The outcome movement in medicine has encouraged the development of patient-answered questionnaires as measures of well-being. A disease-specific questionnaire for carpal tunnel syndrome (CTS) was introduced by Levine et al. in 1993. We evaluated this questionnaire in 156 consecutive new patients presenting with pain, numbness, or tingling of the upper extremity. Of these, 114 correctly filled out the carpal tunnel outcome instrument. In addition, these patients completed the self-administered hand diagram developed by Katz and Stirrat for the diagnosis of CTS. The 114 patients were classified according to their hand diagram as classic or probable CTS (n = 47), possible CTS (n = 31), and unlikely CTS (n = 36). The mean symptom severity score in patients classified as classic or probable CTS was significantly higher than the mean score in patients classified as possible or unlikely CTS (p < .01). The mean scores of items regarding sensory symptoms were significantly higher in patients with classic or probable CTS compared to patients with possible or unlikely CTS (p < .0001). The scores were similar for CTS and non-CTS patients on the functional status subscale.