 who reported that characteristics of the relation and the partner are associated with sexual dysfunction. Accordingly, sexual dysfunction must always be seen from a partnership perspective and the likely effect of interventions on the partnership should receive adequate attention. Successful treatment of ED with the PDE-5 inhibitors has been shown to improve the partners' quality of sexual life and the quality of partnership.27, 28, 29, 30, 31 Following the typology, a satisfying sex life was a significantly more important constituent of a partnership for sensation seekers and sensuous than for the other types in our sample.
Third, erectile function in general has been linked to self-esteem in many studies.21, 32, 33, 34 We saw this association for sensation seekers, sensuous and anxious, whereas confident and abstinent apparently had disconnected self-confidence from potency issues. Therefore, it would be interesting to analyze the reported beneficial effects of ED treatment on self-esteem34 by type.
Fourth, expecting quality of life, better sex and self-esteem, and hard reliable erections from ED treatment were the most important predictors increasing likelihood of PDE-5 inhibitor usage. Recent trials have highlighted that sildenafil potentiates pudendal artery blood flow and penile oxygenation, thereby helping men with ED achieving completely hard (grade 4) erections. Erection hardness was correlated with sexual satisfaction and improvement of self-esteem.35, 36, 37 Addressing this aspect, which might be new to most physician–patient communication, could therefore encourage sufferers to seek or continue medical care.
Fifth, perceived risks of ED treatment, mostly baseless from an evidence-based point of view, were found to be among the most important barriers discouraging sufferers from seeking ED treatment in our study as well as in previous surveys.9, 38 Apparently, the publicity of PDE-5 inhibitors and the unlimited availability of information through the Internet have not been able to communicate a balanced, objective understanding of such an important sexual health topic like treatment options for ED. This observation underscores the importance of low-threshold access to balanced information for patients with sexual dysfunction. A recent prospective study of the German Information Center for Sexuality and Health (ISG e.V.), based at Freiburg University Medical Center, found that of those who received a written information package about ED almost one in two intended to take an action with regard to their problem.39 The quality rating for that written information material was very high. After 3–6 months, more than those who had initially planned an action had taken steps.40, 41 Comparable experiences have been reported from other European help-lines.42, 43, 44
Men's sexual attitudes vary considerably and impact reactions to erection difficulties. A typology of five groups was developed that will contribute to research into and understanding of men's sexual and treatment-seeking behaviors and can contribute to the design of educational activities. For example, interpreting the typology regarding educational approaches that can motivate men to seek medical care, the sensation seeker appears to be most attracted by the functional treatment benefit of a hard reliable erection, the sensuous would respond best to the partnership and emotional benefits of a natural, well-tolerated ED treatment and the anxious is looking for a well tolerated, fast and easy resolution of his problem. The confident and the abstinent appear to be more difficult or even resistant to be motivated.
Braun M, Wassmer G, Klotz T, Reifenrath B, Mathers M, Engelmann U . Epidemiology of erectile dysfunction: results of the ‘Cologne Male Survey’. Int J Impot Res 2000; 12: 305–311.
Levy L, Guiliano F, Allaert FA, Girerd X, Pouchain D, Schaetz D et al. Screening for erectile dysfunction in an at-risk population. J Sex Med 2005; 2 (Suppl 1): 53.
Shabsigh R, Perelman MA, Laumann EO, Lockhart DC . Drivers and barriers to seeking treatment for erectile dysfunction: a comparison of six countries. BJU Int 2004; 94: 1055–1065.
Buddeberg C, Bucher T, Hornung R . Erektile Dysfunktion bei Männern in der zweiten Lebenshälfte. Urologe 2005; 44: 1045–1051.
Berner M, Kriston L, Harms A . Efficacy of PDE-5-inhibitors for erectile dysfunction. A comparative meta-analysis of fixed-dose regimen randomized controlled trials administering the International Index of Erectile Function in broad spectrum populations. Int J Impot Res 2006; 18: 229–235.
Hartmann U, Niccolosi A, Glasser DB, Gingell C, Buvat J, Moreira E et al. Sexualität in der Arzt-Patient-Kommunikation. Ergebnisse der Globalen Studie zu sexuellen Einstellungen und Verhaltensweisen. Sexuologie 2002; 9: 50–60.
Rosen RC, Fisher WA, Eardley I, Niederberger C, Nadel A, Sand M . The multinational Men's Attitudes to Life Events and Sexuality (MALES) study: I. Prevalence of erectile dysfunction and related health concerns in the general population. Curr Med Res Opin 2004; 20: 607–617.
