RESUMEN
OBJECTIVE: Determining HIV/AIDS prevalence in Medellin, Colombia, and its association with demographic factors2006-2012,as well as exploring screening test performance. METHODS: This was a cross-sectional study involving 5,851subjects. Descriptive statistics were used to describe the population (i.e. frequencies and summary measures); infection prevalence was calculated and its association with demographic factors identified by using parametric and non-parametric statistical tests, prevalence ratios and odds ratios. Predictive values were calculated, as were the percentage of false results and percentage of subjects correctly diagnosed. RESULTS: Mean age was 27 years old (0 to 94 year range); 70.5% of the population were female. HIV/AIDS prevalence was found to be 1.8% during the study period (0.32% annually). A statistical association was found with gender and age, a higher prevalence being found in males and adults. The false positive rate was 0.7%, negative predictive value100%, positive predictive value 71% and there was 99% overall efficiency. CONCLUSION: HIV/AIDS prevalence found in this study was significantly higher than that found in other studies in the Antioquia department and for Colombia overall. The male and female infection prevalence ratio revealed increased diagnosis in women. The screening test performed well in areas having less than 1% infection prevalence.