Closing the cervical screening cascade gap toward WHO 90-70-90 elimination targets: A systematic review and meta-analysis of 25 studies in 11 countries

Abstract

The WHO 90-70-90 cervical cancer elimination targets require that 90% of women with screen-detected lesions receive appropriate treatment by 2030. Achieving this target depends on closing cascade gaps from screen-positive to diagnostic resolution. Whether intervention effectiveness varies by delivery modality or by cascade-step position remains unresolved, with implications for resource allocation in low- and middle-income countries that bear most of the elimination gap. We searched PubMed, Embase, CINAHL, and Cochrane Library from inception through 31 March 2026 (PROSPERO CRD420251031531; PRISMA 2020). Hartung–Knapp–Sidik–Jonkman random-effects models were primary. Subgroup analyses examined design, intervention type, country income, digital component, and (exploratory) cascade-step position. Publication bias was assessed by Egger’s, trim-and-fill, and PET-PEESE methods; GRADE was applied. Of 33 included studies, 25 (N = 142,298 across 11 countries, 6 continents) entered the primary meta-analysis. Interventions were associated with higher odds of follow-up completion (HKSJ OR = 2.03; CI 1.71–2.41; I² = 83.1%; prediction interval 1.11–3.73). Effects were directionally consistent across study designs (subgroup ORs 1.80–2.21). Substantial publication bias was present (Egger P < 0.001); bias-adjusted estimates attenuated to OR = 1.73–1.88, and the low/moderate-bias subset (k = 15) yielded OR = 1.87 (1.55–2.26). Subgroup differences by intervention type, digital component, and country income were not significant (all P > 0.25). In contrast, effects differed by cascade-step position (P = 0.006): largest for colposcopy attendance (OR = 2.35) and smallest for diagnostic resolution (OR = 1.46). GRADE certainty was very low overall. Structured interventions were associated with increased follow-up completion across all delivery modalities tested, with bias-adjusted OR of about 1.8 (an absolute gain of about 14 percentage points at a 30% baseline rate). In exploratory analyses, effect-size variation was associated more with cascade-step position than with intervention type, with effects appearing to diminish along the screening cascade; single-point interventions may therefore not navigate the full diagnostic pathway alone. Reaching the WHO 90% treatment target requires layered, step-specific interventions, prioritizing distal cascade steps and randomized evidence from low- and middle-income settings. PROSPERO CRD420251031531 (registered prior to data extraction; literature search had commenced before registration was finalized).