Yearly Clinical Laboratory Test Expenditures for Different Medical Specialties in a Major Canadian City

Data-driven approach to identifying potential laboratory overuse in general internal medicine (GIM) inpatients

BACKGROUND

Reducing laboratory test overuse is important for high quality, patient-centred care. Identifying priorities to reduce low value testing remains a challenge.

OBJECTIVE

To develop a simple, data-driven approach to identify potential sources of laboratory overuse by combining the total cost, proportion of abnormal results and physician-level variation in use of laboratory tests.

DESIGN, SETTING AND PARTICIPANTS

A multicentre, retrospective study at three academic hospitals in Toronto, Canada. All general internal medicine (GIM) hospitalisations between 1 April 2010 and 31 October 2017.

RESULTS

There were 106 813 GIM hospitalisations during the study period, with median hospital length-of-stay of 4.6 days (IQR: 2.33-9.19). There were 21 tests which had a cumulative cost >US$15 400 at all three sites. The costliest test was plasma electrolytes (US$4 907 775), the test with the lowest proportion of abnormal results was red cell folate (0.2%) and the test with the greatest physician-level variation in use was antiphospholipid antibodies (coefficient of variation 3.08). The five tests with the highest cumulative rank based on greatest cost, lowest proportion of abnormal results and highest physician-level variation were: (1) lactate, (2) antiphospholipid antibodies, (3) magnesium, (4) troponin and (5) partial thromboplastin time. In addition, this method identified unique tests that may be a potential source of laboratory overuse at each hospital.

CONCLUSIONS

A simple multidimensional, data-driven approach combining cost, proportion of abnormal results and physician-level variation can inform interventions to reduce laboratory test overuse. Reducing low value laboratory testing is important to promote high value, patient-centred care.

Laboratory test ordering in inpatient hospitals: a systematic review on the effects and features of clinical decision support systems

Background

Studies have revealed inappropriate laboratory testing as a source of waste. This review aimed at evaluating the effects and features of CDSSs on physicians' appropriate laboratory test ordering in inpatient hospitals.

Method

Medline through PubMed, SCOPUS, Web of Science, and Cochrane were queried without any time period restriction. Studies using CDSSs as an intervention to improve laboratory test ordering as the primary aim were included. The study populations in the included studies were laboratory tests, physicians ordering laboratory tests, or the patients for whom laboratory tests were ordered. The included papers were evaluated for their outcomes related to the effect of CDSSs which were categorized based on the outcomes related to tests, physician, and patients. The primary outcome measures were the number and cost of the ordered laboratory tests. The instrument from The National Heart Lung and Blood Institute (NIH) was used to assess the quality of the included studies. Moreover, we applied a checklist for assessing the quality and features of the CDSSs presented in the included studies. A narrative synthesis was used to describe and compare the designs and the results of included studies.

Result

Sixteen studies met the inclusion criteria. Most studies were conducted based on a quasi-experimental design. The results showed improvement in laboratory test-related outcomes (e.g. proportion and cost of tests) and also physician-related outcomes (e.g. guideline adherence and orders cancellation). Patient-related outcomes (e.g. length of stay and mortality rate) were not well investigated in the included studies. In addition, the evidence about applying CDSS as a decision aid for interpreting laboratory results was rare.

Conclusion

CDSSs increase appropriate test ordering in hospitals through eliminating redundant test orders and enhancing evidence-based practice. Appropriate testing and cost saving were both affected by the CDSSs. However, the evidence is limited about the effects of laboratory test CDSSs on patient-related outcomes.

Who repeats more laboratory tests inappropriately? Surgeons versus physicians

BACKGROUND

Inappropriate repeat testing is an objectively measurable type of health service overutilization which may harm patients.

OBJECTIVE

To evaluate both the frequency and cost of inappropriate repeat testing in a tertiary hospital in terms of specialties.

METHODS

This cross-sectional study was conducted in a tertiary hospital. Laboratory results of 26 tests ordered between 1 July 2014 and 30 June 2017 were evaluated retrospectively. Test that were repeated earlier than the minimum re-test interval were accepted as inappropriate repeat testing. After analyzing the descriptive statistics, the cluster analysis method was used to determine whether groups were formed within specialties.

RESULTS

Specialties form two clusters were found: the first cluster included specialties mostly from surgical science and the second cluster included specialties mostly from medical science. It was found that the cluster that includes mostly surgical specialties repeats laboratory tests at a higher rate but causes a waste of less resources, whereas the cluster that includes mostly medical specialties repeats laboratory tests at a lower rate but causes a waste of more resources due to a higher volume of test orders.

CONCLUSION

Due to the high rates of inappropriate repeat testing, surgical specialties seem to be the first target of intervention strategies, but medical specialties, which account for a higher volume of inappropriate repeat testing and higher unnecessary cost, should be the primary target of intervention strategies.

