A comparison of survey techniques on sensitive sexual behavior in Italy

This article compares two national surveys carried out through the most commonly used procedures in Italy: CATI (computer-assisted telephone interviews) and SAQ-FI (self-answered questionnaires following interviews). Both surveys ask two identical questions concerning sensitive sexual behavior: early age at first intercourse and same-sex attraction. The SAQ-FI survey had both unit non-response and item non-response rates much lower than the CATI survey. Moreover, in the CATI survey, the groups with highest item non-response rates were also the groups with the lowest proportions of early intercourse and homosexual attraction. In addition, a differential analysis of the respondents produced diverse results for the two surveys. This is especially true of results by gender for same-sex attraction: Such behavior is more common among men (3.1%) than women (2.9%), according to the CATI survey, whereas the opposite is true of the SAQ-FI survey (6.1% of men vs. 7.7% women). In Italy at the beginning of the 21st century, CATI surveys reveal a lower level of early intercourse and same-sex attraction than SAQ-FI surveys. This article argues that the CATI survey underestimates the true level of these sensitive sexual behaviors in the Italian population.