Sample-size estimation is not reported in 24% of randomised controlled trials of inflammatory bowel disease: A systematic review

Background Sample-size estimation is an important factor in designing a clinical trial. A recent study found that 65% of Cochrane systematic reviews had imprecise results. Objective This study set out to review the whole body of inflammatory bowel disease (IBD) randomised controlled trials systematically in order to identify the reporting of sample-size estimation. Methods We conducted a comprehensive hand search of the Cochrane Library and Cochrane IBD Specialized Trials Register. We extracted information on relevant features and the results of the included studies. We produced descriptive statistics for our results. Results A total of 242 randomised controlled trials were included from 44 Cochrane systematic reviews. About 25% of the studies failed to report on sample-size estimation. Of those that did report on sample-size estimation, 33% failed to recruit their target sample size. Conclusions Around half of the randomised controlled trials in IBD either do not report sample-size estimation or reach their recruitment target with the level of detail in reporting being limited

Probiotics for maintenance of remission in ulcerative colitis

Ulcerative colitis is an inflammatory condition affecting the colon, with an annual incidence of approximately 10 to 20 per 100,000 people. The majority of people with ulcerative colitis can be put into remission, leaving a group who do not respond to first‐ or second‐line therapies. There is a significant proportion of people who experience adverse effects with current therapies. Consequently, new alternatives for the treatment of ulcerative colitis are constantly being sought. Probiotics are live microbial feed supplements that may beneficially affect the host by improving intestinal microbial balance, enhancing gut barrier function and improving local immune response

Dietary interventions for functional abdominal pain disorders in children: a systematic review and meta-analysis

Background Functional abdominal pain disorders (FAPDs) are common among children and are associated with decreased quality of life and school attendance. Several dietary interventions have been suggested to improve symptoms of FAPDs. This systematic review assessed the efficacy and safety of dietary interventions for pediatric FAPDs. Design and methods Electronic databases were searched (inception–October 2021). Systematic reviews or RCTs were included if children (4–18 years) with FAPDs were treated with dietary interventions and compared to placebo, no diet or any other diet. Data extraction and assessment of quality of evidence based on GRADE system was independently performed by two review authors. Outcomes were treatment success, pain intensity and frequency, and withdrawal due to adverse events. Results Twelve articles were included, representing data of 819 pediatric FAPD patients. Trials investigating fibers, FODMAP diet, fructans, fructose-restricted diet, prebiotic (inulin), serum-derived bovine immunoglobulin, and vitamin D supplementation were included. We found very low-certainty evidence that the use of fibers leads to higher treatment success (NNT = 5). Conclusion Based on current evidence, the use of fibers can be discussed in daily practice. High-quality intervention trials are highly needed to investigate if other dietary interventions are effective in the treatment of pediatric FAPD

Interventions for treating iron deficiency anaemia in inflammatory bowel disease: a network meta-analysis

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: The primary objective will be to evaluate the efficacy and harms of the interventions for the treatment of iron deficiency anaemia in people with inflammatory bowel disease and rank the treatments in order of effectiveness in a network meta‐analysis

P056 Power Calculations in Randomised Controlled Trials of Inflammatory Bowel Disease

Background: Sample size estimation is a vitally important calculation to make when designing a clinical trial. 25% of randomised controlled trials (RCTs) on interventions for Inflammatory Bowel Disease (IBD) have no power calculation (PC). We set out to systematically review RCTs reporting interventions for the management of IBD and to use the actual clinical data across these comparisons to produce data for minimum sample sizes that would achieve appropriate power. Methods: We included RCTs investigating any form of therapy for the treatment of IBD in patients of any age and interventions for either induction or maintenance of remission against control, placebo, or no intervention. The relevant data was extracted, and the studies were grouped according to the intervention used. We recalculated sample size and the achieved difference, as well as minimum sample sizes needed in the future. Results: A total of 105 trials were included. There was a large discrepancy between the estimated figure for the minimal clinically important difference used for power calculations and the actual differences seen. The minimum sample sizes to use in future trials were proposed based on the calculations made from actual achieved clinical differences from previous studies. Conclusion: A third of intervention studies in IBD within the last 25 years are underpowered, with large variations in the calculation of sample sizes. The resource containing sample size estimates constructed on the published evidence base is required for future researchers and key stakeholders within the IBD trial field