Colposcopy referral rates post-introduction of primary screening with human papillomavirus testing - evidence from a large British Columbia cohort study

Sep 24, 2026

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Shifting from cytology to human papillomavirus (HPV)-based cervical cancer screening is expected to raise initial colposcopy referrals, but long-term persistence remains uncertain. This study analyzes HPV for Cervical Cancer Screening trial participants followed 10–14 years and compares them with a British Columbia screening cohort. After initial rounds, post-trial referral rates decrease significantly, approaching cytology program levels within 11–12 years, supporting staged implementation to mitigate system burden.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages11

Reading Time28 min

AccessFree to download

Summary

Background

Methods

Study design and cohorts

Referral scenarios and outcomes

Statistical analysis

Findings

Interpretation

Funding

Research in context

Evidence before this study

Articles Colposcopy referral rates post-introduction of primary screening with human papillomavirus testing: evidence from a large British Columbia cohort study Anna Gottschlich,a,b,c,∗ Lovedeep Gondara,d Laurie W. Smith,a,e Jennifer Joy Anderson,a,f Darrel Cook,g Mel Krajden,f,h Marette Lee,d Ruth Elwood Martin,f Joy Melnikow,i Stuart Peacock,e,j,k Lily Proctor,a,e,f Gavin Stuart,f Eduardo L. Franco,l Dirk vanNiekerk,d,f and GinaS. Ogilviea,f,g aWomen’s Health Research Institute, BC Women’s Hospital and Health Service, Vancouver, BC, Canada bWayne State University, School of Medicine Departments of Oncology, Detroit, MI, USA cBarbara Ann Karmanos Cancer Institute, Detroit, MI, USA dCervical Cancer Screening Program, British Columbia Cancer Agency, Vancouver, BC, Canada eCancer Control Research, British Columbia Cancer Agency, Vancouver, BC, Canada fFaculty of Medicine, University of British Columbia, Vancouver, BC, Canada gBritish Columbia Centre for Disease Control, Vancouver, BC, Canada hLower Mainland Laboratories, Vancouver, BC, Canada iCenter for Healthcare Policy and Research, University of California Davis, Sacramento, CA, USA jCanadian Centre for Applied Research in Cancer Control (ARCC), Vancouver, BC, Canada kFaculty of Health Sciences, Simon Fraser University, Vancouver, BC, Canada lDivision of Cancer Epidemiology, McGill University, Montreal, Quebec, Canada Summary Background Shifting from cytology to human papillomavirus (HPV)-based cervical cancer screening will initially increase colposcopy referrals. The anticipated impact on health systems has been raised as a concern for implementation. It is unclear if the higher rate of colposcopy referrals is sustained after initial HPV-based screens or reverts to new lower baselines due to earlier detection and treatment of precancer. This study aimed to investigate long-term rates of colposcopy referrals after participation in HPV-based screening. Methods Participants of HPV for Cervical Cancer Screening trial (HPV FOCAL) received one (HPV1, N = 6204) or two (HPV2, N = 9540) HPV-based screens. After exit, they returned to British Columbia’s (BC) cytology screening program. A comparison cohort from the BC screening population (BCS, N = 1,140,745) was identiﬁed, mirroring trial inclusion criteria. All participants were followed for 10–14 years through the provincial screening registry. Colposcopy referral rates per 1000 screens were calculated for each group. Trial colposcopy referrals for HPV1 and HPV2 were calculated under two referral scenarios: (1) all HPV positive referred to colposcopy; (2) cytology triage with ASCUS or greater referred to colposcopy. Colposcopy referrals from post-trial screens in HPV1 an HPV2 and all screens in BCS were based on actual recommendations from the screening program. A multivariable ﬂexible survival regression model compared hazard ratios (HR) throughout follow-up. Findings Scenario 2 referral rates were higher during initial HPV screen(s) vs cytology screen (HPV1: 28 per 1000 screens (95% CI: 24, 33), HPV2: 32 per 1000 screens (95% CI: 29, 36), BCS: 8 per 1000 screens (95% CI: 8.9)) . However, post-trial rates in HPV1 and HPV2 were signiﬁcantly lower than in BCS. Cumulative rates in HPV1 and HPV2 approached the cumulative rate in BCS 11–12 years after HPV-based screening (HPV1: 11 per 1000 screens (95% CI: 10, 12), HPV2: 16 per 1000 screens (95% CI: 15–17), BCS: 11 per 1000 screens (95% CI: 10, 11)) . Adjusted models demonstrated reductions in referral rates in HPV1 (HR = 0.6, 95% CI: 0.5, 0.7) and HPV2 (HR = 0.7, 95% CI: 0.6, 0.8) relative to BCS by 54 and 72 months post-ﬁnal HPV screen respectively. Interpretation Reduced colposcopy referral rates were observed after initial rounds of HPV-based screening. After initial HPV screening, referral rates to colposcopy after cytology triage were below the current rates seen in a centralized cytology program after approximately four years. Any expected increase

FAQs

Why are colposcopy referral rates expected to change after switching to HPV-based screening?

HPV-based screening is more sensitive than cytology, so the initial HPV round can increase referrals to colposcopy. The main concern is whether that higher referral level persists or returns to lower baselines later.

How were colposcopy referral rates calculated in the study?

Referral rates per 1000 screens were computed for HPV trial participants and a comparison cohort. Two referral scenarios were used for HPV-positive results: (1) all HPV positive referred, or (2) cytology triage with ASCUS or greater referred.

What did the study find about long-term referral rates after the initial HPV rounds?

Post-trial colposcopy referral rates after cytology triage were significantly lower than in the British Columbia cytology cohort. Cumulative rates approached the cytology baseline about 11–12 years after HPV-based screening, with adjusted models showing reduced hazards.

Sep 24, 2026

Uploaded by Pentious