The review addressed a clear question and was supported by appropriate inclusion criteria. Several relevant data sources were searched with restriction to studies published in English, so language bias could not be ruled out. Publication bias was not assessed, but the authors acknowledged the possibility of publication bias as nine out of twelve articles were published in pharmacy journals. Two reviewers were involved in data extraction but the authors did not report how many reviewers were involved in study selection and quality assessment, so reviewer bias and error was possible.
The quality of the trials was moderate to poor. Due to the heterogeneity, results were appropriately presented in a narrative format. Control groups and supporting levels of statistical significance were not reported so it was not possible to verify the findings in the review. Most of the studies had smaller sample sizes, shorter follow-up and an involvement of higher numbers of pharmacists compared to normal clinical practice. It may not have been appropriate to combine studies with different interventions, treatment settings, populations and use of different outcome measures and medication adherence measures may not be appropriate which the authors acknowledged.
The authors’ conclusions reflect the evidence presented but given the potential for bias in the review process and limitations in the quality of the included trials, these conclusions should be considered tentative.