Impact of Interventions to Change CBC and Differential Ordering Patterns in the Emergency Department

Objectives: A CBC with leukocyte differential (CBC-DIFF) is a frequently ordered emergency department (ED) test. The DIFF component often does not add to clinical decision making. Our objective was to evaluate the impact of a performance improvement project on CBC ordering. Methods: ED orders for CBC-DIFF were identified through the laboratory information system. Two interventions were evaluated: an educational intervention regarding CBC-DIFF uses and a reprioritization of ED CBC-DIFF and CBC in the electronic medical record (EMR) orders. Pearson χ2 tests were used to assess for differences in the proportions. Results: There was no difference in the proportion of CBC tests performed after the education intervention (175/6,192, 2.8% [95% CI, 2.39%-3.21%] vs 219/6,270, 3.5% [95% CI, 3.05%-3.95%]). There was a significant increase in CBC samples ordered following the EMR intervention (604/6,044, 9.1% [95% CI, 8.37%-9.83%]; P < .01). Conclusions: Reprioritizing EMR laboratory orders can reduce overutilization of CBC-DIFF testing.