Assessing the impact of clinical guidelines: research lessons learned

Clinical guidelines are proliferating. Here, a theoretical and practical perspective is presented on how to evaluate the effectiveness of guidelines and lessons learned from impact studies conducted. A nosology of guidelines is presented, along with the rationale for evaluating key dimensions, including degree of implementation, impact on process, outcomes, and cost of care, as well as provider and patient satisfaction. Key methodologic problems in evaluation and some possible ways to address them are addressed. Rapid and practical evaluation of clinical guidelines is a critical step that can both confirm their usefulness and direct their revision and improvement.