Analysis of length-of-stay differences between investor-owned and voluntary hospitals.

In contrast to assertions that investor-owned (I-O) hospitals are more efficient than voluntary hospitals, this study finds no significant difference between I-Os and voluntaries where the efficiency measure is length of hospitalization (LOH). The data base used is a national probability sample of hospitals and patients. The analysis accounts for variation in LOH by controlling for hospital characteristics other than ownership, and in particular it utilizes a new case-mix index to control for the case-mix portion of heretofore suggested differences.