Application of Instrumental Variable Analysis in Pediatric End-of-Life Research: A Case Study.

Instrumental variable analysis (IVA) has been widely used in many fields, including health care, to determine the comparative effectiveness of a treatment, intervention, or policy. However, its application in pediatric end-of-life care research has been limited. This article provides a brief overview of IVA and its assumptions. It illustrates the use of IVA by investigating the comparative effectiveness of concurrent versus standard hospice care for reducing 1-day hospice enrollments. Concurrent hospice care is a relatively recent type of care enabled by the Affordable Care Act in 2010 for children enrolled in the Medicaid program and allows for receiving life-prolonging medical treatment concurrently with hospice care. The IVA was conducted using observational data from 18,152 pediatric patients enrolled in hospice between 2011 and 2013. The results indicated that enrollment in concurrent hospice care reduced 1-day enrollment by 19.3%.