CRD Summary: This review assessed the impact of mycophenolic acid (MPA) monitoring on health outcomes including rejection and adverse events in solid organ transplant patients. The authors concluded that there is almost no evidence to suggest that MPA monitoring affects these outcomes. This was a well-conducted review and the conclusion is likely to be reliable.

CRD Commentary: The review questions and the inclusion criteria were clear. The authors searched a number of relevant databases and made additional efforts to identify studies. However, the decision to limit the review to published studies reported in English might have increased the possibility that some relevant studies were not included in the review. The authors reported using methods designed to minimise bias and error in the study selection, validity assessment and data extraction processes. The validity assessment used appropriate criteria and was utilised in the synthesis. Given the clinical and methodological heterogeneity of the included studies, the decision to employ a narrative synthesis appears appropriate. This was a well-conducted review and the authors' conclusions accurately reflect the paucity of available evidence.