995
ORIGINAL RESEARCH—OUTCOMES ASSESSMENT Psychometric Properties of the Iranian Version of the Female Sexual Distress Scale-Revised in Women Elham Azimi Nekoo, MD,* Andrea Burri, MSc,† Farzaneh Ashrafti, MSc,‡ Bengt Fridlund, PhD,§ Harold G. Koenig, MD,¶** Leonard R. Derogatis, PhD,†† and Amir H. Pakpour, PhD‡‡§§ *Vali-e-Asr Reproductive Health Research Center, Tehran University of Medical Sciences, Tehran, Iran; †Department of Psychology, University of Zurich, Zurich, Switzerland; ‡Neurology Research Center and Department of Midwifery, School of Nursing and Midwifery, Kerman University of Medical Sciences, Kerman, Iran; §School of Health Sciences, Jönköping University, Jönköping, Sweden; ¶Departments of Medicine and Psychiatry, Duke University Medical Center, Durham, NC, USA; **Department of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia; ††Center for Sexual Medicine at Sheppard Pratt and Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA; ‡‡ Social Determinants of Health Research Center, Qazvin University of Medical Sciences, Qazvin, Iran; §§Department of Public Health, Qazvin University of Medical Sciences, Qazvin, Iran DOI: 10.1111/jsm.12449
ABSTRACT
Introduction. Several tools for the assessment of sexuality-related distress are now available. The Female Sexual Distress Scale (FSDS) and its revised version (FSDS-R) are extensively validated and among the most widely used tools to measure sexually related personal distress. Aim. The aim of the study was to determine the psychometric properties of the Iranian version of the FSDS-R in a population sample of Iranian women. Methods. A total of 2,400 married and potentially sexually active women were recruited and categorized into three groups including (i) a healthy control group; (ii) a group of women with hypoactive sexual desire disorder (HSDD); and (iii) a group of women suffering from other female sexual dysfunction (FSD). Participants were asked to complete a set of questionnaires including the Iranian version of the Female Sexual Function Index (FSFI-IV), the FSDS-R, and the Hospital Anxiety and Depression Scale. Main Outcome Measures. Sexuality-related distress and FSD as assessed by the Iranian version of the FSDS-R and the FSFI-IV are the main outcome measures. Results. Internal consistencies and test–retest reliability of the FSDS-R across the three assessments points for the three groups were >0.70. The FSDS-R correlated significantly with anxiety, depression, and the FSFI total score. Significant differences in the FSDS-R scores were found between healthy women, women with HSDD, and women with other types of FSD. Factor analysis of the FSDS-R yielded a single-factor model with an acceptable fit. Conclusions. The Persian version of the FSDS-R is a valid and reliable instrument for the assessment of sexualityrelated distress in Iranian women and can be used to screen patients with HSDD. Azimi Nekoo E, Burri A, Ashrafti F, Fridlund B, Koenig HG, Derogatis LR, and Pakpour AH. Psychometric properties of the Iranian version of the Female Sexual Distress Scale-Revised in women. J Sex Med 2014;11:995–1004. Key Words. Female Sexual Distress Scale-Revised; Iranian Version; Sexually Related Personal Distress; Psychometrics
Introduction
F
emale sexual dysfunction (FSD) refers to the various ways in which a woman is unable to participate in a sexual relationship or experience
© 2014 International Society for Sexual Medicine
sexuality the way she would wish [1]. According to current classification systems, FSD includes disorders of sexual desire, arousal, orgasm, and pain [2]. Prevalences of up to 50% for female sexual complaints have been reported, with estimates difJ Sex Med 2014;11:995–1004
996 fering across populations and cultures [3]. In Iran, epidemiologic studies conducted on women aged between 16 and 71 years have found prevalences of sexual complaints to range from 20% to 50%, depending on the specific sexual problem [4,5]. In addition, a recent study conducted by Ghanbarzadeh et al. found that 39% women (n = 694) reported not feeling any pleasure during their sexual activity and/or during vaginal intercourse [6]. Despite increasing research efforts over the last decades, the current state of knowledge regarding the underlying causes of FSD remains limited [7]. A wealth of cross-national epidemiologic studies have suggested numerous demographic, psychological, and physiological “risk factors” including age, education, mental and physical health, anatomical factors, hormones, genes, etc., thought to be associated with the development and maintenance of FSD [8,9]. However, no clear mechanisms as what causes FSD have emerged