Perelman M, Shabsigh R, Seftel A, Althof S, Lockhart D . Attitudes of men with erectile dysfunction: a cross-national survey. J Sex Med 2005; 2: 397–406.
Fischer WA, Rosen RC, Eardley I, Niederberger C, Nadel A, Kaufman J . The Multinational Men's Attitudes to Life Events and Sexuality (MALES) Study Phase II: Understanding PDE-5-inhibitor treatment seeking patterns, among men with erectile dysfunction. J Sex Med 2004; 1: 150–160.
Hartmann U, Burkart M . Erectile dysfunctions in patient–physician-communication: optimized strategies for addressing sexual issues and the benefit of using a patient questionnaire. J Sex Med 2007; 4: 38–46.
Stamogiannou I, Grunfeld EA, Denison K, Muir G . Beliefs about illness and quality of life among men with erectile dysfunction. Int J Impot Res 2005; 17: 142–147.
Ha BT, Jayasuriya R, Owen N . Predictors of men's acceptance of modern contraceptive practice: study in rural Vietnam. Health Educ Behav 2005; 32: 738–750.
Holden CA, McLachlan RI, Cumming R, Wittert G, Handelsman DJ, de Kretser DM et al. Sexual activity, fertility and contraceptive use in middle-aged and older men: Men in Australia, Telephone Survey (MATeS). Human Reprod 2005; 20: 3429–3434.
Richters J, Grulich AE, de Visser RO, Smith AM, Rissel CE . Sex in Australia: autoerotic, esoteric and other sexual practices engaged in by a representative sample of adults. Aust N Z J Public Health 2003; 27: 180–190.
Migneault JP, Adams TB, Read JP . Application of the transtheoretical model to substance abuse: historical development and future directions. Drug Alcohol Rev 2005; 24: 437–448.
Herlitz C, Ramstedt K . Assessment of sexual behavior, sexual attitudes, and sexual risk in Sweden (1989–2003). Arch Sex Behav 2005; 34: 219–229.
Tierney DW, McCabe MP . The utility of the trans-theoretical model of behavior change in the treatment of sex offenders. Sex Abuse 2005; 17: 153–170.
Bien TH, Miller WR, Tonigan JS . Brief interventions for alcohol problems: a review. Addiction 1993; 88: 315–335.
Bertholet N, Daeppen J-B, Wietlinsbach V, Fleming M, Burnand B . Reduction of alcohol consumption by brief alcohol intervention in primary care. Arch Intern Med 2005; 165: 986–995.
Berner MM, Härter M, Zeidler C, Kriston L, Mundle G . German general practitioners' perceived role in the management of alcohol use disorders: responsible but undertrained. Prim Care Community Psychiatr 2006; 11: 29–35.
Tomlinson J, Wright D . Impact of erectile dysfunction and its subsequent treatment with sildenafil: qualitative study. BMJ 2004; 328: 1037–1041.
Hanson-Divers C, Jackson SE, Lue TF, Crawford SY, Rosen RC . Health outcomes variables important to patients in the treatment of erectile dysfunction. J Urol 1998; 159: 1541–1547.
Low WY, Wong YL, Zulkifli SN, Tan HM . Malaysian cultural differences in knowledge, attitudes and practices related to erectile dysfunction: focus group discussions. Int J Impot Res 2002; 14: 440–445.
Pfizer Inc.. The Pfizer Global Study of Sexual Attitudes and Behaviours, New York, NY, USA.
Rissel CE, Richters J, Grulich AE, de Visser RO, Smith AM . Sex in Australia: attitudes towards sex in a representative sample of adults. Aust N Z J Public Health 2003; 27: 118–123.
Corona G, Petrone L, Mannucci E, Magini A, Lotti F, Ricca V et al. Assessment of the relational factor in male patients consulting for sexual dysfunction: the concept of couple sexual dysfunction. J Androl 2006; 27: 795–801.
Heiman JR, Talley DR, Bailen JL, Shumel B, Pace CR, Creanga DL et al. Female partners of men with erectile dysfunction treated with sildenafil citrate report greater satisfaction and enjoyment from sexual intercourse: a multicenter, randomize, double-blind, placebo-controlled study. J Urol 2005; 173 (4 Suppl): 5.
Muller MJ, Ruof J, Graf-Morgenstern M, Porst H, Benkert O . Quality of partnership in patients with erectile dysfunction after sildenafil treatment. Pharmacopsychiatry 2001; 34: 91–95.
