Specialized managerial expertise, coupled with the threat of non-renewal should improve efficiency in firms that opt for contract management arrangements. To examine this we apply a generalized version of tests for expense preference behavior to U.S. hospitals in the 1990s. Extending prior literature, we create a quasi-experimental design for a comparison of adopters and non-adopters of contracts using propensity score methods. We generate the distribution of ‘expense preference’ parameters for all contract adopters in both the pre- and post-adoption states, and for a matched control group of non-adopters over the same period. Our results show that contract adoption leads to reduced expense preference behavior, but that this result depends critically on the input being examined.