The inclusion of informal care in applied economic evaluation: a review.

OBJECTIVE: Theory and guidelines advocating the inclusion of informal care in economic evaluation have, in recent years, been accompanied by developments in the methods for capturing the costs and outcomes related to informal care. The objective of this study was to review applied economic evaluations to identify the methods used for, and implications of, including informal care in practice.
METHODS: Searches of key databases were conducted to identify all full economic evaluations incorporating costs or outcomes relating to informal care. Information was extracted by using a standard template from all studies meeting the inclusion criteria.
RESULTS: Thirty economic evaluations were identified that included informal care. Twenty-five of these studies costed carers' time input and 17 measured outcomes for carers. The reported cost-effectiveness of interventions was altered by including informal care, in some cases changing the key conclusions for health care funding.
CONCLUSIONS: Theory and methods development around informal care are yet to significantly permeate the applied literature; however, the results suggest that some funding priorities may change if they were to do so. The development of 1) a reference case for including informal care; 2) sensitivity analysis for contentious issues; and 3) a statement for the reason for excluding informal care, if this is deemed appropriate, may help to improve the way that informal care is included in economic evaluations in the future.