Frequency of repeat antinuclear antibody testing in Ontario: a population-based descriptive study

BACKGROUND

Repeat antinuclear antibody (ANA) testing may be unnecessary, potentially harmful and costly. Our aim was to assess the frequency and correlates of repeat ANA testing in Ontario.

METHODS

We performed a retrospective descriptive study identifying ANA tests performed over 2008-2015 among adults within the Ontario Laboratories Information System. Our primary outcome was any ANA test performed within 1 year of a previous ANA test. Our secondary outcome was any repeat test after a previous positive result. Repeat testing overall (regardless of who performed the previous test) and repeat testing by the same provider who performed the previous test were determined separately. We assessed correlates of repeat testing (e.g., patient and physician characteristics) and of repeat testing after a positive result using separate logistic regression models by means of generalized estimating equations to account for clustering of repeat testing within patients and within physician practices.

RESULTS

In total, 587 357 ANA tests were performed in 437 966 patients over the study period, of which 126 322 (21.5%) gave a positive result and 164 913 (28.1%) were repeat tests. Family physicians ordered 358 422 tests (61.0%), and rheumatologists ordered 65 071 tests (11.1%). Of the repeat tests, 82 332 (49.9%) were ordered within 12 months of the previous test. Among the 73 961 repeat tests ordered by the same practitioner within 12 months, the previous test result was positive for 22 657 (30.6%). A higher proportion of rheumatologists than other physicians ordered repeat tests within 12 months (36.1% v. 11.3%). The most significant correlate of potentially redundant testing was testing among patients with suspected or confirmed connective tissue disease.

INTERPRETATION

Over a quarter of ANA tests in Ontario were repeat tests; rheumatologists were most likely to order repeat testing. Our findings may be useful to inform quality-improvement initiatives related to the appropriateness of ANA testing.

Evaluating practice variance among family physicians to identify targets for laboratory utilization management

BACKGROUND

There is widespread variation in testing practice among practitioners, however there has been no objective way to pinpoint target tests for utilization management. We propose to take advantage of inter-physician variance in clinical practice as a quantitative measure to generate lists of potentially misutilized tests.

METHODS

Testing frequencies from a database of clinical testing volumes for outpatients in Calgary, Canada, were obtained for the study period of 2016. For each chemistry, microbiology or hematology test, an arithmetic coefficient of variation (CV) was calculated from family physicians' ordering frequencies.

RESULTS

The mean CV for all 358 tests considered was 219% (95% CI 206-231%) with a range of 52-729%. The highest variance was observed for human T-lymphotropic virus antibody testing and several tests for heavy metal levels (mercury, copper, zinc and chromium). Among the 100 most commonly run tests, high variance was found for several endocrinology tests including cortisol.

CONCLUSIONS

The utility of ranking clinical tests by ordering variance presents a practical approach to evaluate relative variation in physician practice strategy and to identify potential areas of misutilization.

Estimated costs of 51 commonly ordered laboratory tests in Canada

INTRODUCTION

Test cost display has been shown to reduce inappropriate laboratory test ordering practices in the United States. Unfortunately, such a system is limited in the Canadian publically funded healthcare environment. Many Canadian physicians inaccurately estimate the cost of laboratory tests, which may contribute to mis-utilization. Here, we provide an estimated cost of over 50 commonly ordered laboratory tests in Canada as an educational tool for physicians.

METHODS

Test volume data was collected from Calgary Laboratory Services' Laboratory Information System in order to determine which laboratory and diagnostic tests are most commonly ordered in Calgary and its surrounding area. Reference median cost (RMC) of fifty one commonly ordered test was calculated by determining the price list of all-inclusive indirect costs from six different clinical laboratories across Canada.

RESULTS

Of the 51 laboratory tests included, the minimum RMC was $5 CAD (eg: albumin, calcium, urea), and the maximum RMC was $300 (surgical pathology report).

CONCLUSIONS

A caveat to the provided list of test costs is that it is only an estimate and may differ from what each individual clinical laboratories charges to third parties or for research purposes. However, this list can serve as an educational tool and raise awareness for Canadian physicians on the relative costs of laboratory tests.

Changes in pathology test ordering by early career general practitioners: a longitudinal study

OBJECTIVE

To assess the number of pathology tests ordered by general practice registrars during their first 18-24 months of clinical general practice.

DESIGN

Longitudinal analysis of ten rounds of data collection (2010-2014) for the Registrar Clinical Encounters in Training (ReCEnT) study, an ongoing, multicentre, cohort study of general practice registrars in Australia. The principal analysis employed negative binomial regression in a generalised estimating equations framework (to account for repeated measures on registrars).Setting, participants: General practice registrars in training posts with five of 17 general practice regional training providers in five Australian states. The registrar participation rate was 96.4%.

MAIN OUTCOME MEASURE

Number of pathology tests requested per consultation. The time unit for analysis was the registrar training term (the 6-month full-time equivalent component of clinical training); registrars contributed data for up to four training terms.

RESULTS

876 registrars contributed data for 114 584 consultations. The number of pathology tests requested increased by 11% (95% CI, 8-15%; P < 0.001) per training term.

