Large-Scale Analysis Evaluating Regional Variability in the Request of Laboratory Tests in Primary Care and its Potential Economic Impact.

Objective: To compare the ratios of requests of aspartate aminotransferase (AST) to alanine aminotransferase (ALT) and urea to creatinine (Crea); to investigate the variability among regions and to calculate the potential savings if a target is reached.

Methods: Laboratories were invited to fill out a registration form on the number of AST, ALT, Urea and Crea requested in 2014, and to provide the reagent price of urea and AST. AST:ALT and Urea:Crea were calculated and compared; also compared were potential savings if each laboratory would have reached the target. Results: A significant difference was found among regions in Urea:Crea. Twenty-one laboratories reached the goal in AST:ALT, and 6 in Urea:Crea. The potential savings if each indicator would have reached the target would have been $553,827 and $745,184, respectively.

Conclusion: Variability was found in AST:ALT and Urea:Crea, which resulted in a significant unnecessary financial burden and suggests the need to promote the optimal requesting rate.