Quality of therapeutic drug monitoring guidelines is suboptimal: an evaluation using the Appraisal of Guidelines for Research and Evaluation II instrument.

Objectives: Although therapeutic drug monitoring (TDM) guidelines are available, systematic evaluations of their methodological quality are scarce. This study aimed to assess the quality of current TDM guidelines using the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument.

Study Design And Setting: We performed a systematic search to identify the relevant TDM guidelines in PubMed, EMBASE, CNKI, Wan Fang Database, CBM, VIP, four main guideline databases (NICE, NGC, GIN, and WHO guideline databases), and official websites of the governments and societies associated with TDM from the inception date to May 2018. Four independent appraisers rated the quality of each TDM guideline using the AGREE II instrument, and the mean score of each AGREE II item was calculated. The overall agreement among the appraisers was evaluated using the intraclass correlation coefficient (ICC).

Results: Twenty-eight TDM guidelines satisfied the eligibility criteria from among 12,235 references. The overall agreement among the appraisers was substantial (0.700-0.880). The mean scores for the six AGREE II domains were scope and purpose, 67.7% (95% CI, 64.0-71.4%); stakeholder involvement, 39.8% (95% CI, 33.3-46.3%); rigor of development, 36.0% (95% CI, 28.1-43.9%); clarity and presentation, 61.6% (95% CI, 55.7-67.4%); applicability, 30.6% (95% CI, 26.4-34.8%); and editorial independence, 49.2% (95% CI, 40.0-58.6%). The reviewers recommended only four guidelines, and most of the TDM guidelines were rated as "recommended with modifications."

Conclusion: Overall, the quality of TDM guidelines is suboptimal according to the evaluation using the AGREE II instrument. The domains of applicability, rigor of development, stakeholder involvement, and editorial independence of the guidelines need to be reported. In addition, guideline developers closely adhering to the AGREE II instrument and the Grading of Recommendations Assessment Development and Evaluation system are required to draft high-quality and reliable TDM guidelines.