Noninvasive imaging for the diagnosis of coronary artery disease: Focusingthe development of new diagnostic technology

Background: New tests, such as magnetic resonance imaging (MRI) and electro n-beam computed tomography (CT), are being developed for the diagnosis of c oronary artery disease. Objective: To determine the conditions that a new test must meet to be a co st-effective alternative to established imaging tests. Design: Decision model and cost-effectiveness analysis. Data Sources: Literature review and meta-analysis. Target Population: 55-year-old men and 65-year-old women presenting with ch est pain. Time Horizon: Lifetime of the patient. Perspective: Health care policy. Interventions: MRI, electron-beam CT, exercise echocardiography, exercise s ingle-photon emission CT, and coronary angiography. Outcome Measures: Target sensitivity and specificity values for a new nonin vasive test. Results of Base-Case Analysis: Assuming that society is willing to pay $75 000 per quality-adjusted life-year (QALY) gained, a new test that costs $10 00 would need a sensitivity of 94% and a specificity of 90% to be cost-effe ctive. Results of Sensitivity Analysis: Assuming that society is willing to pay $5 0 000 per QALY gained, a new test that costs $1000 or more would never be c ost-effective. For a test that costs $500, the sensitivity and specificity must each be 95%. Conclusions: New imaging techniques, such as MRI and electron-beam CT, must be relatively inexpensive and have excellent sensitivity and specificity t o be cost-effective compared with other techniques for the diagnosis of cor onary artery disease. Similar analyses in other areas of health care may he lp to focus the development of new diagnostic technology.