| Methods |
Placebo‐controlled, double‐blinded, and randomized according to a sequence used by the dispensing pharmacist. Patient population was stratified into four strata: 1‐ previous treatment, left‐sided disease; 2‐ previous treatment, universal disease; 3‐ no previous treatment, left‐sided disease; 4‐ no previous treatment, universal disease. Evaluation occurred at 3 weeks and 6 weeks |
| Participants |
Patients, ages 15 to 70 years, with mild to moderate ulcerative colitis seen at the Mayo Clinic (Rochester, Minn.) from September 1, 1984 to February 28, 1986 (N = 87). UC was defined by symptomatic, radiographic, endoscopic criteria. Colonic involvement was determined by flexible proctosigmoidoscopy with double‐contrast x‐ray films of colon or complete colonoscopy, or both. Newly or previously diagnosed cases were included. Patients receiving corticosteroids or SASP were required to stop such therapy at least 1 week prior to start of study. Pre‐entry evaluations included history, physical, blood count, chemistry screening, urinalysis, stool sample (had to be negative for ova, parasites, enteric pathogens) |
| Interventions |
Asacol tablets (400 mg of 5‐ASA, coated with pH‐sensitive polymer Eudragit‐S which dissolves at pH 7 or higher) or matching placebo (500 mg microcellulose with identical pH‐sensitive coating, n = 38) 4.8 g/day (n = 38) or 1.6 g/day (latter dose only used in stratum 1, n = 11), 12 tablets daily for 6 weeks. No pill count, but patients were asked about compliance |
| Outcomes |
Clinical response, described as 'complete', 'partial', or 'no response', was determined on the basis of stool frequency, amount of rectal bleeding, and physician's global assessment (which included sigmoidoscopic appearance) on 4‐point scales, compared to baseline data. 'Complete response' indicated resolution of all symptoms. Occurences of adverse reactions were also tabulated |
| Notes |
Early termination of treatment for any reason was deemed to constitute treatment failure |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Randomization sequence was developed by the Section of Medical Research Statistics, Rochester Methodist Hospital |
| Allocation concealment (selection bias) |
Low risk |
Centralized randomization by pharmacist |
| Blinding (performance bias and detection bias)
All outcomes |
Low risk |
Double‐blind: matching placebo |
| Incomplete outcome data (attrition bias)
All outcomes |
Unclear risk |
More placebo patients (n= 16) did not complete the study than 5‐ASA patients (n = 5). Placebo patients were more likely to drop out do to flare of UC or no improvement |
| 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 |
