Background/Aims: Competing theories exist regarding the causes and nature of behaviours that challenge (BC). The present study attempted to provide better insight into these behaviours and determine whether there were any underlying relationships for people living in care homes with and without dementia. Methods: Cross sectional data for 2185 residents living in 63 UK care homes using the Challenging Behaviour Scale were collected. The incidence (i.e. presence/absence) of 25 commonly reported behaviours that challenge staff were determined using dichotomous scoring. Cluster analysis and Mokken scaling were used to examine underlying relationships. Mokken is a method of analysing data to determine whether there is a ‘latent’ structure within a data set. Results: The prevalence of reported BC was 87.5%. Cluster analysis revealed three main clusters: apathy, agitation with internal focus, agitation with active external focus. For seven of the 25 items a hierarchical model emerged, where behaviours at the bottom of the hierarchy tended to occur in the presence of those higher up. Behaviours at the bottom of the hierarchy (dangerous behaviour) were less frequently observed than the items at the top (lack of self-care, verbal aggression). Conclusion: Some common BC may occur in groups and themed clusters. This study has shown that a hierarchical structure of BC in residents may be present. The findings testify to the complexity in the aetiology and treatment of BC and hence the need for focussed high intensity bio-psychosocial interventions to be targeted towards those with high levels of ‘unmet need’. Implications for future research and practice are discussed
