Evaluation of thyroid test utilization through analysis of population-level data

Multidisciplinary approach to redefining thyroid hormone reference intervals with big data analysis

OBJECTIVES

This study aimed to employ big data analysis to harmonize reference intervals (RI) for thyroid function tests, with refinement to the TSH upper reference limit, and to optimize the TSH reflex algorithm to improve clinical management and test utilization.

DESIGN & METHODS

TSH, free T4, and free T3 results tested in Alberta, Canada, on Roche Cobas and Siemens Atellica were extracted from the laboratory information system (N = 1,144,155 for TSH, N = 183,354 for free T4 and N = 92,632 for free T3). Results from specialists, inpatients, or repeat testing, as well as from positive thyroid disease, autoimmune disease, and pregnancy biomarkers were excluded. RIs were derived using statistical models (Bhattacharya, refineR, and simple non-parametric) followed by endocrinology and laboratory review.

RESULTS

The TSH RIs for 0 to 7 days, 8 days to 1 year, and ≥1 year were 1.23 to 25.0 mIU/L, 1.00 to 6.80 mIU/L and 0.20 to 6.50 mIU/L, respectively. The free T4 RIs for 0 to 14 days, 15 to 29 days, and ≥30 days were 13.5 to 50.0 pmol/L, 8.7 to 32.5 pmol/L, and 10.0 to 25.0 pmol/L, respectively. An updated TSH reflex algorithm was developed based on the optimized TSH and free T4 RIs, with free T4 reflexed only at a TSH of <0.1 mIU/L.

CONCLUSIONS

The collaboration of a multidisciplinary team and the utilization of big data analysis led to the enhancement of thyroid function RIs, specifically resulting in the widening of the upper TSH reference limit to 6.50. Application of these optimized RIs with the TSH reflex algorithm will serve as a guide for improvement in interpretation of thyroid function tests.

Optimizing the data in direct access testing: information technology to support an emerging care model

Direct access testing (DAT) is an emerging care model that provides on-demand laboratory services for certain preventative, diagnostic, and monitoring indications. Unlike conventional testing models where health care providers order tests and where sample collection is performed onsite at the clinic or laboratory, most interactions between DAT consumers and the laboratory are virtual. Tests are ordered and results delivered online, and specimens are frequently self-collected at home with virtual support. Thus, DAT depends on high-quality information technology (IT) tools and optimized data utilization to a greater degree than conventional laboratory testing. This review critically discusses the United States DAT landscape in relation to IT to highlight digital challenges and opportunities for consumers, health care systems, providers, and laboratories. DAT offers consumers increased autonomy over the testing experience, cost, and data sharing, but the current capacity to integrate DAT as a care option into the conventional patient-provider model is lacking and will require innovative approaches to accommodate. Likewise, both consumers and health care providers need transparent information about the quality of DAT laboratories and clinical decision support to optimize appropriate use of DAT as a part of comprehensive care. Interoperability barriers will require intentional approaches to integrating DAT-derived data into the electronic health records of health systems nationally. This includes ensuring the laboratory results are appropriately captured for downstream data analytic pipelines that are used to satisfy population health and research needs. Despite the data- and IT-related challenges for widespread incorporation of DAT into routine health care, DAT has the potential to improve health equity by providing versatile, discreet, and affordable testing options for patients who have been marginalized by the current limitations of health care delivery in the United States.

Promoting Choosing Wisely Thyroid Function Test Guidelines in a Large Pediatric Hospital System

BACKGROUND

Free thyroxine (fT4) is often ordered when not indicated. The goal of the current study was to use quality improvement tools to identify and implement an optimal approach to reduce inappropriate fT4 testing throughout a large pediatric hospital system.

METHODS

After reviewing evidence-based guidelines and best practices, a thyroid-stimulating hormone with reflex to fT4 test and an outpatient thyroid order panel with clinical decision support at order entry, along with several rounds of provider education and feedback, were implemented. Outpatient and inpatient order sets and system preference lists were reviewed with subject matter experts and revised when appropriate. Tracking metrics were identified. Automated monthly run charts and statistical process control charts were created using data retrieved from the electronic health record. Charts established baseline data, balancing measure data, monitored the impact of interventions, and identified future interventions.

RESULTS

Over a 44-month period, among nonendocrinology providers, a reduction in fT4 and thyroid-stimulating hormone co-orders from 67% to 15% and an increase in reflex fT4 tests from 0% to 77% was obtained in inpatient and outpatient settings. Direct cost savings as a result of performing 5179 fewer fT4 tests over 3 years was determined to be $45 800.

CONCLUSIONS

After implementation of a reflex fT4 test, a novel order panel with clinical decision support, provider education, and changes to ordering modes, a large and sustainable reduction in fT4 tests that was associated with significant cost savings was achieved among nonendocrinology providers.

Limited Utility of Free Triiodothyronine Testing

BACKGROUND

Free triiodothyronine (fT3) testing is most useful when thyroid stimulating hormone (TSH) is suppressed, and free thyroxine (fT4) is normal or decreased. These laboratory values in a symptomatic patient are referred to as T3 thyrotoxicosis. Standards for fT3 reflex testing have not been established. Herein, we examined the clinical utility of fT3 with the goal of identifying a TSH cutoff in the context of normal/decreased fT4 that maximizes the utility of measuring fT3.

METHODS

TSH, fT4, and fT3 results between January 2016 and October 2021 were extracted from the laboratory information system and grouped if resulted on the same day for the same patient. Frequency of biochemical T3 thyrotoxicosis was evaluated at different TSH cutoffs and in outpatient vs inpatient settings.