Fisher WA, Rosen RC, Mollen M, Brock G, Karlin G, Pommerville P . Improving the sexual quality of life of couples affected by erectile dysfunction: a double-blind, randomized, placebo-controlled trial of vardenafil. J Sex Med 2005; 2: 699–708.
Goldstein I, Fisher A, Sand M, Rosen RC, Mollen M, Brock G et al. Women's sexual function improves when partners are administered vardenafil for erectile dysfunction: a prospective, randomized, double-blind, placebo-controlled trial. J Sex Med 2005; 2: 819–832.
Edwards D, Hackett G, Collins O, Curram J . Vardenafil improves sexual function and treatment satisfaction in couples affected by erectile dysfunction (ED): a randomized, double-blind, placebo-controlled trial in PDE5 inhibitor-näive men with ED and their partners. J Sex Med 2006; 3: 1028–1036.
Althof SE . Quality of life and erectile dysfunction. Urology 2002; 59: 803–810.
Hoesl CE, Woll EM, Burkart M, Altwein JE . Erectile dysfunction (ED) is prevalent, bothersome and underdiagnosed in patients consulting urologists for Benign Prostatic Syndrome (BPS). Eur Urol 2005; 47: 551–557.
Cappelleri JC, Althof SE, Siegel RL, Shpilsky A, Bell SS, Duttagupta S . Development and validation of the self-esteem and relationship (SEAR) questionnaire in erectile dysfunction. Int J Impot Res 2004; 16: 30–38.
Wayman C, Hornby S, Burden A, Casey J . Sildenafil increases erection hardness by potentiating pudendal artery blood flow and intracavernosal pressure in the anaesthesised dog. J Sex Med 2006; 3 (5 Suppl): 393.
Wayman C, Hornby S, Burden A, Casey J . Sildenafil increases erection hardness by improved penile oxygenation in the anaesthesised dog. J Sex Med 2006; 3 (5 Suppl): 397.
Jünemann KP, Levinson IP, Creanga DL . VIAGRA (sildenafil citrate) 100 mg helps men with erectile dysfunction achieve completely hard erections and improved sexual intercourse success, enjoyment, and satisfaction. J Sex Med 2006; 3 (5 Suppl): 423.
Son H, Park K, Kim SW, Paick JS . Reasons for discontinuation of sildenafil citrate after successful restoration of erectile function. Asian J Androl 2004; 6: 117–120.
Günzler C, Kriston L, Stodden V, Leiber C, Berner MM . Can written information material help to increase treatment motivation in patients with erectile dysfunction? – a survey of 1188 men. Int J Impot Res 2007; 19: 330–335.
Stodden V, Berner MM . Comorbidity and treatment patterns in patients with erectile dysfunction. Int J Impot Res 2002; 14 (Suppl 4): 4.
Berner MM, Dieken J, Kriston L, Wetterauer U . Communication, initiative and effective treatment as determinants of sexual satisfaction in patients with ED and their partners. Int J Impot Res 2003; 15 (Suppl 6): 48.
Papaharitou S, Nakopoulou E, Kirana P, Iraklidou M, Athanasiadis L, Hatzichristou D . Women's sexual concerns: data analysis from a help-line. J Sex Med 2005; 2: 652–657.
Bos AR, Visser GC, Tempert BF, Schaalma HP . Evaluation of the Dutch AIDS information helpline: an investigation of information needs and satisfaction of callers. Patient Educ Couns 2004; 54: 201–206.
Fugl-Meyer KS, Arrhult H, Pharmanson H, Backman AC, Fugl-Meyer AM, Fugl-Meyer AR . A Swedish telephone help-line for sexual problems: a 5-year survey. J Sex Med 2004; 1: 278–283.
The study was initiated and funded by Pfizer Pharma GmbH, Karlsruhe, Germany. Michael Berner has received honoraria and research funds from Bundesministerium für Bildung und Forschung, Bayer, Böhringer Ingelheim, Lilly, Pfizer and Willmar Schwabe. Sinus sociovision GmbH, Heidelberg, Germany, conducted the study. Martin Burkart is an employee of Pfizer Pharma GmbH, Karlsruhe, Germany.
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Berner, M., Plöger, W. & Burkart, M. A typology of men's sexual attitudes, erectile dysfunction treatment expectations and barriers. Int J Impot Res 19, 568–576 (2007). https://doi.org/10.1038/sj.ijir.3901571
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