An application of a new evidence grading system to research on the chronic care model

Methodological quality undergirds all evidence-based medicine because without strong evidence supporting or refuting the efficacy of an intervention, the movement toward basing medical decisions and practice on scientific evidence is not sustainable. Recently, the consensus that had existed regarding the hierarchy of evidence produced by a study design was challenged on the basis that existing guidelines failed to properly define key terms, weight the merits of certain non-randomized controlled trials, and employ a comprehensive list of study design limitations to render evaluative conclusions, to name a few of the challenges. The present study introduces a new grading system that overcomes, or at the very least greatly diminishes, these challenges. This new method is applied to the literature on the Chronic Care Model and the results are then compared to several of the most popular grading guidelines currently in use. These results revealed substantial differences between the guidelines in accordance with previous research that challenged existing methods. Furthermore, the present study lends support to the proposed grading guideline although further research into its validity and reliability is needed.