yet. In spite of considerable advances in creating conceptual frameworks for FSD, controversies regarding accurate clinical definitions and a uniform classification of FSD exist [10]. According to the Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM-5 criteria) and the American Urological Association Foundation, personal distress is considered one of the key criteria in the diagnoses of FSD [2,11,12]. Accordingly, a woman should show evidence of significant personal distress, characterized by negative feelings and anxiety about one’s sexuality or sexual activities, in relation to her sexual problem to qualify for the diagnosis of FSD. However, quantitative evidence questions the utility of personal sexual distress as a primary diagnostic indicator of FSD, and experts have been unable to reach consensus on whether or not to include distress as a diagnostic key criterion [13–16]. To guarantee an accurate definition of FSD, as well as adequate evaluation and comparability of population-based prevalences, the presence and the degree of distress related to the sexual problem should also be assessed and evaluated when conducting epidemiologic studies on FSD. Generalization of results from epidemiologic studies on FSD to all settings and cultures, especially when based on DSM-derived definitions and diagnostic criteria, is discouraged [17]. Paykel, for example, argued that the DSM is substantially Western based and hence does not consider other syndromes and conditions that influence a woman’s J Sex Med 2014;11:995–1004
Azimi Nekoo et al. sexuality that may be much more prevalent across other cultures [17]. In view of this, the availability of culturally adapted questionnaires that allow the assessment of FSD and sexuality-related distress is crucial. Several tools for the assessment of sexualityrelated distress are now available, such as the Female Sexual Distress Scale (FSDS) [18], the Sexual Desire Relationship Distress Scale [19], and the Decreased Sexual Desire Screener [20]. The most extensively validated and widely used tool for assessing sexuality-related distress in women is the FSDS [21,22]. Recently, a revised version of the FSDS—the FSDS-R—has been developed offering an increased sensitivity–specificity profile of the instrument. The FSDS-R has already been translated into several languages and validated in numerous populations and cultures [21–24]. However, a Persian version of the tool is missing. The purpose of this study, then, was to determine the psychometric properties of the Iranian version of the FSDS-R in a population of Iranian women.
Material and Methods
Sample The study sample consisted of women who had been referred to 10 urban health centers in Qazvin (a city near Tehran) by their general practitioner. A total of 2,400 randomly selected, married, and potentially sexually active women (based on information available from their medical records) were contacted. To participate in the study, women had to be 18 years or older; able to read, speak, and understand Persian/Farsi; married; sexually active; not suffering from any chronic disease (e.g., diabetes mellitus, cardiovascular diseases, hypertension, renal failure, cancer); not taking any antihypertensives, antidepressants, antihistamines, and/or benzodiazepines; not suffering from alcoholism (as assessed by the Alcohol Use Disorders Identification Test) and/or drug and substance abuse; not suffering from depression according to the Hospital Anxiety and Depression Scale (HADS); and not taking any antipsychotic medication. Women using oral contraceptive pill, women with sexual aversion disorder, dyspareunia, vaginismus, gender identity disorder, and/or any paraphilia were excluded from the study. Also excluded were women who were pregnant or 3 months postpartum, undergoing hysterectomy and/or mastectomy, suffering from obesity (body
Female Sexual Distress in Iranian Women mass index [BMI] ≥ 30 kg/m2), or have had a colostomy and/or oophorectomy. Of the 2,400 women contacted, 243 (10.1%) women refused to participate. Of the remaining 2,157, 191 did not meet the inclusion criteria, resulting in a final sample of 1,966 women. Those women agreeing to participate were screened for FSD based on the DSM-IV-TR criteria by two gynecologists. Based on this screening, women were assigned to either the healthy control group or to the FSD case group. Women assigned to the FSD case group were further divided into the hypoactive sexual desire disorder (HSDD) group [25] or the “any other” FSD group. The study protocol was approved by the Ethics Committee of Qazvin University of Medical Sciences, and all women provided written informed consent.
