Assessment of benefit/risk of therapies for any disease is best conducted according to quantitative data. In many diseases, such as hypertension or hyperlipidemia, a single quantitative measure serves as a "gold standard" for patient status, but no single measure can serve as a "gold standard' for all individual patients with rheumatoid arthritis (RA). Therefore, indices such as the American College of Rheumatology (ACR) Core Data Set and Disease Activity Score (DAS), are used in clinical trials and other clinical research. These indices include 3 types of measures, which are derived from a health professional [joint counts, global]; a laboratory [erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)]; or a patient questionnaire [physical function, pain, global]. In most standard clinical care, the majority of clinicians do not collect joint count or patient questionnaire data at most visits. Therefore, assessment and management of most patients with RA is conducted empirically, with the only quantitative data from laboratory tests. Measures on a patient self-report questionnaire of physical function, pain, and global status, are as informative as joint counts, radiographic scores, laboratory tests, or any measure by a health professional to document status, estimate prognosis, and monitor responses to therapies. We suggest that quantitative measurement may be incorporated into standard clinical care most easily and effectively by asking each patient to complete a simple 1-page questionnaire at each visit to a rheumatologist.