Quality assessment of clinical practice guidelines using the AGREE instrument in Japan: A time trend analysis

Clinical practice guidelines (CPGs) are representative methods for promoting the standardization of healthcare and improvement of its quality. Few studies have investigated changes in the quality of CPGs published in a country over time. Our aim was to investigate changes in the quality of CPGs over time in the context of the available infrastructure for CPG development, public interest in healthcare quality, and healthcare providers' responses to this interest.

All CPGs pertaining to evidence-based medicine (EBM) issued between 2000 and 2014 in Japan (n = 373) were evaluated using the Japanese version of the Appraisal of Guidelines for Research and Evaluation (AGREE) I. Additionally, time trends in quality were analyzed. Using a cut-off point based on the publication year of CPG development literature, the evaluated CPGs were classified into those published until 2008 (pre-2008) and those published since 2009 (post-2008). Subsequently, we compared these groups in terms of 1) first edition CPGs and its second editions, and 2) patients' version of CPGs.

Scores on all six domains of AGREE I improved each year. A comparison of the first- and second-edition of CPGs (n = 64) showed that scores on all domains improved significantly after revision. Significant improvement was observed in three domains (#2 stakeholder involvement, #3 rigor of development, and #4 clarity of presentation) in the pre-2008 group and in all domains in the post-2008 group. The comparison between the pre- and post-2008 groups in terms of CPGs for patients showed that the score increased in only one domain (#1 scope and purpose).

The number of published CPGs has been increasing and the quality of CPGs, as assessed using the AGREE I instrument, has been improving. These changes seem to be influenced by improvements in social infrastructure, such as the publication of CPG development procedures, availability of CPG preparation methodology training, and increase in CPG-related skills.