Translation and Cultural Adaptation Procedure The procedure followed to create an Iranian version of the FSDS was equivalent to the one followed for the original English version and suggested by Wild et al., Beaton et al., and Acquadro et al. [26–28]. In the first step, the English version was translated into Persian/Farsi after obtaining permission from the developer of the FSDS-R. Two bilingual translators with Persian/Farsi mother tongue translated the English FSDS into Persian independently from each other. Two other translators, along with the local project manager (A.H. Pakpour), then compared these translations and reconciled them into one Persian/Farsi version. The second step involved a backward translation into English. Two native Englishspeaking translators (bilingual with Persian/Farsi) translated the Persian/Farsi version back into English. These translators were unfamiliar with the original version of the FSDS or its intention or concept. Third, the backward translated versions were then compared with the original English version by the local project manager to ensure that the Persian/Farsi version reflected the same item content as the original English version. In the end, an expert committee including methodologists, biostatisticians, gynecologists, nurses, psychologists, health psychologists, and midwives reviewed the translations, removed any discrepancies, and agreed on a final Persian/Farsi version. Four types of equivalences (semantic, idiomatic, experiential, and conceptual) were considered in this final version. Next, this final Persian/Farsi version was administered to n = 27 women reporting sexual distress (mean age 35 ± 22 years) and to n = 34 healthy women (and not reporting any dis-
997 tress; mean age 37 ± 51 years) to test the conceptual equivalence of the Persian/Farsi version and to assess whether the questionnaire and its items was acceptable, understandable, and appropriate (i.e., cognitive debriefing). A face-to-face interview was performed where respondents were asked to highlight problems in understanding the items and to express their opinions on the item content. Finally, the resulting Persian/Farsi version of the FSDS-R was administrated to the 1,966 women agreeing to participate in the field testing. All of these 1,966 participants were then asked to complete the study tools at three time points: at baseline (after providing written consent), 7 days, and 28 days after baseline assessment.
Measures Socio-Demographic Information Among the socio-demographic characteristics assessed were age, education, husband’s education, duration of marriage, monthly family income, occupation, smoking status, having children, BMI, and duration of menstruation. Standing height was measured without shoes to the closest of 0.5 cm with a calibrated stadiometer, and body weight was measured in light clothes to the closest of 10 g with a calibrated digital scale. BMI was then calculated as weight (kg)/height (m)2. Female Sexual Function Index (FSFI) The Female Sexual Function Index (FSFI) consists of 19 items that cover 6 domains of women’s sexual functioning including sexual desire (2 items), arousal (4 items), lubrication (4 items), orgasm (3 items), satisfaction (3 items), and pain (3 items). All items are scored on a five-point Likert-type scale ranging from 0 (or 1) to 5, with higher scores indicating better sexual functioning [29,30]. FSDS-R The FSDS-R is a self-reported questionnaire consisting of 13 items assessing different aspects of sexual activity-related distress in women [24]. All items are scored on a five-point Likert-type scale ranging from 0 (never) to 4 (always), with higher score indicating more sexual distress. A total score can be computed by adding all 13 item scores [24]. The original version of the FSDS-R demonstrated acceptable scale reliability with Cronbach’s alpha values ranging from α = 0.87 to α = 0.93 and high test–retest reliability (intra-class correlation coefficient ranging from r = 0.74 to r = 0.86) [24]. Furthermore, a unidimensional structure of the J Sex Med 2014;11:995–1004
998 FSDS-R was confirmed by confirmatory factor analysis (CFA) with a cutoff score of ≥11 used to discriminate between women reporting sexual distress and those not reporting any sexuality-related personal distress [23,24].
