Sexual distress is defined as the subjective distress associated with sexual functioning and constitutes an essential criterion for the diagnosis of sexual dysfunctions in current classification systems (1). This criterion makes it possible to differentiate between normal variations in sexual response and disturbances of clinical relevance, since the mere presence of sexual difficulties is insufficient to establish a diagnosis unless accompanied by clinically significant distress. In recent literature, sexual distress has been described as a multidimensional phenomenon encompassing psychological, relational, and cultural components (2).

Processes such as mindfulness, acceptance, and experiential avoidance have been documented to influence its manifestation (3,4), whereas other approaches link it to the discrepancy between actual sexual experiences and expectations shaped by cultural scripts (5). These contributions have consolidated sexual distress as a complex construct that integrates cognitive, emotional, and contextual factors, thereby justifying its assessment within a comprehensive biopsychosocial model. In this regard, the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), emphasizes the central role of sexual distress, underscoring its usefulness in differentiating sexual dysfunctions from transient problems or non-pathological variants of sexual behavior (6-8).

Sexual distress has relevant clinical and psychosocial implications, as it is associated with impaired mental health, lower satisfaction in interpersonal relationships, and reduced quality of life. Its expression results from the interaction between individual factors, such as genital function, and contextual elements, including partner dynamics and social attitudes toward sexuality (9,10). Nevertheless, its assessment represents a clinical challenge, since the presence of sexual dysfunction is not always accompanied by subjective distress; for example, some men with premature ejaculation do not report significant emotional impairment (6). Additional barriers, such as stigma, costs, and lack of time, may inhibit the seeking of professional care, even when sexual well-being is compromised (9,10).

Although sexual distress has been widely recognized as a key diagnostic component, the development of standardized psychometric instruments has focused almost exclusively on women. The Female Sexual Distress Scale (FSDS), developed by Derogatis et al. (11), has become the reference instrument for measuring sexual distress in women, owing to its excellent psychometric properties and cross-cultural adaptations in different contexts (12). In recent years, important efforts have emerged to validate versions of this scale in male populations across different international settings (13,14), demonstrating the feasibility and relevance of adapting this instrument for men. However, in the Mexican context, a significant gap remains in the assessment of male sexual health, as to date there is no equivalent, robust, and culturally adapted instrument to specifically quantify sexual distress in Mexican men. This absence limits professionals’ ability to diagnose the condition accurately and determine the severity of the problem in this population.

Since its original validation, the FSDS has demonstrated strong internal consistency, with Cronbach’s alpha coefficients ranging from 0.86 to 0.93, as well as a unidimensional structure supported by factor analysis (11). Subsequently, several cross-cultural adaptations have confirmed its psychometric robustness, including the Spanish version, which reported high reliability (α = 0.90), adequate construct validity, and invariance across groups (13). International studies have also shown its clinical utility both in women with sexual dysfunction and in the general population, with reliability coefficients above 0.85 and adequate factorial fit indices (14-16). Taken together, this evidence supports the relevance of developing an adapted version for the male population.

The cross-cultural adaptation of the FSDS for the male population responds to the need for conceptually equivalent and culturally appropriate instruments that validly assess the construct across different contexts. This process is supported by widely accepted frameworks on linguistic equivalence and measurement validity, in accordance with the Standards for Educational and Psychological Testing (17-19). Adapting an instrument with strong psychometric support and a well-established factorial structure is methodologically more advantageous than developing a new scale, as it allows researchers to build on a robust theoretical foundation, facilitates international comparability, and optimizes resources; likewise, this strategy addresses the lack of instruments specifically designed for men. In view of this gap, the present study aimed to adapt and validate the FSDS for use in the Mexican male population, thereby giving rise to the Male Sexual Distress Scale (Escala de Malestar Sexual Masculino, EMSM).

A cross-sectional methodological study was conducted to evaluate the measurement properties of the EMSM, following the guidelines of the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN guideline) (20). Instrumental studies fall within methodological designs aimed at developing or adapting tools that allow psychological and behavioral variables to be measured accurately in specific contexts (21,22). The study was conducted in three phases: 1) content validation, 2) evaluation of psychometric properties, and 3) establishment of reference values (23).

The sample consisted of 310 Mexican men, aged between 18 and 25 years (M = 20.3; SD = 2.2), who were university students and sexually active. Recruitment was performed through two-stage probability cluster sampling. In the first stage, 15 academic groups (primary sampling units) were randomly selected from a total of 45, belonging to the faculties of engineering, architecture, and computer science at a Mexican public university. In the second stage, all sexually active male students who were part of the selected clusters and met the eligibility criteria were included: being of legal age, having proficiency in the Spanish language, not having a current diagnosis of a psychotic disorder or significant cognitive impairment, and not having previously participated in similar studies in order to avoid reactivity bias (Table 1).

