Instruments to measure behavioural and psychological symptoms of dementia.

Reliable and valid measurement of behavioural and psychological symptoms of dementia (BPSD) is important for research and clinical practice. Here we provide an overview of the different instruments and discuss issues involved in the choice of the most appropriate instrument to measure BPSD in research. A list of BPSD instruments was generated. For each instrument Pubmed and SCOPUS were searched for articles that reported on their use or quality. Eighty-three instruments that are used to measure BPSD were identified. Instruments differ in length and detail, whether the interview is with participants, informants or by observation, the target sample and the time frames for use. Reliability and validity is generally good, but reported in few independent samples. When choosing a BPSD instrument for research the research question should be carefully scrutinised and the symptoms of interest, population, quality, detail, time frame and practical issues should be considered.