HADS The HADS is a brief self-report measure used to assess the severity of depressive or anxiety symptoms [31]. The HADS consists of 14 items and two subscales measuring depression (7 items) and anxiety (7 items). Each item is scored on a fourpoint Likert-type scale ranging from 0 to 3, with higher scores indicating more symptoms. A total score for each subscale can be derived by adding up all seven scale items and is categorized as follows: normal (0–7), mild (8–10), moderate (11– 14), and severe (15–21) symptoms of anxiety or depression, respectively. The HADS has been applied extensively across many studies and has been found to be highly reliable and to have excellent validity [32]. The validity and reliability of the Iranian version of the HADS have also been established in a sample of the Iranian patients with breast cancer and been considered excellent [33]. Statistical Analysis To determine the reliability of the FSDS-R, internal consistency and test–retest reliability were assessed. Alpha coefficients (α) were determined as an indicator of internal consistency, while test– retest reliability was estimated using intra-class correlation coefficients (ICCs). An internal consistency of α ≥ 0.70 was considered acceptable [34]. A two-way random effects analysis of variance was performed to examine the test–retest stability of the measure at baseline, after 7 days, and after 28 days. An intra-class correlation coefficient of ≥0.70 was considered acceptable [34]. Convergent validity was examined by computing the inter-correlations between the FSDS total score, the FSFI subscale and total score, and the HADS subscale scores. It was assumed that women with lower sexual functioning suffered from more sexual distress, depression, and anxiety [35,36]. Furthermore, correlation coefficients between the specific questionnaire items and the total score of the FSDS were calculated to assess the construct validity of the FSDS-R. To explore the discriminant validity of the FSDS-R, known-groups comparisons based on their sexual health status (healthy, HSDD, and other types of FSD) were performed among the J Sex Med 2014;11:995–1004
Azimi Nekoo et al. three groups of women. The known-group method tests the ability of the FSDS-R to differentiate between groups with known different sexual health status. It was assumed that women with any type of sexual complaints would report higher FSDS scores compared with healthy women. An analysis of covariance (ANCOVA)—adjusted for age, education, and duration of marriage—was performed to compare the FSDS-R scores between the known groups. In addition to the known-group method, a receiver operating characteristic (ROC) curve was used to determine the optimal cutoff values of the FSDS-R to discriminate between participants with sexual distress (i.e., women with HSDD) and healthy women without sexual distress. The area under curve (AUC), a measure of the degree of information the test contains over its entire score range, was also calculated. An AUC of 0.5 indicates the inability of the measure to discriminate between subgroups of the participants, while an AUC of 1.0 represents perfect discriminant validity [37]. CFA was performed to assess the construct validity of the FSDS-R using LISREL version 8.80 (Scientific Software International, Chicago, IL, USA). Because of the ordinal nature of the data, a weighted least squares with polychoric correlations and asymptotic covariances matrices was used to estimate the model parameters. Three categories of model fit indices were considered to test the fit of the original one-factor model to the data, including absolute fit indices, incremental fit indices, and parsimony fit indices. For the absolute fit indices, the model chi-square (χ2), the root mean square error of approximation (RMSEA), goodness-of-fit statistic (GFI), and standardized root mean square residual (SRMR) were used. The incremental fit indices included the comparative fit index (CFI) and the non-normed fit index (NNFI, also known as the Tucker–Lewis index). Finally, the parsimonious normed fit index (PNFI) was also assessed. An RMSEA value
ORIGINAL RESEARCH—OUTCOMES ASSESSMENT Psychometric Properties of the Iranian Version of the Female Sexual Distress Scale-Revised in Women Elham Azimi Nekoo, MD,* Andrea Burri, MSc,† Farzaneh Ashrafti, MSc,‡ Bengt Fridlund, PhD,§ Harold G. Koenig, MD,¶** Leonard R. Derogatis, PhD,†† and Amir H. Pakpour, PhD‡‡§§ *Vali-e-Asr Reproductive Health Research Center, Tehran University of Medical Sciences, Tehran, Iran; †Department of Psychology, University of Zurich, Zurich, Switzerland; ‡Neurology Research Center and Department of Midwifery, School of Nursing and Midwifery, Kerman University of Medical Sciences, Kerman, Iran; §School of Health Sciences, Jönköping University, Jönköping, Sweden; ¶Departments of Medicine and Psychiatry, Duke University Medical Center, Durham, NC, USA; **Department of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia; ††Center for Sexual Medicine at Sheppard Pratt and Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA; ‡‡ Social Determinants of Health Research Center, Qazvin University of Medical Sciences, Qazvin, Iran; §§Department of Public Health, Qazvin University of Medical Sciences, Qazvin, Iran DOI: 10.1111/jsm.12449
ABSTRACT