Table 1. Table 1. Sociodemographic characteristics f:

frequency

The sample size (n = 310) meets the commonly accepted criteria for the validation of psychometric instruments. Following the recommendation of having at least 10 observations per item (310 > 130 for a 13-item scale) (24), the stability of the parametric estimates is ensured. Additionally, to assess sample adequacy in the context of confirmatory factor analysis (CFA), a post hoc sensitivity analysis was performed using the semPower package in R. Considering the degrees of freedom of the final model (df = 53), the Root Mean Square Error of Approximation (RMSEA) value obtained in the CFA (ε = 0.026) as an estimate of the effect size in the population, and a significance level of α = 0.05, the observed statistical power was greater than 0.99. This value substantially exceeds the conventional threshold of 0.80 recommended for testing the hypothesis of lack of fit, namely the test of close fit, in structural equation models (25). Consequently, it is confirmed that the study had the necessary statistical power to support the validity of the unidimensional structure of the EMSM, minimizing the probability of type II error (Table 2).

Table 2. Table 2. Comparison of model fit indices for the Male Sexual Distress Scale

AGFI: Adjusted Goodness of Fit; CFI: Comparative Fit Index; GFI: Goodness of Fit Index; df: degrees of freedom; χ^²/df: chi-square-to-degrees-of-freedom ratio; RMSEA: Root Mean Square Error of Approximation; TLI: Tucker-Lewis Index; EMSM: Male Sexual Distress Scale.

The study used an adapted version of the FSDS (11), a 12-item self-report questionnaire with a Likert-type response format ranging from 0 (never) to 4 (always). The total score, obtained by summing the items, reflects the level of sexual distress, with higher scores indicating greater impairment. Although originally developed for women, a semantic adaptation was used for male university students to ensure conceptual equivalence. The instrument was administered digitally in a self-administered format. Regarding its metric properties, the FSDS has demonstrated high reliability, with alpha coefficients ranging from 0.86 to 0.97 and adequate temporal stability values (r = 0.80-0.92), supporting its internal consistency and reproducibility. It also shows strong validity, evidenced by a stable unidimensional model and convergent validity with clinical indicators of sexual dysfunction.

The study followed a structured psychometric validation process in three phases, aligned with recognized methodological guidelines for the cross-cultural adaptation of instruments, including translation-back-translation, semantic equivalence analysis, and evaluation of psychometric properties in the target population, as well as with the Standards for Educational and Psychological Testing. First, formal authorization was obtained from the participating educational institution, along with approval from the corresponding Research Ethics Committee (registration number ICSa/280/2024). Subsequently, the cultural adaptation of the EMSM was carried out through the independent evaluation of a panel of ten experts in sexuality, psychometrics, and methodology, who assessed the pertinence, clarity, and cultural relevance of the items using a four-point scale. Based on the item-level validity indices and qualitative observations, the necessary semantic adjustments were incorporated to ensure the conceptual coherence and cultural appropriateness of the instrument.

In the second phase, a pilot test was conducted with male university students recruited through direct invitation in classrooms authorized by the institution. The pilot test was administered in a controlled environment within the academic facilities, under the supervision of the research team and using standardized instructions. After administration, feedback was obtained regarding the comprehension of the items, which allowed the wording of some items to be adjusted.

In the third phase, the final administration of the instrument was conducted with the total study sample. Participants were recruited through cluster sampling from previously selected and authorized academic groups. The scale was administered electronically in a controlled classroom, with in-person supervision by the research team, to ensure homogeneous administration conditions, privacy, and adequate understanding of the instructions. Participation was voluntary, anonymous, and preceded by the signing of informed consent.

Data were analyzed according to international standards for instrument validation (20). In the first stage, content validity was assessed using the Item-Level Content Validity Index (I-CVI), calculated from the ratings provided by a panel of 10 experts using a four-point scale (1 = not pertinent at all to 4 = highly pertinent) (26). Each item was considered adequate when it reached an I-CVI equal to or greater than 0.78, following the criteria proposed by Mary Lynn (27) for instruments evaluated by more than 6 judges.

Construct validity was subsequently examined through confirmatory factor analysis (CFA), using structural equation models with estimation for ordinal variables (28). To determine the adequacy of the factorial model, the fit indices recommended in the psychometric literature were used: a Comparative Fit Index (CFI) greater than 0.90, a Tucker-Lewis Index (TLI) greater than 0.90, and an RMSEA below 0.08 (28,29). Based on these criteria, different model specifications were evaluated, also considering modification indices to identify potential residual correlations or adjustments to the theoretical structure (30,31).

The internal reliability of the scale was determined using Cronbach’s alpha coefficient and McDonald’s omega coefficient. In both cases, a minimum value of 0.70 was used as the acceptability criterion, corresponding to the standard for psychological and health sciences instruments (31,32).

