APPROPRIATENESS OF IMAGING PROCEDURE REQUESTS - DO RADIOLOGISTS AGREE

OBJECTIVE. We explored the agreement among radiologists in their evalu ation of the appropriateness of individual requests for imaging proced ures. MATERIALS AND METHODS. We reviewed 318 noninterventional CT, son ographic, MR imaging, and nuclear medicine procedures ordered at a gen eral internal medicine clinic during 8 months in 1995, Five subspecial ty radiologists used data from the radiology request form and clinic n otes to independently rate the appropriateness of each requested imagi ng procedure on a four-point scale. The radiologists were unaware of t he results achieved by each procedure. Each case was reviewed by at le ast three radiologists, of whom at least one had relevant subspecialty expertise. Agreement among radiologists was analyzed using Cohen's ka ppa statistic and weighted kappa statistics and Cronbach's alpha stati stic. RESULTS. Nonchance agreement (kappa) was .19 +/- .05; weighted k appa was .24 +/- .05. Interrater agreement was significantly greater t han that expected from chance alone (p < .01). The composite score, de fined as the average of the radiologists' scores for each case, showed moderate reliability, as evidenced by a value for Cronbach's alpha of .70. CONCLUSION. In the absence of explicit criteria, we found modest but statistically significant agreement among radiologists about the appropriateness of individual requests for imaging procedures. The dis agreement among radiologists highlights the importance of developing w ell-reasoned, explicit criteria by which to judge the appropriateness of diagnostic radiology procedures. Further study is needed to elucida te the relationship between appropriateness and actual patient outcome s.