Association between sexual factors and abnormal anal cytology among study participants.

Abbreviation: ASCUS = atypical squamous cells of undetermined significance; ASC-H = atypical squamous cells but cannot exclude HSIL; ASIL = anal squamous intraepithelial lesions, include low-grade squamous intraepithelial lesion (LSIL) and high-grade squamous intraepithelial lesion (HSIL).*Sum may not always add up to total because of missing data.#Syphilis positivity was determined through screening by a positive rapid-plasma reagin test and confirmation by an Enzyme-linked immunosorbent assay for detection of antibodies to Treponema pallidum.