As part of the precision analysis, the standard error of measurement (SEM) was estimated using the formula SEM = SD × √(1 − α), and the minimum detectable difference (MDD) was determined using the parameter MDD = 1.96 × √2 × SEM, in accordance with guidelines for interpreting random error in measurement instruments. Prior to the main analysis, missing data patterns were reviewed, and when the proportion of incomplete data was below 5%, multiple imputation was applied following recommendations to minimize bias and preserve data variability (33). All statistical procedures were performed using Jamovi, version 2.7.6, with the lavaan, psych, and ltm modules (34), in accordance with the criteria established by the COSMIN guideline for the interpretation and reporting of measurement properties.

The results obtained support the robustness of the EMSM adaptation process, particularly with regard to content validity. The high level of agreement among experts suggests that the items are pertinent, clear, and culturally appropriate, which is consistent with international recommendations emphasizing the preservation of conceptual equivalence over literal translation (17,18). Expert review made it possible to identify and adjust potential semantic ambiguities that could lead to interpretations influenced by moral, medical, or identity-related norms, a relevant aspect in the assessment of male sexuality.

Regarding internal structure, the CFA results support a unidimensional model of male sexual distress, consistent with the original validation of the FSDS (11) and with previous adaptations in different cultural contexts (13,16). However, in the validation conducted with Colombian and Canadian male populations, no items were removed and the original version was retained (13). The confirmation of this structure in a male population reinforces the notion that sexual distress can be conceptualized as a global construct that integrates emotional experiences, such as distress, frustration, and concern associated with sexual life, regardless of gender.

The original scale consisted of 13 items; however, in this study it was reduced to 12 through the removal of item four (“Have you felt frustrated by your sexual problems?”). From a theoretical perspective, frustration associated with sexual problems has been documented mainly in contexts of sexual dysfunction linked to chronic conditions, such as erectile dysfunction and other health-related alterations, primarily in middle-aged and older adults (35,36). In this regard, its conceptual relevance in a university population appears limited, given that in this age group the presence of sexual problems is usually lower and less frequently associated with established clinical conditions (37,38).

Additionally, the content of the item showed overlap with other indicators of emotional distress related to stress and concern, suggesting conceptual redundancy within the construct evaluated. In accordance with principles of instrument development, it is recommended to prioritize parsimony and the theoretical representativeness of items, while avoiding the overrepresentation of similar dimensions (26,27). Although the item was considered relevant by experts during the content validity phase, its removal from the final model is justified by its limited theoretical adequacy for the study group and by its contribution to a better specification of the construct in this population, which was also reflected in improved model fit indices.

Likewise, the high factor loadings indicate a strong relationship between the items and the latent construct of sexual distress, particularly in items related to emotional distress, frustration, and negative perceptions of sexual performance. This pattern is consistent with literature indicating that sexual distress does not depend exclusively on genital function, but is deeply influenced by the subjective and affective interpretation of the sexual experience (11,39). In this sense, the findings reinforce the importance of emotional components as the core of male sexual distress (4,7,10).

In terms of reliability, the EMSM showed high levels of internal consistency, comparable to those reported for the original scale and its cross-cultural adaptations (31,32), suggesting that the measurement of sexual distress maintains its internal stability even when applied to a population different from the one originally studied. In addition, the estimation of the standard error of measurement and the minimum detectable difference provides useful information for the clinical interpretation of scores, as it allows discrimination between real changes and variations attributable to measurement error.

As implications for practice, the EMSM is a reliable and validated instrument for the Mexican population and can be used by health professionals to identify sexual distress that may lead to future sexual health problems, particularly in vulnerable populations. As a brief scale, it will facilitate administration in clinical and community settings and may serve as a guide for identifying the effectiveness of treatments in individuals with sexual health problems. In research settings, it could be used to evaluate the effectiveness of interventions aimed at identifying improvements in sexual health.

Finally, some study limitations should be considered. The sample consisted exclusively of young male university students, which limits the generalizability of the results to other stages of the life cycle, gender identities, and diverse sociocultural contexts. Likewise, the cross-sectional design prevented the assessment of the instrument’s temporal stability; therefore, future research should incorporate test-retest reliability analyses and explore additional evidence of validity, such as convergent and discriminant validity. Despite these limitations, the results provide relevant evidence regarding the validity and reliability of the EMSM and lay the groundwork for its use in research and clinical practice. Future studies are recommended to include women and to differentiate among individuals from the LGBTQ+ community in order to identify whether invariance exists within the population. Likewise, validations should be conducted in other age groups, such as middle-aged and older adults, using the initial 13 items of the scale.

In conclusion, the EMSM showed adequate psychometric properties for the assessment of sexual distress in men, with solid evidence of content validity, structural validity, and high reliability. The confirmation of a unidimensional structure supports the conceptualization of sexual distress as a global construct centered on subjective experience, beyond sexual functioning. These findings support the use of the EMSM as a valid and reliable tool for research and clinical practice, particularly in contexts where instruments specific to the male population are lacking. Nevertheless, future studies are recommended to expand the evidence of validity and evaluate its temporal stability in more diverse populations.