Estimated 2 and 5 Year Transition Probabilities (95% C.I) for Progression and Regression in 3-State Hidden Markov Model Adjusted for Cytology Misclassification Assumptions, by IAC-Exclusion Window (≤180 vs.≤30 days)1.

1.Model estimates fit with time-updated infrared coagulation (IRC) indicator and standardized to reflect transition probabilities for those who never underwent IRC. Thus, these transition probabilities estimate the untreated natural history of AIN.2.IAC exclusion window: Cases of invasive anal carcinoma (IAC) diagnosed within 180 or 30 days of the first cytology result, respectively, were considered prevalent cases and were therefore excluded from analysis.3.Transition from HSIL: HSIL: high grade squamous intraepithelial lesion; IAC: invasive anal carcinoma.