Introduction. Several tools for the assessment of sexuality-related distress are now available. The Female Sexual Distress Scale (FSDS) and its revised version (FSDS-R) are extensively validated and among the most widely used tools to measure sexually related personal distress. Aim. The aim of the study was to determine the psychometric properties of the Iranian version of the FSDS-R in a population sample of Iranian women. Methods. A total of 2,400 married and potentially sexually active women were recruited and categorized into three groups including (i) a healthy control group; (ii) a group of women with hypoactive sexual desire disorder (HSDD); and (iii) a group of women suffering from other female sexual dysfunction (FSD). Participants were asked to complete a set of questionnaires including the Iranian version of the Female Sexual Function Index (FSFI-IV), the FSDS-R, and the Hospital Anxiety and Depression Scale. Main Outcome Measures. Sexuality-related distress and FSD as assessed by the Iranian version of the FSDS-R and the FSFI-IV are the main outcome measures. Results. Internal consistencies and test–retest reliability of the FSDS-R across the three assessments points for the three groups were >0.70. The FSDS-R correlated significantly with anxiety, depression, and the FSFI total score. Significant differences in the FSDS-R scores were found between healthy women, women with HSDD, and women with other types of FSD. Factor analysis of the FSDS-R yielded a single-factor model with an acceptable fit. Conclusions. The Persian version of the FSDS-R is a valid and reliable instrument for the assessment of sexualityrelated distress in Iranian women and can be used to screen patients with HSDD. Azimi Nekoo E, Burri A, Ashrafti F, Fridlund B, Koenig HG, Derogatis LR, and Pakpour AH. Psychometric properties of the Iranian version of the Female Sexual Distress Scale-Revised in women. J Sex Med 2014;11:995–1004. Key Words. Female Sexual Distress Scale-Revised; Iranian Version; Sexually Related Personal Distress; Psychometrics
Introduction
F
emale sexual dysfunction (FSD) refers to the various ways in which a woman is unable to participate in a sexual relationship or experience
© 2014 International Society for Sexual Medicine
sexuality the way she would wish [1]. According to current classification systems, FSD includes disorders of sexual desire, arousal, orgasm, and pain [2]. Prevalences of up to 50% for female sexual complaints have been reported, with estimates difJ Sex Med 2014;11:995–1004
996 fering across populations and cultures [3]. In Iran, epidemiologic studies conducted on women aged between 16 and 71 years have found prevalences of sexual complaints to range from 20% to 50%, depending on the specific sexual problem [4,5]. In addition, a recent study conducted by Ghanbarzadeh et al. found that 39% women (n = 694) reported not feeling any pleasure during their sexual activity and/or during vaginal intercourse [6]. Despite increasing research efforts over the last decades, the current state of knowledge regarding the underlying causes of FSD remains limited [7]. A wealth of cross-national epidemiologic studies have suggested numerous demographic, psychological, and physiological “risk factors” including age, education, mental and physical health, anatomical factors, hormones, genes, etc., thought to be associated with the development and maintenance of FSD [8,9]. However, no clear mechanisms as what causes FSD have emerged yet. In spite of considerable advances in creating conceptual frameworks for FSD, controversies regarding accurate clinical definitions and a uniform classification of FSD exist [10]. According to the Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM-5 criteria) and the American Urological Association Foundation, personal distress is considered one of the key criteria in the diagnoses of FSD [2,11,12]. Accordingly, a woman should show evidence of significant personal distress, characterized by negative feelings and anxiety about one’s sexuality or sexual activities, in relation to her sexual problem to qualify for the diagnosis of FSD. However, quantitative evidence questions the utility of personal sexual distress as a primary diagnostic indicator of FSD, and experts have been unable to reach consensus on whether or not to include distress as a diagnostic key criterion [13–16]. To guarantee an accurate definition of FSD, as well as adequate evaluation and comparability of population-based prevalences, the presence and the degree of distress related to the sexual problem should also be assessed and evaluated when conducting epidemiologic studies on FSD. Generalization of results from epidemiologic studies on FSD to all settings and cultures, especially when based on DSM-derived definitions and diagnostic criteria, is discouraged [17]. Paykel, for example, argued that the DSM is substantially Western based and hence does not consider other syndromes and conditions that influence a woman’s J Sex Med 2014;11:995–1004
Azimi Nekoo et al. sexuality that may be much more prevalent across other cultures [17]. In view of this, the availability of culturally adapted questionnaires that allow the assessment of FSD and sexuality-related distress is crucial. Several tools for the assessment of sexualityrelated distress are now available, such as the Female Sexual Distress Scale (FSDS) [18], the Sexual Desire Relationship Distress Scale [19], and the Decreased Sexual Desire Screener [20]. The most extensively validated and widely used tool for assessing sexuality-related distress in women is the FSDS [21,22]. Recently, a revised version of the FSDS—the FSDS-R—has been developed offering an increased sensitivity–specificity profile of the instrument. The FSDS-R has already been translated into several languages and validated in numerous populations and cultures [21–24]. However, a Persian version of the tool is missing. The purpose of this study, then, was to determine the psychometric properties of the Iranian version of the FSDS-R in a population of Iranian women.
