Patient-reported outcome measures for cancer caregivers: a systematic review

Informal caregivers provide invaluable help and support to people with cancer. As treatments extend survival and the potential burdens on carers increase, there is a need to assess the impact of the role. This systematic review identified instruments that measure the impact of caregiving, evaluated their psychometric performance specifically in cancer and appraised the content.

A two-stage search strategy was employed to: (1) identify instruments that measure the impact of caregiving, and (2) run individual searches on each measure to identify publications evaluating psychometric performance in the target population. Searches were conducted in MEDLINE, EMBASE, CINAHL and PsycINFO and restricted to English for instrument used and article language. Psychometric performance was evaluated for content and construct validity, internal consistency, test-retest reliability, precision, responsiveness and acceptability. Individual scale items were extracted and systematically categorised into conceptual domains.

Ten papers were included reporting on the psychometric properties of eight measures. Although construct validity and internal consistency were most frequently evaluated, no study comprehensively evaluated all relevant properties. Few studies met our inclusion criteria so it was not possible to consider the psychometric performance of the measures across a group of studies. Content analysis resulted in 16 domains with 5 overarching themes: lifestyle disruption; well-being; health of the caregiver; managing the situation and relationships.

Few measures of caregiver impact have been subject to psychometric evaluation in cancer caregivers. Those that have do not capture well changes in roles and responsibilities within the family and career, indicating the need for a new instrument.