Reducing Laboratory Total Turnaround Time (TAT) using system dynamics simulation: Chemistry analyzer application

Abstract

Laboratory Total Turnaround Time (TAT) is the total time taken in the laboratory to analyze the samples. The objective of this work is to reduce TAT for the chemistry analyzer. The primary causes for delay and the causal relationships between all possible variables that affect the analyzing time process were identified. A model using system dynamic simulation for the process was built. A questionnaire was prepared to collect real values of the model variables; it covered 17 hospitals in Egypt and Sudan as samples of developing countries. The model key variables were: number of samples, staff number, number of devices, number of samples run at a time, and staff productivity. The system was tested by different scenarios using the collected real data. The results showed that TAT is directly proportional to the number of samples (an axiomatic result proves the success of the proposed model), and is inversely proportional to the rest of the key variables. The paper proposes a solution for reducing TAT through improving the staff productivity. When the productivity ranged between zero (unskilled new staff) and one (skilled new staff), TAT decreased from 299 minutes to 124 minutes on average respectively, which is nearly 41% reduction. This strategy is non costly since the lab skilled staff will train the new staff, a strategy that suites the low income countries.