The impact paradox: mixed-methods evaluation of National Institute of Health and Care Research funding for intellectual disability research in the UK

BACKGROUND: People with intellectual disability experience substantial health inequities, including higher multimorbidity, increased healthcare utilisation and markedly reduced life expectancy. High-quality research is essential to address these disparities. The National Institute for Health and Care Research (NIHR) funded Research Delivery Network provides the infrastructure/expertise/support needed to deliver NIHR-funded studies, and supports studies funded by a non-commercial/industry partner. However, the effectiveness of NIHR-funded studies versus those supported in driving impactful intellectual disability research remains unclear. AIMS: To evaluate and compare the outcomes of NIHR-funded and supported intellectual disability research. METHOD: All NIHR studies (funded/supported) relating to intellectual disability (2010-2020) were identified through systematic register searches. Primary outcomes included publication rates and impact on local, national and international clinical guidelines. Data collection was supplemented with a questionnaire to chief investigators and literature searches. Quantitative analyses examined associations between funding status, study design, publication and guideline impact, whereas qualitative responses explored implementation challenges. RESULTS: In total, 88 projects were identified, and 42% (37/88) were NIHR-funded. Overall, 81% of studies generated at least one publication and 28% informed clinical guidelines. NIHR funding was not significantly associated with publication or guideline impact. Randomised controlled trials (RCTs) were significantly more likely to be published and more likely to influence non-UK national and international guidelines than non-RCTs. The amount of funding showed no association with impact. Qualitative findings highlighted funding constraints, staff capacity and stakeholder engagement as key determinants of implementation. CONCLUSIONS: NIHR-funded intellectual disability research was no more likely than NIHR-supported studies to result in publications or guideline impact.