| Methods |
Multicenter, randomized, double‐blind, double‐dummy comparison of SASP and olsalazine. Clinical assessments were performed after every 3 months or more frequently if relapse was suspected. Rigid sigmoidoscopy was performed at entry and after 6 and 18 months |
| Participants |
Patients with ulcerative colitis in remission, with at least 2 episodes of active disease during the last 5 years. No other concomitant medications were permitted (N = 322) |
| Interventions |
Olsalazine, 1 g/day, with SASP‐matched placebo (n =161) or active SASP, 2 g/day, with olsalazine‐matched placebo (n = 161) for either 6, 9, 12, 15 or 18 months. Patients were instructed to take medication with meals. Full treatment regimen was reached after 7 days. Compliance was verified by pill counts |
| Outcomes |
Relapse was defined as macroscopic changes in the rectum of grade 3 or 4 on a 4‐point scale. Other measures of efficacy were changes in number of stools per day, blood in stools, and consistency of stools. The failure rates were reported on an intention‐to‐treat basis |
| Notes |
|
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Unclear risk |
Not described |
| Allocation concealment (selection bias) |
Low risk |
A ‐ Adequate |
| Blinding (performance bias and detection bias)
All outcomes |
Low risk |
Double‐blind, double‐dummy (matched placebos) |
| 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 |
