| Methods |
Multi‐centre, randomised, double‐blind, double‐dummy, parallel group study |
| Participants |
Adult patients (18 to 80 years) with moderate to severely active ulcerative colitis confirmed by flexible sigmoidoscopy (N = 99) |
| Interventions |
Balsalazide (2.25 g three times daily: 6.75 g/day, n = 50) or Asacol (0.8 g three times daily: 2.4 g/day, n = 49) for 12 weeks |
| Outcomes |
The primary outcome was the proportion of patients achieving complete remission (based on diary card) by 12 weeks. Patients left the study at weeks 4 or 8 if they achieved complete remission. Complete remission was defined as none or mild symptoms sigmoidoscopic grade of 0 or 1 and no use of rectal steroid foam. Other outcomes included patient and investigator satisfaction, laboratory assessments, median time to relief of symptoms, cumulative days free of symptoms, study dropouts, dropouts due to treatment failure and adverse events. Outcomes were evaluated at entry and weeks 2, 4, 8 and 12. Adherence was assessed at follow‐up visits |
| Notes |
Patients were provided with rectal steroid foam as relief medication for use as required |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Unclear risk |
Not described |
| Allocation concealment (selection bias) |
Unclear risk |
Not described |
| Blinding (performance bias and detection bias)
All outcomes |
Low risk |
Double‐blind, double‐dummy: Placebos of identical appearance to the balsalazide capsules and mesalamine tablets were provided. Patients received three capsules (balsalazide/placebo) and two tablets (mesalamine/placebo) three times daily |
| Incomplete outcome data (attrition bias)
All outcomes |
High risk |
Thirty‐eight percent of the patients (38 of 101) did not complete the study (15 balsalazide; 23 mesalamine), the main reason being treatment failure, which was more common in the mesalamine group (6 balsalazide; 16 mesalamine; P = 0.015). Other reasons for withdrawal included noncompliance with the study protocol (6 balsalazide, 3 mesalamine), unacceptable adverse events (1 balsalazide, 1 mesalamine), and treatment with excluded medication (1 balsalazide, 1 mesalamine). Three patients (1 balsalazide, 2 mesalamine) who were erroneously included into the study were also withdrawn; 1 patient receiving balsalazide did not have UC, 1 patient receiving mesalamine was not using adequate contraception, and 1 patient receiving mesalamine was included into the study after the recruitment deadline had passed |
| 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 |
