Can physician laboratory-test requests be influenced by interventions?

Background: Laboratory tests affect healthcare costs and unnecessary test requests can thus be a concern. We studied whether it was possible to influence physician laboratory-test requests using four structured interventions: introduction of clinical guidelines, education, feedback, and reminder letters. The interventions occurred at different times at Landspítali University Hospital, Reykjavik, Iceland. Akureyri Hospital, northern Iceland, was used as a control, since no formal interventions were introduced there.

Materials And Methods: Six types of laboratory tests were analyzed. The relative risk of a laboratory test being conducted at Landspítali University Hospital compared to Akureyri Hospital was calculated for various points in time, as well as the associated 95% confidence intervals. The primary estimates compare the pre- and post-intervention periods (2007-2009 vs. 2010-2013), but also on a monthly basis in order to observe the trends in greater detail.

Results: Interventions at Landspítali University Hospital led to a significant reduction in the average number of laboratory tests (12-52%, p < 0.001) compared with Akureyri Hospital. Relative risk coefficients of laboratory tests at Landspítali University Hospital (LUH) compared to Akureyri Hospital (AH) were calculated pre- and post-guidelines, the relative risk for ASAT, CRP and GGT fell markedly, while ALAT and ALP tests did not show a significant decrease. Relative risk for a blood culture test in the period after the guidelines was statistically significantly increased.

Conclusion: It is possible to influence physician laboratory-test requests using multifaceted interventions that include continuous monitoring and follow-up.