The Medicare Health Outcomes Survey (HOS) uses the Medical Outcomes Study (MOS) SF-36 among beneficiaries enrolled in Medicare managed care programs, whereas the Department of Veterans Affairs (VA), Veterans Health Administration (VHA) has administered the Veterans version of the SF-36 for quality management purposes. The Veterans version is comparable to the MOS version for 6 of the 8 scales, but distinctly different in role physical (RP) and role emotional (RE) scales. The gains in precision for the Veterans SF-36 provide evidence for the use of this version in future applications for assessing patient outcomes across health care systems.