Background: Trials are at risk of contamination bias which can occur when participants in the control group are inadvertently exposed to the intervention. This is a particular risk in rehabilitation studies where it is easy for trial interventions to be either intentionally or inadvertently adopted in control settings. The Falls in Care Homes (FinCH) trial is used in this paper as an example of a large randomised controlled trial of a complex intervention to explore the potential risks of contamination bias. We outline the FinCH trial design, present the potential risks from contamination bias, and the strategies used in the design of the trial to minimise or mitigate against this. The FinCH trial was a multicentre randomised controlled trial, with embedded process evaluation, which evaluated whether systematic training in the use of the Guide to Action Tool for Care Homes reduced falls in care home residents. Data were collected from a number of sources to explore contamination in the FinCH trial. Where specific procedures were adopted to reduce risk of, or mitigate against, contamination, this was recorded. Data were collected from study e-mails, meetings with clinicians, research assistant and clinician network communications, and an embedded process evaluation in six intervention care homes. During the FinCH trial, there were six new falls prevention initiatives implemented outside the study which could have contaminated our intervention and findings. Methods used to minimise contamination were: cluster randomisation at the level of care home; engagement with the clinical community to highlight the risks of early adoption; establishing local collaborators in each site familiar with the local context; signing agreements with NHS falls specialists that they would maintain confidentiality regarding details of the intervention; opening additional research sites; and by raising awareness about the importance of contamination in research among participants. Conclusion: Complex rehabilitation trials are at risk of contamination bias. The potential for contamination bias in studies can be minimized by strengthening collaboration and dialogue with the clinical community. Researchers should recognise that clinicians may contaminate a study through lack of research expertise.

Despite an increasing number of sources providing information and advice about dementia, those living with the condition feel inadequately informed. The reasons for this remain unclear. This study has three aims: to identify where people with dementia and their carers currently access dementia-related information from; to determine how accessible, credible and comprehensible people with dementia and their carers consider the available sources of information; and to determine how people with dementia and their carers would like to receive information. An online or postal survey was completed by 171 female and 41 male participants with a close family member or friend with dementia. Accessibility above quality held the greatest influence over an individual's use of an information source. Participants preferred relational sources such as healthcare professionals as these were able to give individualised information, yet these were poorly accessible and lacked dementia specific knowledge. Therefore, individuals used non-relational sources such as the internet. However, increased use of the internet was linked to feeling overwhelmed by information. It was not the end result of the information search but the effort taken to reach the information that influenced participant's perception of information gathering. Future research should look at ways of designing and providing accessible information sources that act and feel like relational contact.

The objective was to explore the ways in which people with dementia and their carers adapt their homes, including the barriers and use of available information. Semi-structured interviews were conducted with ten people with dementia and their informal carer. The collected data were analysed using thematic analysis. Three core themes emerged: Maintaining familiarity and coping with change, Having knowledge and finding knowledge and Meeting challenges through home adaptation. The most significant barriers to making home adaptations were lack of knowledge and maintaining familiarity. Having more information and making home modifications earlier might enable individuals with dementia to adjust to their adapted environment.

Objectives To determine the clinical and cost effectiveness of a multifactorial fall prevention programme compared with usual care in long term care homes. Design Multicentre, parallel, cluster randomised controlled trial. Setting Long term care homes in the UK, registered to care for older people or those with dementia. Participants 1657 consenting residents and 84 care homes. 39 were randomised to the intervention group and 45 were randomised to usual care. Interventions Guide to Action for Care Homes (GtACH): a multifactorial fall prevention programme or usual care. Main outcome measures Primary outcome measure was fall rate at 91-180 days after randomisation. The economic evaluation measured health related quality of life using quality adjusted life years (QALYs) derived from the five domain five level version of the EuroQoL index (EQ-5D-5L) or proxy version (EQ-5D-5L-P) and the Dementia Quality of Life utility measure (DEMQOL-U), which were self-completed by competent residents and by a care home staff member proxy (DEMQOL-P-U) for all residents (in case the ability to complete changed during the study) until 12 months after randomisation. Secondary outcome measures were falls at 1-90, 181-270, and 271-360 days after randomisation, Barthel index score, and the Physical Activity Measure-Residential Care Homes (PAM-RC) score at 91, 180, 270, and 360 days after randomisation. Results Mean age of residents was 85 years. 32% were men. GtACH training was delivered to 1051/1480 staff (71%). Primary outcome data were available for 630 participants in the GtACH group and 712 in the usual care group. The unadjusted incidence rate ratio for falls between 91 and 180 days was 0.57 (95% confidence interval 0.45 to 0.71, P<0.001) in favour of the GtACH programme (GtACH: six falls/1000 residents v usual care: 10 falls/1000). Barthel activities of daily living indices and PAM-RC scores were similar between groups at all time points. The incremental cost was £108 (95% confidence interval −£271.06 to 487.58), incremental QALYs gained for EQ-5D-5L-P was 0.024 (95% confidence interval 0.004 to 0.044) and for DEMQOL-P-U was 0.005 (−0.019 to 0.03). The incremental costs per EQ-5D-5L-P and DEMQOL-P-U based QALY were £4544 and £20 889, respectively. Conclusions The GtACH programme was associated with a reduction in fall rate and cost effectiveness, without a decrease in activity or increase in dependency. Trial registration ISRCTN34353836 .