Table 2. RCTs eligible for inclusion in the dietary intervention in IBS systematic review.

Author	Design	Participants	Interventions	Methodology	Outcomes
Atkinson et al.10	UK RCT, single center.	150 Rome II IBS. Tested for food serum IgG assay. Recruited from secondary care; 83% female.	Diet avoiding foods that they were intolerant of, according to IgG assay or sham diet for 12 weeks.	Method of randomization and concealment of allocation not stated. Double-blind. Other IBS medications allowed.	Patients asked “Compared with your IBS before you started the food elimination diet, are you now: terrible, worse, slightly worse, no change, slightly better, better, or excellent?” Better or excellent was taken as significant improvement
Biesiekierski et al.11	Australian RCT, single	39 Rome III IBS patients intolerant of gluten, but celiac excluded. Recruited from newspaper advertisement; 89% female.	Diet spiked with 16 g gluten per day vs. placebo for 4 weeks.	Adequate method of randomization and concealment of allocation. Double-blind. No other IBS medications allowed.	Patients answering “no” to the question “Over the last week were your symptoms adequately controlled?”
Staudacher et al.12	UK RCT, single center	41 Rome III IBS. Recruited from secondary care. Bloating and/or diarrhea included, predominant constipation excluded.	FODMAPs diet vs. habitual diet for 4 weeks.	Method of randomization and concealment of allocation not stated. Open study—patients not blinded (unclear if researchers masked).	GI symptom rating scale. Patients asked “Were your symptoms adequately controlled over the previous week?”

FODMAPs, Fermentable Oligo-Di-Monosaccharides and Polyols; GI, gastrointestinal; IBS, irritable bowel syndrome; IgG, immunoglobulin G; RCT, randomized controlled trial.