Colposcopic assessment by Swedescore, evaluation of effectiveness in the Swedish screening programme: a cross-sectional study

Abstract

Objective: To evaluate the effectiveness and performance of Swedescore in the Swedish screening programme. Design: Cross-sectional register study. Setting and Population: All Swedish women aged over 18 years with a colposcopic assessment linked to a biopsy in the Swedish National Cervical Screening Registry, 2015–20. Methods: Colposcopies with Swedescore were compared with the histopathological diagnosis of cervical intraepithelial neoplasia grade 2 or higher (CIN2+). The respective influence of cytology and human papillomavirus (HPV) testing, at referral for colposcopy and concurrently with colposcopy, were investigated in regression models. Main Outcome Measures: CIN2+. Results: A total of 11 317 colposcopic assessments with Swedescore were included. Odds ratios for CIN2+ increased for every step in the Swedescore scale. At Swedescore ≥0–1, the proportion of CIN2+ was 9.8%. At Swedescore ≥8, the specificity was 93.3% and the positive predictive value was 60.1%, Area under the receiver operating characteristics curve (AUC) was 0.71. If the smear had been abnormal at referral, a normal colposcopy (Swedescore 0–1) was still associated with a CIN2+ risk of more than 5%. In the regression model, cytology and HPV had higher odds ratio for CIN2+ than colposcopy; the combination resulted in an AUC of 0.88. Conclusions: Swedescore works well in a routine clinical setting but colposcopy assessed with Swedescore was inferior to that reported in previous clinical studies. No safe cutoff level was identified for refraining from biopsy. See-and-treat at Swedescore 8–10 is feasible only if referral cytology showed high-grade squamous intraepithelial lesion. Tweetable Abstract: No safe cutoff level for refraining from biopsy nor for see-and-treat with Swedescore.