The aims of this study were to determine the impact of irritable bowel syndrome on quality of life using a well-standardized measure, the SF-36, and to determine whether apparent impairments may be due to neuroticism. Undergraduate students with irritable bowel syndrome who had consulted a physician (41 females, 42 males), students with irritable bowel who had not consulted a physician (91 females, 74 males), and asymptomatic controls (52 females, 70 males) completed questionnaires on quality of life, neuroticism, and psychological distress. Patients showed greater impairment in quality of life than nonconsulters, who in turn showed greater impairment than controls. Neuroticism and psychological distress were correlated with all quality-of-life measures. However, when neuroticism and psychological distress were statistically partialed out, irritable bowel syndrome still had a significant negative impact. The SF-36 may be a useful outcome measure in treatment studies, but investigators will need to correct for confounding influences of neuroticism.