RESULTS

Of the 4366 TSH-fT4-fT3 results, 70 (1.6%) were consistent with biochemical T3 thyrotoxicosis. The common reasons were previously diagnosed hyperthyroidism on antithyroid medication (n = 28) or hypothyroidism on thyroid medication (n = 18) and newly diagnosed hyperthyroidism (n = 20, 0.5%). The likelihood of detecting T3 thyrotoxicosis increased with lower TSH cutoff (<0.3 μIU/mL, 10.3% vs <0.0 1μIU/mL, 27.6%). All patients with newly diagnosed hyperthyroidism had TSH <0.01 μIU/mL. Higher frequency of T3 thyrotoxicosis was observed in the outpatient setting (34%) relative to the inpatient setting (14%, P < 0.001) when TSH < 0.01 μIU/mL.

CONCLUSIONS

T3 thyrotoxicosis is a relatively rare diagnosis and fT3 measurement has limited utility in the vast majority of patients. A fT3 reflex for patients with TSH <0.01 μIU/mL and normal/low fT4 may improve clinical utility and reduce unnecessary testing, especially in the outpatient setting.

Patient Population and Test Utilization for Thyroid Function in Local Clinics and Hospitals in Korea

We evaluated the utilization and characteristics of thyroid function test (TFT) results, including serum thyroid stimulating hormone (TSH), free thyroxine (free T4), and total triiodothyronine (total T3) in Korean adults who visited local clinics and hospitals between 2018 and 2020. We obtained TFT results for 69,575 specimens from 47,685 adult Korean patients (4878 men and 42,807 women) with a mean age of 42.7 (standard deviation of 13.2) years. Among them, 23,581 specimens were tested for TSH only, 38,447 specimens were tested for TSH and free T4 (including 17,978 specimens without total T3), and 20,469 specimens were tested for all three, i.e., TSH, free T4, and total T3. The proportion of euthyroid was 80.0% among all 69,575 specimens, 71.2% among specimens with TSH and free T4, and 64.2% among specimens with all three TFTs. TFT patterns that were difficult to interpret and needed more clinical information were observed for about 6.9% of the 20,469 specimens with all three TFTs. Among the 20,469 specimens with all three TFTs, no specimen had increases in all three. Information on the prevalence of specimen results of TFTs would be helpful to expand our knowledge of patient population characteristics and to improve test utilization.

Inappropriate use of clinical practices in Canada: a systematic review

Background:

Inappropriate health care leads to negative patient experiences, poor health outcomes and inefficient use of resources. We aimed to conduct a systematic review of inappropriately used clinical practices in Canada.

Methods:

We searched multiple bibliometric databases and grey literature to identify inappropriately used clinical practices in Canada between 2007 and 2021. Two team members independently screened citations, extracted data and assessed methodological quality. Findings were synthesized in 2 categories: diagnostics and therapeutics. We reported ranges of proportions of inappropriate use for all practices. Medians and interquartile ranges (IQRs), based on the percentage of patients not receiving recommended practices (underuse) or receiving practices not recommended (overuse), were calculated. All statistics are at the study summary level.

Results:

We included 174 studies, representing 228 clinical practices and 28 900 762 patients. The median proportion of inappropriate care, as assessed in the studies, was 30.0% (IQR 12.0%–56.6%). Underuse (median 43.9%, IQR 23.8%–66.3%) was more frequent than overuse (median 13.6%, IQR 3.2%–30.7%). The most frequently investigated diagnostics were glycated hemoglobin (underused, range 18.0%–85.7%, n = 9) and thyroid-stimulating hormone (overused, range 3.0%–35.1%, n = 5). The most frequently investigated therapeutics were statin medications (underused, range 18.5%–71.0%, n = 6) and potentially inappropriate medications (overused, range 13.5%–97.3%, n = 9).

Interpretation:

We have provided a summary of inappropriately used clinical practices in Canadian health care systems. Our findings can be used to support health care professionals and quality agencies to improve patient care and safety in Canada.

Routine T4 No More? Reducing Excess Thyroid Hormone Testing at a Pediatric Tertiary Care Hospital

OBJECTIVES

To promote resource stewardship in thyroid hormone testing at a pediatric tertiary care hospital.

STUDY DESIGN

Quality improvement approaches generated 3 change ideas that were implemented simultaneously in the hospital electronic medical record: (1) a reflex free thyroxine (fT4), whereby fT4 is automatically reported if the thyroid-stimulating hormone is outside the normal range; (2) a forced-function for thyroid hormone ordering, whereby a provider must select an appropriate indication for ordering fT4 or triiodothyronine (T3); and (3) a clinical decision support message displayed at the time of ordering thyroid function tests. Laboratory data were audited to determine the mean number of fT4 and T3 tests performed per week as well as indications for testing.

RESULTS

The mean number of fT4 and T3 tests processed per week decreased from 154 ± 21 and 11 ± 7, respectively, in the preintervention period, to 107 ± 12 (30% reduction) and 4 ± 3 (66% reduction) postintervention. These reductions were sustained for the full 20-week assessment period. Process and balancing measures revealed no unintended adverse consequences. Approximate cost savings were $43 000 per year.

CONCLUSIONS

We describe the successful implementation of electronic medical record-based interventions (reflex fT4, forced-function selection of indication, decision support text) leading to sustained improvements in healthcare use, with significant associated cost-savings.

Laboratory Demand Management Strategies-An Overview

Inappropriate laboratory test selection in the form of overutilization as well as underutilization frequently occurs despite available guidelines. There is broad approval among laboratory specialists as well as clinicians that demand management strategies are useful tools to avoid this issue. Most of these tools are based on automated algorithms or other types of machine learning. This review summarizes the available demand management strategies that may be adopted to local settings. We believe that artificial intelligence may help to further improve these available tools.

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

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.