This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordBackground: Very few interventional studies have directly examined the impact of treatment approaches on health-related quality of life (HRQL) in people with dementia. This is of particular importance in therapies to address behavioural symptoms, where HRQL is often severely affected. Methods: Analysis within the WHELD cluster randomised factorial study in 16 UK care homes examining the impact of person-centred care in combination with antipsychotic review, social interaction and exercise interventions. This study analysed impact on HRQL through the DEMQOL-Proxy. Results: Data on HRQL were available for 187 participants. People receiv...