Validation of questionnaire estimating predictors of behavior intention to engage in first sexual intercourse among eighth-grade pupils.

AIM To use structural equation modeling in testing the construct validity of the questionnaire on the first sexual intercourse among young adolescents. METHODS Previously created questionnaire for the estimation of different factors influencing the intention to engage in the first sexual intercourse was validated. The data were gathered anonymously from a nationally representative sample of 1217 elementary school pupils aged 14-15 in Slovenia. The construct validity was determined by the structural equation modeling, LISREL 8.7. RESULTS The reliability of the questionnaire was satisfactory (Cronbach alpha=0.73). Using the structural equation modeling analyses, the fit between empirical and theoretical models was confirmed, with 18 variables (17 independent and 1 dependent) for 6 latent indicators (5 external and 1 internal). The measures of goodness of fit were chi2(80)=57.040; P=0.976; the root mean square error of approximation was <0.001; the root mean square residual was 0.0249; the goodness of fit index was 0.994; the adjusted goodness of fit index was 0.988; the normed fit index was 0.993; and the relative fit index was 0.986. The instrument explained 34% of the variance in behavior intention. CONCLUSION The construct validity of the questionnaire on the intention to engage in the first sexual intercourse among young adolescents was satisfactory. This questionnaire could be a useful tool in health promotion programs.