'Don't let the trial kill the intervention': how can researchers and care home teams implement complex intervention trials in care homes?

The profile of care homes has never been higher, and not necessarily for the best reasons[1]. The COVID-19 pandemic has had, and continues to have, a massive impact on care home residents[2] , their families, the staff and organisations who care for them, and surrounding local communities[3]. It has also highlighted the lack of good evidence based treatments tailored for this population, and the challenges of rapidly setting up and delivering trials to provide high quality evidence based care for COVID-19 (e.g. the PROTECT-CH trial www.protect-trial.net). The lessons learned from developing care home trials during COVID-19 are also relevant to other trials for conditions that are common in care home residents, such as delirium, dementia, falls, incontinence and pressure damage. Previous trials have often delivered inconclusive results, which is a waste of public funds, particularly as the infrastructure supporting these trials is developed for the specific study and dismantled once it is complete. This has led to the question of whether null results are due to avoidable aspects of trial design, leading to asking: 'did the trial kill the intervention?'[4] The qualitative systematic review by xxxxx (ref) provides useful guidance for researchers and care home partners on the implementation of research studies (not the implementation of findings after the study is completed). They performed a systematic literature review of several databases and the grey literature identifying in English, in high income countries, studies that were explicitly termed 'process evaluations'. Thirty-three studies were identified in the initial search in 2019, and a further 16 in an updated search in 2021 which confirmed the initial findings. We are aware of some studies that were not included e.g. [5], but the findings of these would largely support the conclusions drawn from the systematic review. The methodology used a human factors framework, SEIPS (Systems Engineering Initiative for Patient Safety). This conceptual model for identifying how the processes impact on outcomes places the person at the centre of a work system, acknowledging interactions with the internal environment, the organisation and tools/technology and tasks. Data (quotations) from included papers were coded as barriers or enablers of successful research implementation. By taking this approach, the researchers were able to evidence a broad range of challenges and solutions from different studies, and to synthesise these into a unifying framework providing the basis of recommendations for future research implementation. The most common domains which affected the implementation of the research interventions related to the compatibility of the task with existing working arrangements, and the time an