Representativeness of the Get With The Guidelines-Stroke Registry: comparison of patient and hospital characteristics among Medicare beneficiaries hospitalized with ischemic stroke.

BACKGROUND AND PURPOSE Get With The Guidelines (GWTG)-Stroke is a large quality improvement-based registry of acute stroke; however, its generalizability is unclear. We used fee-for-service Medicare claims to ascertain the representativeness of ischemic stroke admissions in GWTG-Stroke. METHODS All 228 815 ischemic stroke admissions aged ≥65 years enrolled in GWTG-Stroke between April 2003 and December 2007 were linked to 926 756 unique fee-for-service Medicare patients with ischemic stroke (primary International Classification of Diseases, 9th Revision discharge code 434 or 436) from the same period. Patient characteristics and in-hospital outcomes were compared between the linked GWTG-Stroke Medicare cohort and the remaining unlinked Medicare cohort. Characteristics of GWTG-Stroke hospitals were compared with non-GWTG-Stroke hospitals. RESULTS A total of 144 344 of the 228,815 GWTG-Stroke admissions (63.1%) were successfully linked to the 926 756 Medicare ischemic stroke beneficiaries, leaving 782 412 unlinked Medicare patients. Differences in patient characteristics, including age, race, gender, and comorbidities, between the linked and unlinked Medicare cohorts were minimal. Length of stay and rate of discharge home were almost identical between the linked and unlinked groups; however, in-hospital mortality was slightly lower in the linked Medicare cohort (6.3%) compared with the unlinked cohort (7.0%). There were large differences in hospital characteristics between GWTG-Stroke and non-GWTG-Stroke hospitals; GWTG-Stroke hospitals tended to be larger, urban, teaching centers. CONCLUSIONS Despite substantial differences between GWTG-Stroke and non-GWTG-Stroke hospitals, Medicare beneficiaries with acute ischemic stroke entered in the GWTG-Stroke program were similar to other Medicare beneficiaries. These data suggest that the Medicare-aged GWTG-Stroke ischemic stroke admissions are generally representative of the national fee-for-service Medicare ischemic stroke population.