Investigating the structural validity and reliability of the sexual health literacy for adults (SHELA) questionnaire among a sample of women in Qazvin, Iran

Background The correct measurement of sexual health literacy requires an instrument with desirable psychometric properties and fitness to the sociocultural context. Despite acceptable psychometric properties of the sexual health literacy for adults questionnaire in the mixed population of men and women, the validity and reliability of this questionnaire in the female population were not determined. Therefore, considering differences in the study population, this study aimed to determine the structural validity and reliability of the questionnaire among women. Methods The present study was a methodological and psychometric study of instruments conducted among 310 women referring to healthcare centers in Qazvin, Iran in 2020. Sampling was done using a one-step cluster method. We used Cronbach's alpha coefficient, Pearson correlation coefficient, and confirmatory and exploratory factor analyses to determine the reliability, convergence validity, and construct validity of the questionnaire respectively. Also, the Sexual Quality of Life-Female questionnaire (SQOL-F) and the Female Sexual Function Index (FSFI) were used to evaluate the convergence validity. Data were analyzed using SPSS 20, and STATA 13. Results Exploratory factor analysis identified three factors including, “reading and understanding”, “evaluation and application of information”, and “skills of access” which together accounted for 70.85% of the whole variance. Based on the results of confirmatory factor analysis, this questionnaire had overall goodness of fit too. (RMSEA = 0.071, CFI = 0.928, TLI = 0.919, SRMR = 0.041, X2/df = 2.501). Convergent validity of the questionnaire showed a correlation of 0.121–0.243 between the questionnaire's dimensions with the FSFI and the SQOL-F questionnaires respectively. Also, the results showed that the questionnaire had proper internal consistency (Cronbach’s alpha was 0.981) for measuring sexual health literacy in women. Conclusions The 39-item sexual health literacy assessment questionnaire consisting of 3 factors in the present study was endowed with sufficient validity and reliability, and it can be used for precisely assessing women’s sexual health literacy.