How best to capture the impact of complementary therapies in palliative care: A systematic review to identify and assess the appropriateness and validity of multi-domain tools

BACKGROUND: Complementary therapies are widely used in palliative care settings. Qualitative research found that people with advanced disease report a range of physical and psychological benefits from complementary therapies, however evidence of their effectiveness from clinical trials is inconclusive. This may be because trials are limited by use of inappropriate outcome measures. AIMS: To identify tools which capture the impact of massage, reflexology and aromatherapy in people with advanced disease. We (1) identified multi-domain tools used to evaluate these therapies in populations with any chronic health condition and (2) assessed whether tools were valid and psychometrically robust in populations with advanced disease. DESIGN: A two-stage systematic review was conducted using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines (PROSPERO: CRD42020161199). DATA SOURCES: Six databases were searched (August 2021). Study methodological quality, tool psychometric properties and evidence quality were assessed. A global comparison score was generated. RESULTS: Stage 1: 66 trials using 40 different multi-domain tools were identified. Stage 2: Of these tools, we identified papers for seven tools regarding development or validation in advanced disease populations. The majority of psychometric data were inconsistent or inconclusive. Data were mostly of low quality due to methodological issues. CONCLUSION: Of the tools identified, ‘Functional Assessment of Cancer Therapy – General’ appears to be the most suitable alternative tool against COMSIN criteria, for trials of massage, reflexology and aromatherapy in palliative care. Further tool validation is required before firm recommendations can be made. Co-development of a core outcome set could ensure relevant domains are assessed.