CONCLUSIONS

Contrary to expectations, pathology test ordering by general practice registrars increased significantly during their first 2 years of clinical practice. This causes concerns about overtesting. As established general practitioners order fewer tests than registrars, test ordering may peak during late vocational training and early career practice. Registrars need support during this difficult period in the development of their clinical practice patterns.

Sociodemographic Correlates of Clinical Laboratory Test Expenditures in a Major Canadian City

OBJECTIVES

The increasing cost of clinical laboratory testing is a challenge in our health care system. This study aims to calculate the annual clinical laboratory test costs attributed to patients in a major Canadian city and to correlate them to their sociodemographic variables.

METHODS

Retrospective cohort study involving patients who received clinical chemistry, hematology, and microbiology tests in 2011 in Calgary, Canada (n = 610,409). Test volumes were obtained from a laboratory informatics database. Total expenditures per patient were calculated using estimated test costs and then combined with the 2011 Canadian Census Household Survey results to infer sociodemographic correlates.

RESULTS

While more women received laboratory testing (58.4%), men had slightly higher testing costs per capita. Except for Chinese, visible minority and Aboriginal populations had higher testing costs. There was an inverse correlation between testing cost and household income, and accordingly, higher costs were found in those without postsecondary education and the unemployed. Furthermore, hotspot mapping revealed the geographical distribution of patient test costs within the city.

CONCLUSIONS

There is variation in testing costs for patients among different sociodemographic variables.

Utilization Management in a Large Community Hospital

The utilization management of laboratory tests in a large community hospital is similar to academic and smaller community hospitals. There are numerous factors that influence laboratory utilization. Outside influences like hospitals buying physician practices, increasing numbers of hospitalists, and hospital consolidation will influence the number and complexity of the test menu that will need to be monitored for over and/or under utilization in the central laboratory and reference laboratory. CLIA’88 outlines the four test categories including point-of-care testing (waived) and provider-performed microscopy that need laboratory test utilization management. Incremental cost analysis is the most efficient method for evaluating utilization reduction cost savings. Economies of scale define reduced unit cost per test as test volume increases. Outreach programs in large community hospitals provide additional laboratory tests from non-patients in physician offices, nursing homes, and other hospitals. Disruptive innovations are changing the present paradigms in clinical diagnostics, like wearable sensors, MALDI-TOF, multiplex infectious disease panels, cell-free DNA, and others. Obsolete tests need to be universally defined and accepted by manufacturers, physicians, laboratories, and hospitals, to eliminate access to their reagents and testing platforms.

Mean Abnormal Result Rate: Proof of Concept of a New Metric for Benchmarking Selectivity in Laboratory Test Ordering

OBJECTIVES

There is a need to develop and validate new metrics to access the appropriateness of laboratory test requests.

METHODS

The mean abnormal result rate (MARR) is a proposed measure of ordering selectivity, the premise being that higher mean abnormal rates represent more selective test ordering. As a validation of this metric, we compared the abnormal rate of lab tests with the number of tests ordered on the same requisition. We hypothesized that requisitions with larger numbers of requested tests represent less selective test ordering and therefore would have a lower overall abnormal rate.

RESULTS

We examined 3,864,083 tests ordered on 451,895 requisitions and found that the MARR decreased from about 25% if one test was ordered to about 7% if nine or more tests were ordered, consistent with less selectivity when more tests were ordered. We then examined the MARR for community-based testing for 1,340 family physicians and found both a wide variation in MARR as well as an inverse relationship between the total tests ordered per year per physician and the physician-specific MARR.

CONCLUSIONS

The proposed metric represents a new utilization metric for benchmarking relative selectivity of test orders among physicians.

Canadian family physician knowledge and attitudes toward laboratory utilization management

OBJECTIVES

Mitigation of unnecessary and redundant laboratory testing is an important quality assurance priority for laboratories and represents an opportunity for cost savings in the health care system. Family physicians represent the largest utilizers of laboratory testing by a large margin. Engagement of family physicians is therefore key to any laboratory utilization management initiatives. Despite this, family physicians have been largely excluded from the planning and implementation of such initiatives. Our purposes were to (1) assess the importance of lab management issues to family physicians, and (2) attempt to define the types of initiatives most acceptable to family physicians.

DESIGN AND METHODS

We invited all Alberta family practice residents and practicing physicians to participate in a self-administered online electronic survey. Survey questions addressed the perceived importance of lab misutilization, prevalence of various types of misutilization, acceptability of specific approaches to quality control, and responsibility of various parties to address this issue.

RESULTS

Of 162 respondents, 95% considered lab misutilization to be either important or very important. Many physicians placed the responsibility for addressing lab misutilization issues on multiple parties, including patients, but most commonly the ordering physician (97%). Acceptability for common strategies for quality improvement in lab misutilization showed a wide range (35%-98%).

CONCLUSIONS

These responses could serve as a framework for laboratories to begin discussions on this important topic with primary care groups.