Nonsteroidal antiinflammatory drugs, ulcers and risk: a collaborative meta-analysis

CRD COMMENTARY: Many details are missing from this report of a systematic review. The review question is not very clear and the literature search uses only MEDLINE, which may have led to non-English language studies being missed. Inclusion criteria are not fully set out (no inclusion criteria relate to participants) and details are not given of study selection and data extraction procedures. Validity assessment of included studies was not undertaken. Very few study details are given and only selected summary estimates of risk are given in the paper. There is not enough information given to say whether the author's conclusions follow from the results.