Quality of life is affected by the creation of a stoma. To assess the validity of the Ostomy Function Index in patients with a stoma, a prospective survey was conducted from July 2000 to September 2001 among patients participating in local United Ostomy Association chapters (N = 99; 55 with a colostomy and 44 with an ileostomy). The Short Form 36 general health survey, Fecal Incontinence Quality of Life Scale, and the proposed Cleveland Clinic Florida Ostomy Function Index were used to assess general health and stoma function in patients with an ostomy. The average proposed function index score (7 = excellent function, 35 = poor function) was 11.97 (range 7 to 22). The proposed function Index correlated with the Fecal Incontinence Quality of Life Scale and the physical and mental component scales of the SF-36 (P < 0.05). The correlation between the proposed function index and the Fecal Incontinence Quality of Life Scale was stronger in colostomy than in ileostomy patients. With the exception of the SF-36 role-emotional domain in ileostomy patients, the function index correlated with all SF-36 scales (P <0.05) in both patient groups. The results of this study suggest that ostomy function is variable and correlates with quality of life and that the Fecal Incontinence Quality of Life Scale offers a limited assessment of quality of life in colostomy patients. The Cleveland Clinic Florida Ostomy Function Index offers an objective assessment of ostomy function that reflects on quality of life. Additional studies to refine measurement of quality of life in stoma patients are warranted.