Comparing the quality of antidepressant pharmacotherapy in the Department of Veterans Affairs and the private sector

Objective: Comparing quality of care between large health care systems is important for health systems management. This study compared measures of the quality of pharmacotherapy for patients with major depression across a sample of patients from the Department of Veterans Affairs (VA) and the private sector. Methods: In this observational study, all patients who were given a new prescription for an antidepressant and a diagnosis of major depression in the VA during fiscal year 2000 were identified by using administrative data (N=27,713). In the private sector, a similar sample of patients were identified by using Medstats MarketScan database (N=4,852). For both groups, measures of the quality of antidepressant pharmacotherapy were constructed. These measures were compared across the two groups by using logistic regression models. Controls for age, gender, comorbid disorders, and initial antidepressant drug prescribed were included in some models. Results: Although the populations had different demographic and clinical characteristics, differences in the quality measures between the two systems were few, with the VA slightly outperforming the private sector in the prescription of antidepressants during the acute phase of treatment, the first 84 days (84.7 compared with 81 percent) and during the maintenance phase of treatment, the first 181 days (53.9 compared with 50.9 percent). Patient characteristics that were associated with quality measures included being older, being female, and having a comorbid diagnosis of substance use disorder, bipolar disorder, or anxiety or adjustment disorder. Conclusions: Both systems had relatively high rates of adherence to pharmacotherapy guidelines. Even though the populations in the two systems were different, adjusting the analyses for clinical characteristics did little to change the measured differences between the two systems.