Utility of the reference change value in defining the minimum interval between tests.

Abstract

According to expert guidelines, the minimum interval between requests for a liver panel is 48-72 hours. The reference change value is a parameter that indicates a significant variation in the result compared to the previous one. Objectives: To use the reference change value to analyze differences in liver panel results 24 and 48 hours after the initial measurement, and to analyze changes in turnaround time after implementing the rejection rule based on the agreed-upon interval between requests. Materials and methods: The results of the liver panel and reference change value at 24 and 48 hours were analyzed in an observational and retrospective study. The turnaround time of clinical chemistry results and the number of liver panel tests requested and performed were evaluated before and after the implementation of the rejection rule. Results: The odds of having a variation in the result above the reference change value at 48 hours was 9 and 8 times higher than that at 24 hours for total proteins (p<0.05) and alanine aminotransferase (p<0.05), respectively. No association was observed in the rest of the parameters, and no significant changes were found in the values measured. After implementing the rejection rule, there was a significant decrease in the turnaround time of clinical chemistry results (p<0.0001) and the number of liver panel tests performed (p<0.05). Conclusion: Through the innovative utilization of the reference change value, we successfully standardized the interval between requests to 48 hours, thereby demonstrating its validity. This strategic implementation led to cost reduction and improved turnaround time for result delivery, effectively optimizing resource utilization.