[Validation of an HIV and other sexually transmitted infections knowledge scale in an adolescent population]

The objective of this research is to determine the validity and reliability of a questionnaire designed to specifically assess the knowledge of HIV and other sexually transmitted infections in a Spanish adolescent population.

Cross-sectional study for the validation of a questionnaire.

A total of 17 schools in five Spanish provinces.

A total of 1,570 adolescent schoolchildren between 13 and 17 years old.

A pool of 40 items relating to knowledge about HIV and other sexually transmitted infections was established. This pool was analyzed by an expert panel. It was then administered to a pilot group with the same demographic characteristics of the sample, to ensure comprehension.

Item analysis, internal consistency, test/retest and exploratory factorial analysis.

A factor analysis was performed, in which five factors that explained 46% of the total variance were retained: general knowledge about HIV, condom as a protective method, routes of HIV transmission, the prevention of HIV, and other sexually transmitted infections. Reliability measures ranged from 0.66 to 0.88. The test-retest correlation was 0.59. There were gender differences in the knowledge of infections.

These factors have adequate internal consistency and acceptable test-retest correlation. Theoretically, these factors fit properly with the content of the items. The factors have a moderate relationship, indicating that a high degree of knowledge about an aspect, but not a guarantee of general knowledge. The availability of a questionnaire to assess knowledge of sexually transmitted infections is helpful to evaluate prevention programs.