While measures of free T4 (fT4) and free T3 (fT3) have replaced previous measurements of total T4 and total T3 levels, they are only indicated in certain clinical instances. At Women’s College Hospital (WCH) in Toronto, 65% of fT4 and 59% of fT3 measurements were ordered in the setting of a normal TSH. This high proportion of “unnecessary” free thyroid hormone tests inspired the creation of a resource stewardship intervention aimed at reducing fT4/fT3
testing by 50% to promote high-value care.
Firstly, an educational program was rolled-out to engage and inform health care professionals of appropriate indications for free thyroid hormone testing. Secondly, a laboratory reflex-fT4 system was implemented, in which fT4 was only processed if the TSH was outside of the laboratory reference range or clinical justification was provided on the laboratory requisition; fT3 was only processed if justification was provided. Overall, free thyroid hormone testing was reduced by 54%, which was sustained over 6 months. The hospital has benefited from significant cost-savings, physician satisfaction has been high, and patient outcomes have not been adversely affected. The successes of this project have led to its expansion to other institutions in Toronto, including St. Michael’s Hospital (SMH) and University Health Network (UHN).
The Less is More with T3 & T4 toolkit contains the key ingredients of their approach.
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