While the Health Information System (HIS) market is expanding fast, the fact remains that HIS capability in the majority of adopting hospitals remains low. In this study, we anchor on social exchange theory to study the effects of switching costs and contextual benefits on a physician's direct/indirect use preference, in the context of migration from stand-alone HISs to interoperable HISs supporting integrated electronic medical record. Survey results from 80 physicians in a public hospital reveal that previously identified cost and benefit factors exhibit different effects on a physician’s use preference. Specifically, a physician who perceives higher learning cost, more technical support and higher group deindividuation is more likely to prefer indirect use of an interoperable Computerized Physician Order Entry System (CPOES). Comparatively, a physician who perceives higher transaction cost and higher incentive in using the interoperable CPOES is more likely to prefer direct use of the system.