Introduction Although current guidelines recommend Small-Bowel Capsule Endoscopy (SBCE) for the evaluation of patients with obscure gastrointestinal bleeding (OGIB), its role in investigating patients with iron deficiency anaemia (IDA) alone is still unclear.

Aim To evaluate the diagnostic yield (DY) of SBCE in patients with IDA by means of a systematic review of studies reporting this data.

Methods A recursive literature search (sources: Medline and Embase) of studies reporting DY of SBCE in patients with IDA was undertaken (November 2011). The search was restricted to fully reported papers in English, published between January 2001 and November 2011, including adult patients and clearly reporting DY for IDA patients. Studies were selected and evaluated separately by two of the authors. Data on DY were extracted, pooled, and analysed. Any discrepancy in papers selection or in data extraction was solved by consensus. The QUADAS tool was used to assess the study for methodological quality. Statistical analysis was performed with STATA version 12.0.

Results A total of 27 (7 prospective, 20 retrospective; total of 1943 patients) studies was selected for final review and analysis. Five studies (including 316 patients) were specifically designed to evaluate only IDA patients; in the remaining 22 studies, the patients with IDA represented a subgroup of patients undergoing SBCE. Overall, the 27 studies were of poor to moderate quality. The overall pooled DY, estimated by applying the random effect model (I²: 77.7%), was 48.2% (95% CI 43.1 to 53.4%) while it was 53.4% (95% CI 34.7 to 72.0%) and 47.2 % (95% CI 42.1 to 52.2%) for studies focusing and not focusing on IDA patients, respectively.

Conclusion Although the studies evaluating the DY of SBCE in IDA are of poor to moderate quality and heterogeneous, the estimated DY is about 50% and seems to be comparable with that observed in patients with OBIG.

Competing interests None declared.