Material and Methods
Sample The study sample consisted of women who had been referred to 10 urban health centers in Qazvin (a city near Tehran) by their general practitioner. A total of 2,400 randomly selected, married, and potentially sexually active women (based on information available from their medical records) were contacted. To participate in the study, women had to be 18 years or older; able to read, speak, and understand Persian/Farsi; married; sexually active; not suffering from any chronic disease (e.g., diabetes mellitus, cardiovascular diseases, hypertension, renal failure, cancer); not taking any antihypertensives, antidepressants, antihistamines, and/or benzodiazepines; not suffering from alcoholism (as assessed by the Alcohol Use Disorders Identification Test) and/or drug and substance abuse; not suffering from depression according to the Hospital Anxiety and Depression Scale (HADS); and not taking any antipsychotic medication. Women using oral contraceptive pill, women with sexual aversion disorder, dyspareunia, vaginismus, gender identity disorder, and/or any paraphilia were excluded from the study. Also excluded were women who were pregnant or 3 months postpartum, undergoing hysterectomy and/or mastectomy, suffering from obesity (body
Female Sexual Distress in Iranian Women mass index [BMI] ≥ 30 kg/m2), or have had a colostomy and/or oophorectomy. Of the 2,400 women contacted, 243 (10.1%) women refused to participate. Of the remaining 2,157, 191 did not meet the inclusion criteria, resulting in a final sample of 1,966 women. Those women agreeing to participate were screened for FSD based on the DSM-IV-TR criteria by two gynecologists. Based on this screening, women were assigned to either the healthy control group or to the FSD case group. Women assigned to the FSD case group were further divided into the hypoactive sexual desire disorder (HSDD) group [25] or the “any other” FSD group. The study protocol was approved by the Ethics Committee of Qazvin University of Medical Sciences, and all women provided written informed consent.
Translation and Cultural Adaptation Procedure The procedure followed to create an Iranian version of the FSDS was equivalent to the one followed for the original English version and suggested by Wild et al., Beaton et al., and Acquadro et al. [26–28]. In the first step, the English version was translated into Persian/Farsi after obtaining permission from the developer of the FSDS-R. Two bilingual translators with Persian/Farsi mother tongue translated the English FSDS into Persian independently from each other. Two other translators, along with the local project manager (A.H. Pakpour), then compared these translations and reconciled them into one Persian/Farsi version. The second step involved a backward translation into English. Two native Englishspeaking translators (bilingual with Persian/Farsi) translated the Persian/Farsi version back into English. These translators were unfamiliar with the original version of the FSDS or its intention or concept. Third, the backward translated versions were then compared with the original English version by the local project manager to ensure that the Persian/Farsi version reflected the same item content as the original English version. In the end, an expert committee including methodologists, biostatisticians, gynecologists, nurses, psychologists, health psychologists, and midwives reviewed the translations, removed any discrepancies, and agreed on a final Persian/Farsi version. Four types of equivalences (semantic, idiomatic, experiential, and conceptual) were considered in this final version. Next, this final Persian/Farsi version was administered to n = 27 women reporting sexual distress (mean age 35 ± 22 years) and to n = 34 healthy women (and not reporting any dis-
997 tress; mean age 37 ± 51 years) to test the conceptual equivalence of the Persian/Farsi version and to assess whether the questionnaire and its items was acceptable, understandable, and appropriate (i.e., cognitive debriefing). A face-to-face interview was performed where respondents were asked to highlight problems in understanding the items and to express their opinions on the item content. Finally, the resulting Persian/Farsi version of the FSDS-R was administrated to the 1,966 women agreeing to participate in the field testing. All of these 1,966 participants were then asked to complete the study tools at three time points: at baseline (after providing written consent), 7 days, and 28 days after baseline assessment.
