Reducing free thyroid hormone testing through multiple Plan-Do-Study-Act cycles.

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OBJECTIVES: Free thyroid hormones (fT4 and fT3) are one of the most commonly ordered laboratory tests and often ordered when not clinically meaningful. Based on this, many studies have sought to identify strategies to reduce inappropriate fT4 and fT3 testing. The goal of the current study was to implement a quality improvement (QI) framework to identify an optimal approach to reducing inappropriate free thyroid hormone testing through multiple change ideas and Plan-Do-Study-Act (PDSA) cycles. The aim was to reduce fT4 and fT3 30% from baseline at a large tertiary hospital within 12 months.

METHODS: The Model for Improvement Framework was used to implement a total of 3 change ideas in the first and second PDSA cycles. Change ideas included implementation and refinement of a free thyroid hormone forced function reflex system, modifications to test requisitions/order-entry interfaces, and a TSH-only option. Process and balancing measures were evaluated to fine-tune the change interventions. Data was continuously monitored pre and post interventions to assess progress, impact and potential errors.

RESULTS: In the first PDSA cycle, laboratory testing of fT4 was decreased by 24% and fT3 by 18%. Soliciting physician feedback and assessing balancing measures was important in refining the approach. In the second PDSA cycle, fT4 was decreased by an additional 16% and fT3 by 29%. An audit of the process showed that phone calls to the laboratory to add-on free thyroid hormones did not increase after the second PDSA, averaging 2 calls per month.

CONCLUSIONS: To achieve optimal reductions in free thyroid hormone testing, multiple PDSA cycles were required alongside assessing process and balancing measures. Overall, fT4 and fT3 testing was decreased by 39% and 47%, respectively.



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Medicine and Health Sciences




Department of Pathology and Laboratory Medicine

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