Do Physicians Do What They Say?: The Inclination to Test and Its Association with Coronary Angiography Rates

Abstract

OBJECTIVE:

Efforts to evaluate variations in cardiac procedures have focused on patient factors and differences in health care delivery systems. We wanted to assess how physicians' inclination to test patients with coronary artery disease influences utilization patterns.

SETTING AND SUBJECTS:

Physicians and the populations of Maine, New Hampshire, and Vermont.

DESIGN:

We conducted a survey of 263 family practitioners, internists, and cardiologists residing in 57 hospital service areas in Maine, New Hampshire, and Vermont. Using patient scenarios, we assessed the clinicians' inclinations to test during the evaluation of patients with coronary artery disease. Self-reported testing intensities were used to create three indices: a Catheterization Index, an Imaging Exercise Tolerance Test (ETT) Index, and a Nonimaging ETT Index. Using administrative data, age- and gender-adjusted population-based coronary angiography rates were calculated. Physicians were assigned to low (2.9/1,000), average (4.2/1,000), and high (5.8/1,000) coronary angiography rate areas, based on where they practice. Analysis of variance techniques were used to assess the relation of the index scores to the population-based coronary angiography rates and to physician specialties.

RESULTS:

There was a positive relationship between the population-based coronary angiography rates and the self-reported scores of the Catheterization Index (p < .005) and the Imaging ETT Index (p = .01), but none was found for the Nonimaging ETT Index (p = .10). These relationships were evident in subanalyses of cardiologists and internists, but not of family practitioners.

CONCLUSIONS:

Self-reported testing intensity by physicians is related to the population-based rates of coronary angiography. This relationship cuts across specialties, suggesting that there is a "medical signature" for the evaluation of patients with coronary artery disease.