Purpose: Public health officials promote sexually transmitted infection (STI) testing as a method to reduce the morbidity of STIs. The purpose of this study was to examine what factors are associated with STI testing among young women across various types of STIs and to compare relative influences of factors across models. Methods: A secondary data analysis of data from Add Health Wave III was conducted ( n=2629). Explanatory factors highlighted in qualitative literature were operationalized and built into a logistic regression model used to predict testing for chlamydia, gonorrhea, syphilis, human papillomavirus (HPV), genital herpes, and HIV. Results: STI symptoms and concerns about a recent sexual encounter were important expressed reasons for seeking medical care. Number of sexual partners, sexual orientation, STI symptoms, and going to the gynecologist in the past 12 months were important predictors of testing across STIs. This study supports qualitative work that suggests preventive health consciousness, STI symptoms, and relationship characteristics are important factors in STI testing. Results question the validity of self-report data regarding STI testing. Conclusions: Education efforts in secondary school health programs and during gynecologic examinations can decrease confusion about STI testing. [ABSTRACT FROM AUTHOR]