| Methods |
Multicenter, double‐blind, placebo‐controlled, computer‐randomized trial involving 5 university‐based medical centres, one inflammatory bowel disease center, and 3 private practice sites. Patients were not stratified according to clinical characteristics. Initial patient evaluation and follow‐up exams consisted of lab tests, flexible proctosigmoidoscopy and radiographic films or colonoscopy at entry, followed by sigmoidoscopy at 3 and 6 weeks |
| Participants |
Patients, ages 18 to 75 years, with mildly to moderately active ulcerative colitis were enrolled from November 1988 to June 1989 (N = 158). Diagnosis by symptomatic, radiographic, and endoscopic criteria had to have been confirmed by colonoscopy, proctosigmoidoscopy or barium enema within 24 months of start of study. Cases of both newly and previously diagnosed disease showing continued active signs, despite SASP therapy were included. Steroid therapy had to be stopped at least one month before start of study; SASP and topical rectal therapies were discontinued at least 1 week before start. Concomitant use of corticosteroids, aspirin, NSAIDs, metronidazole, 6‐mercaptopurine, azathioprine, cyclosporine, or other investigational drugs was not permitted |
| Interventions |
1.6 g/day (n = 53) or 2.4 g/day (n = 53) oral mesalamine (Asacol) in 400 mg tablets coated with pH‐sensitive polymer (Eudragit‐S) or matching placebo tablets (n = 52) containing microcellulose. Compliance was checked by pill count at each visit and by review of patient diaries |
| Outcomes |
Clinical grading was based on stool frequency, rectal bleeding, sigmoidoscopic findings, and patient's functional assessment, each on 4‐point scale, which together gave the 'physician's global assessment', also on a 4‐point scale. The change in this clinical grade was indicated by classifying each patient as being 'in remission', 'improved', 'maintained', or 'worsened'. Withdrawals and adverse side effects were also reported |
| Notes |
|
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Computer‐generated |
| Allocation concealment (selection bias) |
Unclear risk |
Not described |
| Blinding (performance bias and detection bias)
All outcomes |
Low risk |
Double‐blind: matching placebo |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
Drop‐outs balanced across intervention groups with similar reasons for withdrawal |
| Selective reporting (reporting bias) |
Low risk |
Expected outcomes were reported |
| Other bias |
Low risk |
The study appears to be free of other sources of bias |
