Oyo-Ita, A., Wiysonge, C.S., Oringanje, C., Nwachukwu, C.E., Oduwole, O., and Meremikwu, M.M. (2016) Interventions for improving coverage of childhood immunisation in low- and middle-income countries. Cochrane Database of Systematic Reviews, 7. Art. No.: CD008145Link to Source
The review has clear inclusion criteria, literature searches are well-documented and the authors report a comprehensive screening and data extraction process. They use a recognised tool for risk of bias assessment and synthesise findings using meta-analysis. It is not clear if the authors contacted experts to identify additional studies and this is a minor limitation.