[Differences between hospitals in outcome after a stroke are only partially explained by differences in the quality...

To determine the extent to which the outcome of stroke patients stroke is correlated with patient characteristics and care process parameters, and to determine whether outcome measures can be used to measure the quality of hospital care provided for these patients.

Descriptive cohort study.

At 10 hospitals in the Netherlands, in the period October 2002-April 2003, patients with acute stroke were included in the study. Poor outcome was defined as dead or disabled at 1 year (a score on the modified Rankin scale > or = 3). Quality of the care was assessed by relating diagnostic, therapeutic and preventive procedures to indication. Multiple logistic regression models were used to compare observed numbers of patients with a poor outcome with expected numbers per hospital, after adjustment for patient characteristics and quality of care parameters.

In total, 579 patients were included in the study, of which 271 (47%) were dead or disabled at 1 year. Poor outcome varied across the hospitals from 29 to 78%. The mean age was 70 years. There were large differences between hospitals with respect to patient characteristics and quality of care. Most of the differences in outcome between hospitals were explained by the differences in patient characteristics (Akaike's information criterion (AIC) = 134). Quality of care parameters explained just a small additional part of the variation in patient outcome (AIC = 5.5).

Large differences between Dutch hospitals in the patient outcome after stroke could mostly be explained by differences in patient characteristics. Only a small part of the hospital variation in patient outcome was related to differences in quality of care. Therefore, outcome indicators cannot be regarded as valid performance indicators for care following a stroke.