Survey nonresponders incurred higher medical utilization and lower medication adherence.

OBJECTIVES

To compare healthcare costs, utilization, and medication adherence between diabetic responders and nonresponders to a patient satisfaction survey.

STUDY DESIGN

We performed a retrospective cohort study of 40,766 patients with diabetes who had been randomly selected to receive the 2006 Veterans Affairs' Survey of Healthcare Experiences of Patients. Outcomes were measured during the following year.

METHODS

We used multivariable models to compare healthcare costs (generalized linear models), utilization (negative binomial regression), and adherence to oral hypoglycemic medications (logistic regression) between survey responders and nonresponders.

RESULTS

There were 26,051 patients (64%) who responded to the survey. Survey nonresponders incurred significantly higher healthcare costs (incremental effect, $792; 95% CI, $599-$986; P < .01). Nonresponders had a modest increase in primary care (incidence rate ratio [IRR], 1.06; 95% CI, 1.05-1.08; P < .01) and specialty care visits (IRR, 1.17; 95% CI, 1.12-1.22; P < .01), but more substantial increases in mental health visits (IRR, 1.74; 95% CI, 1.62-1.87; P < .01) and hospitalizations (IRR, 1.60; 95% CI, 1.46-1.75; P < .01). Medication adherence was significantly lower among survey nonresponders (odds ratio, 0.68; 95% CI, 0.65-0.74; P < .01).

CONCLUSIONS

Nonresponders to a patient satisfaction survey incurred higher healthcare costs and utilization, but had lower medication adherence. Understanding these characteristics helps to assess the impact of nonresponse bias on patient satisfaction surveys and identifies clinical practices to improve care delivery.