Predictors of high quality clinical practice guidelines: examples in oncology

Objective. Clinical practice guidelines are widely used as effective tools for improving the management of patients with cancer. However, there is increasing concern about variation in guideline quality. In this study we identified predictors for high-quality guidelines in oncology. Design. The quality scores for 32 oncology guidelines from 13 countries were determined by four independent appraisers using the Appraisal of Guidelines for Research and Evaluation (AGREE) instrument. Main measures. The contribution to the quality score of six characteristics of guidelines and three of guideline developing organizations was then assessed using analysis of variance and stepwise linear regression analysis. Results. Some guideline and organizational characteristics were shown to be responsible for a large part of the variations in quality scores. The availability of background information was the strongest predictor of quality with an explained variance ranging from 17% ('Applicability) to 67% ('Rigour of development'). High-quality guidelines were more often produced by government-supported organizations and/or within a structured, coordinated programme. The other characteristics (publication year, type of guideline, format, level of care, and scope) were not independent predictors of quality. Conclusions. Guidelines should provide more explicit information about the context of their development and methods used in order to improve their quality and thus encourage their use in clinical practice.