The relative contribution of patient, provider and organizational influences to the appropriate diagnosis and management of diabetes mellitus.

Objective: To estimate the relative contribution of patient attributes, provider characteristics and organizational features of the doctors' workplace to the diagnosis and management of diabetes.

Research Design And Methods: In a factorial experimental design doctors (n = 192) viewed clinically authentic vignettes of 'patients' presenting with identical signs and symptoms. Doctor subjects were primary care doctors stratified according to gender and level of experience. During an in-person interview scheduled between real patients, doctors were asked how they would diagnosis and manage the vignette 'patients' in clinical practice.

Results: This study considered the relative contribution of patient, doctor and organizational factors. Taken together patient attributes explained only 4.4% of the variability in diabetes diagnosis. Doctor factors explained only 2.0%. The vast majority of the explained variance in diabetes diagnosis was due to organizational factors (14.3%). Relative contributions combined (patient, provider, organizational factors) explained only 20% of the total variance.

Conclusion: Attempts to reduce health care variations usually focus on the education/activation of patients, or increased training of doctors. Our findings suggest that shifting quality improvement efforts to the area which contributes most to the creation and amplification of variations (organizational influences) may produce better results in terms of reduced variations in health care associated with diabetes.