Rao 1989.
| Study characteristics | ||
| Methods | Randomized, double‐blind, double‐dummy, multicenter comparison of Olsalazine and SASP. At entry and at 4 weeks, participants were assessed clinically, by sigmoidoscopy, rectal biopsy, blood tests, stool samples and urine analysis. Participants also kept stool diary records | |
| Participants | Outpatients with a first attack of mild to moderately‐severe ulcerative colitis, confirmed by sigmoidoscopic and histologic evidence and negative stool cultures (N = 37) | |
| Interventions | Olsalazine, 2 g/day (n = 20), or enteric‐coated SASP, 3 g/day (n = 17), provided in sealed blister packs, administered 4 times a day. Full dosage was reached after 7 days and continued for 4 weeks. Double‐dummy technique required each participant to take a physically indistinguishable dummy containing mainly potato starch. Compliance was confirmed by pill counts | |
| Outcomes | Changes in daily stool frequency and consistency, sigmoidoscopic and histological appearance, and clinical assessments were defined as 'improved' (an increase by at least 1 point), 'unchanged' or 'worsened'. Remission was defined as the lack of blood in stool, no more than 2 bowel movements a day, and no systemic disturbance. Overall improvement was defined as a positive change in at least 2 of the above criteria | |
| Notes | Pharmacia Limited supplied the double dummy packs containing olsalazine
capsules and sulphasalazine tablets Funding support and conflicts of interest were not reported |
|
| 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. Participants received Olsalazine or sulphasalazine along with physically‐indistinguishable dummies. The drugs were provided in sealed blister packs |
| Incomplete outcome data (attrition bias) All outcomes | Unclear risk | 3 participants in the Olsalazine group did not complete the study, compared with 4 participants in the SASP group. Reasons for withdrawal were not given |
| 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 |