Table 2 Comparison of implicit and explicit methods of data extraction in case-note review
ImplicitExplicit
Advantages
Easy to develop and administerExplicit (evidence based) criteria
High face validity, since experts define ‘good’ and ‘bad’ careReproducible
Self-updating through use of expertsEasy to explain low score in terms of criteria—which may narrow score of improvement efforts
Reflects the full scope of clinical decisions that apply to a particular patientCan be conducted by researchers rather than expert clinicians, once the criteria have been agreed, reducing costs
Involves physicians and other expert clinicians in the quality of care process
Disadvantages
Requires (expensive) clinical expertsRequire training of reviewers
More arbitrary than evidence basedNeed to be updated constantly
Developed principally for inpatient careLimited scope in terms of content and context (relevant populations)
Poor reproducibility of judgementsDoes not capture the subtleties of health care (eg, contraindications)
Expensive
Potential for gaming
Need to decide how to analyse multiple criteria
Possible bias if different numbers of criteria apply to patients between comparative sites, particularly if some criteria are harder to meet than others