The benefits and harms of cancer screening programmes for adults with intellectual disabilities: A systematic review

BACKGROUND: Cancer screening programmes are an important public health initiative aimed at reducing morbidity and mortality through early cancer detection. The available evidence suggests lower screening uptake among people with intellectual disabilities, but the balance of benefits and harms of screening is unknown. The aim of this systematic review is to examine the health outcomes (mortality, morbidity) and harms of cancer screening programmes for adults with intellectual disabilities. METHODS: The review is registered on the Open Science Framework Registries: https://osf.io/8vmkb. A systematic search of published peer-reviewed and grey literature was conducted from inception up to 28th February 2025 using MEDLINE, EMBASE, Web of Science, PsycINFO, and relevant organisational websites. Experts were also consulted about evidence on the benefits and harms of cancer screening programmes for adults with intellectual disabilities. Two reviewers independently screened titles and abstracts and assessed full texts against the eligibility criteria. RESULTS: 3104 records were identified, and 232 full-text articles were assessed for eligibility. No study met the inclusion criteria. POLICY SUMMARY: There is a lack of evidence on the benefits and harms of cancer screening programmes for people with intellectual disabilities. There are numerous studies relating to coverage, uptake, and factors influencing participation in cancer screening programmes. Participation should not be assumed to equate to better outcomes, and there is a risk of 'equity-washing' if this is used as a basis for practice. There is an urgent need to evaluate the entire screening pathway for people with intellectual disabilities, for the associated outcomes, benefits, and harms.