Measures Socio-Demographic Information Among the socio-demographic characteristics assessed were age, education, husband’s education, duration of marriage, monthly family income, occupation, smoking status, having children, BMI, and duration of menstruation. Standing height was measured without shoes to the closest of 0.5 cm with a calibrated stadiometer, and body weight was measured in light clothes to the closest of 10 g with a calibrated digital scale. BMI was then calculated as weight (kg)/height (m)2. Female Sexual Function Index (FSFI) The Female Sexual Function Index (FSFI) consists of 19 items that cover 6 domains of women’s sexual functioning including sexual desire (2 items), arousal (4 items), lubrication (4 items), orgasm (3 items), satisfaction (3 items), and pain (3 items). All items are scored on a five-point Likert-type scale ranging from 0 (or 1) to 5, with higher scores indicating better sexual functioning [29,30]. FSDS-R The FSDS-R is a self-reported questionnaire consisting of 13 items assessing different aspects of sexual activity-related distress in women [24]. All items are scored on a five-point Likert-type scale ranging from 0 (never) to 4 (always), with higher score indicating more sexual distress. A total score can be computed by adding all 13 item scores [24]. The original version of the FSDS-R demonstrated acceptable scale reliability with Cronbach’s alpha values ranging from α = 0.87 to α = 0.93 and high test–retest reliability (intra-class correlation coefficient ranging from r = 0.74 to r = 0.86) [24]. Furthermore, a unidimensional structure of the J Sex Med 2014;11:995–1004
998 FSDS-R was confirmed by confirmatory factor analysis (CFA) with a cutoff score of ≥11 used to discriminate between women reporting sexual distress and those not reporting any sexuality-related personal distress [23,24].
HADS The HADS is a brief self-report measure used to assess the severity of depressive or anxiety symptoms [31]. The HADS consists of 14 items and two subscales measuring depression (7 items) and anxiety (7 items). Each item is scored on a fourpoint Likert-type scale ranging from 0 to 3, with higher scores indicating more symptoms. A total score for each subscale can be derived by adding up all seven scale items and is categorized as follows: normal (0–7), mild (8–10), moderate (11– 14), and severe (15–21) symptoms of anxiety or depression, respectively. The HADS has been applied extensively across many studies and has been found to be highly reliable and to have excellent validity [32]. The validity and reliability of the Iranian version of the HADS have also been established in a sample of the Iranian patients with breast cancer and been considered excellent [33]. Statistical Analysis To determine the reliability of the FSDS-R, internal consistency and test–retest reliability were assessed. Alpha coefficients (α) were determined as an indicator of internal consistency, while test– retest reliability was estimated using intra-class correlation coefficients (ICCs). An internal consistency of α ≥ 0.70 was considered acceptable [34]. A two-way random effects analysis of variance was performed to examine the test–retest stability of the measure at baseline, after 7 days, and after 28 days. An intra-class correlation coefficient of ≥0.70 was considered acceptable [34]. Convergent validity was examined by computing the inter-correlations between the FSDS total score, the FSFI subscale and total score, and the HADS subscale scores. It was assumed that women with lower sexual functioning suffered from more sexual distress, depression, and anxiety [35,36]. Furthermore, correlation coefficients between the specific questionnaire items and the total score of the FSDS were calculated to assess the construct validity of the FSDS-R. To explore the discriminant validity of the FSDS-R, known-groups comparisons based on their sexual health status (healthy, HSDD, and other types of FSD) were performed among the J Sex Med 2014;11:995–1004
Azimi Nekoo et al. three groups of women. The known-group method tests the ability of the FSDS-R to differentiate between groups with known different sexual health status. It was assumed that women with any type of sexual complaints would report higher FSDS scores compared with healthy women. An analysis of covariance (ANCOVA)—adjusted for age, education, and duration of marriage—was performed to compare the FSDS-R scores between the known groups. In addition to the known-group method, a receiver operating characteristic (ROC) curve was used to determine the optimal cutoff values of the FSDS-R to discriminate between participants with sexual distress (i.e., women with HSDD) and healthy women without sexual distress. The area under curve (AUC), a measure of the degree of information the test contains over its entire score range, was also calculated. An AUC of 0.5 indicates the inability of the measure to discriminate between subgroups of the participants, while an AUC of 1.0 represents perfect discriminant validity [37]. CFA was performed to assess the construct validity of the FSDS-R using LISREL version 8.80 (Scientific Software International, Chicago, IL, USA). Because of the ordinal nature of the data, a weighted least squares with polychoric correlations and asymptotic covariances matrices was used to estimate the model parameters. Three categories of model fit indices were considered to test the fit of the original one-factor model to the data, including absolute fit indices, incremental fit indices, and parsimony fit indices. For the absolute fit indices, the model chi-square (χ2), the root mean square error of approximation (RMSEA), goodness-of-fit statistic (GFI), and standardized root mean square residual (SRMR) were used. The incremental fit indices included the comparative fit index (CFI) and the non-normed fit index (NNFI, also known as the Tucker–Lewis index). Finally, the parsimonious normed fit index (PNFI) was also assessed. An RMSEA value
