Assessment of comprehensiveness of Medicare Part B provider-level data sets within dermatology.

Publicly available provider-level Medicare Part B data sets have been increasingly utilized for health services research in dermatology. Despite offering detailed insights, an important limitation of these data sets is suppression of services performed for < 11 Medicare beneficiaries at the level of each provider. This longitudinal review assesses the magnitude of this limitation by comparing service counts in provider-level Medicare data sets to those in aggregate data sets, ultimately identifying a concordance rate of 94.3% for dermatology services. However, facility-based visits (52.5%), inpatient evaluation and management visits (59.7%), phototherapy (62.9%), incision and drainage (61.1%), and nail procedures (38.0%) were less well-represented in the provider-level data sets. Provider-level data sets are most suitable for assessing dermatology services in aggregate and among specific high-volume procedure groups but alternative data sets should be considered when investigating inpatient services, facility-based services (more common in certain states), or rarely performed procedures.