Only 12% of eligible hospitals signed up for the Centers for Medicare & Medicaid Services’ Bundled Payments for Care Improvement initiative and 47% of them dropped out within two years, according to a study reported today in the Journal of the American Medical Association. The voluntary program, launched in 2013, holds participants accountable for quality and costs for 30-, 60- or 90-day episodes of care. If cost targets are achieved, participants keep a portion of the savings; if cost targets are exceeded, participants reimburse Medicare a portion of the difference. The study evaluated model 2, which includes inpatient and post-acute spending and is the track selected by more than 99% of hospital participants. “Patterns of participation and dropout in the BPCI program suggest that for voluntary alternative payment models to have a broad effect on quality and costs of health care, barriers to participation and strategies for retention need to be addressed,” the authors said.