The aim of the present investigation was to assess and compare health status instruments in SLE. One hundred and twenty-five patients completed five health status instruments: the Health Assessment Questionnaire (HAQ), Functional Ability Index, the Fatigue Severity Scale (FSS), the Disability Days Measure (DDM), the Centre for Epidemiological Studies-Depression Scale (CES-D), and the Medical Outcomes Study (MOS) Short Form Health Survey during their Clinic visit. Disease activity was measured using the SLE Disease Activity Index (SLEDAI). All instruments described a spectrum of quality of life outcomes in these patients. An inter-instrument correlation analysis revealed that components of the MOS correlated significantly with each of the other instruments used. There was no correlation between any of the instruments used and the SLEDAI. We conclude that health status assessment as measured by the MOS short form is a valid independent outcome measure in patients with SLE.