Adherence patterns to extended cervical screening intervals in women undergoing human papillomavirus (HPV) and cytology cotesting

Although guidelines have recommended extended interval cervical screening using concurrent human papillomavirus (HPV) and cytology (“cotesting”) for over a decade, little is known about its adoption into routine care. Using longitudinal medical record data (2003–2015) from Kaiser Permanente Northern California (KPNC), which adopted triennial cotesting in 2003, we examined adherence to extended interval screening. We analyzed predictors of screening intervals among 491,588 women undergoing routine screening, categorizing interval length into early (