Quality management activities involve the application of scientific principles to performance improvement activities. With the plethora of available information, a systematic approach to evaluating the quality and usefulness of sources is necessary. One approach is critical appraisal, which is used to search for the best evidence or integrate evidence with clinical expertise. Two critical appraisal tools (CATs) are presented here, the first for any original clinical or health services research study and the second for research synthesis. The CAT scoring system and summaries of reviewed references facilitate understanding of the "state of the science" in the areas of interest.