Giving health-care providers a lump sum payment for certain treatments – touted as a way to save money and improve coordination of care — yielded disappointing results for some major California hospitals and insurers, a study found. The RAND Corp. study, funded by a $2.9-million federal grant, looked at "bundled payments" for care of insured orthopedic patients under 65 at a handful of large hospitals and insurers in California. Six of the state's biggest insurers and eight hospitals started out in a pilot program in 2010, but only three insurers and two hospitals actually decided to enter contracts to adopt bundled payments.