Incomplete follow-up of positive HPV tests: overview of randomised controlled trials on primary cervical screening

BACKGROUND: It has been suggested that adjustment for incomplete compliance with follow-up in women with positive human papillomavirus (HPV) tests would be appropriate for estimating the true sensitivity of cervical screening with HPV testing. We assessed the compliance and its impact on ⩾CIN3 detection in all eight randomised controlled trials (RCT) with published baseline-round data. METHODS: We extracted data on recommended follow-up procedures, follow-up compliance, and ⩾CIN3 detection for both arms of each RCT, and assessed their correlation. RESULTS: Compliance with a direct referral for colposcopy was around 90% in all RCTs, whereas compliance with repeated testing among HPV-positive/cytology-negative women was around 60% in three RCTs and 73% in one RCT. Detection of ⩾CIN3 was significantly increased in two out of six RCTs with reported data. The correlation between compliance with follow-up in HPV-positive women and relative ⩾CIN3 detection was 0.48 (P=0.33). CONCLUSION: There is at present scant evidence to support the view that the measured sensitivity of HPV screening is a simple reflection of compliance with follow-up. Adjustment of measured cervical intraepithelial neoplasia detection on the basis of compliance data may not always be justifiable, and if adjustment is made, it should be used very judiciously.