Volume 43 | Number 3 | June 2008

Abstract List

Christopher L. Sistrom, Niccie L. McKay


This study examines the relationship between evidence‐based appropriateness criteria for neurologic imaging procedures and Medicare payment determinations. The primary research question is whether Medicare is more likely to pay for imaging procedures as the level of appropriateness increases.

Data Sources

The American College of Radiology Appropriateness Criteria (ACRAC) for neurological imaging, ICD‐9‐CM codes, CPT codes, and payment determinations by the Medicare Part B carrier for Florida and Connecticut.

Study Design

Cross‐sectional study of appropriateness criteria and Medicare Part B payment policy for neurological imaging. In addition to descriptive and bivariate statistics, multivariate logistic regression on payment determination (yes or no) was performed.

Data Collection Methods

The American College of Radiology Appropriateness Criteria (ACRAC) documents specific to neurological imaging, ICD‐9‐CM codes, and CPT codes were used to create 2,510 medical condition/imaging procedure combinations, with associated appropriateness scores (coded as low/middle/high).

Principal Findings

As the level of appropriateness increased, more medical condition/imaging procedure combinations were payable (low = 61 percent, middle = 70 percent, and high = 74 percent). Logistic regression indicated that the odds of a medical condition/imaging procedure combination with a middle level of appropriateness being payable was 48 percent higher than for an otherwise similar combination with a low appropriateness score (95 percent CI on odds ratio=1.19–1.84). The odds ratio for being payable between high and low levels of appropriateness was 2.25 (95 percent CI: 1.66–3.04).


Medicare could improve its payment determinations by taking advantage of existing clinical guidelines, appropriateness criteria, and other authoritative resources for evidence‐based practice. Such an approach would give providers a financial incentive that is aligned with best‐practice medicine. In particular, Medicare should review and update its payment policies to reflect current information on the appropriateness of alternative imaging procedures for the same medical condition.