Appropriate Testing in an Era of Limited Resources


Chapter 5
Appropriate Testing in an Era of Limited Resources: Practice and Policy Considerations


Fernanda Bellolio1 and Christopher R. Carpenter2


1 Department of Emergency Medicine, Mayo Clinic, Rochester, MN, USA


2 Department of Emergency Medicine, Washington University School of Medicine, St. Louis, MO, USA


This chapter will focus on the United States, which spends more on health care than any other country. In 2016, the United States spent 18% of its gross domestic product (GDP) on health care, while spending in other high‐income nations were 9.6% in Australia, 10.3% in Canada, 10.9% in Japan, and 12.4% in Switzerland.1 Despite the highest spending, the United States has the lowest proportion of the population with health insurance at 90% compared to other high‐income countries at 99.8–100%.1


Papanicolas et al. report that this spending was not associated with improved population health care outcomes, and contrary to some explanations for high spending, social spending, and health care utilization in the United States does not differ substantially from other high‐income nations. Pharmaceuticals, devices, and administrative costs appeared to be the main drivers of the differences in spending. Specifically, administrative costs of care including scheduling, planning, regulating, and managing health systems and services accounted for 8% in the United States versus a range of 1–3% in the other countries. For pharmaceutical costs, spending per capita was $1443 in the United States compared to a range of $466–$939 in other countries.1


Understanding medical expenditures within the context of healthcare resource stewardship and sustainable spending has increased the focus on eliminating low‐value care and reducing waste.2 Proposed solutions include single‐payer systems,3 payment reform (including accountable care organizations, bundled payments, and value‐based care instead of volume‐based), and more reliably effective care delivery (including care coordination, decreased physician variability in care, at‐home medical care, and partnership for patients U.S. Center for Medicare and Medicaid Services [CMS]‐initiative).4 We have created a very complex medical system, and there has been an attempt to reduce the time the physician spends in issues related to insurance, reporting to quality agencies, and medical billing‐related paperwork.5, 6 As an example, there has been an increase in the use of medical scribes to help the administrative tasks of documentation during the medical visit, or use of intermediaries to navigate medical records. Strategies to improve physician efficiency and the increasing administrative demands have been associated with increased rates of physician burnout.7


Shrank et al.4 identified six waste domains including failure of care delivery, failure of care coordination, overtreatment or low‐value care, pricing failure, fraud and abuse, and administrative complexity. A call for evidence‐based strategies to reduce waste has been proposed. In this context, emergency departments (EDs) play a central role in US healthcare delivery, with 130 million visits in 2018.8 Increases in ED visit rates have outpaced population growth, until recently with lower visits related to the coronavirus disease (COVID‐19) pandemic. Yet, there has been an increase in intensity of care which means more extensive, costly, and time consuming workup including diagnostic imaging and laboratory tests, causing ED overcrowding.9 ED care is often fragmented and more costly than in other settings; as a result, EDs are a target for reforms. The adoption of alternative payment models to improve patient outcomes and reduce costs have been proposed. Accountable care organizations and other financial risk‐bearing entities primarily focus on reducing ED visits rather than engaging with EDs improving quality of care delivery.9


What role does physician decision‐making around the use of diagnostic tests play in the debate around the rising cost of healthcare? Diagnostic testing makes up a significant and growing proportion of national healthcare expenditures. When ordered appropriately, diagnostic tests, such as computed tomography (CT) for abdominal pain, can help reduce resource use by identifying patients who do not need hospitalization or further interventions. Yet, in our search for certainty, we sometimes order tests that are unlikely to affect our medical decision‐making. Many tests add no information and do not affect decision‐making (e.g., “routine bloodwork” for the adult with gastroenteritis). Worse yet, out of tradition, habit, the request of other services, or lack of access to previous results, we repeat tests that have been recently performed and are unlikely to have changed.10, 11 Diagnostic tests that do not add useful information are a clear form of medical waste – directly visible to and controllable by clinicians. Less visible to emergency clinicians, but more important from a cost perspective, are the downstream costs of diagnostic testing. Unnecessary tests could also yield false‐positive results requiring follow‐up tests or treatments to ensure the patient does not have conditions not initially suspected, for example an elevated potassium may reflect a hemolyzed sample. Despite the overwhelming evidence that many diagnostic tests are of little or no value, changing practice is difficult. For example, routine preoperative testing of healthy adults is the norm across the United States despite strong evidence that it provides no value.12, 13 We believe that improving the appropriateness of diagnostic testing is one way that medical professionals can reduce costs and improve value, as it can be done while improving the quality of patient care. Unfortunately, to date, many physicians have shown little interest or ability to do this. This is our challenge – apply the best evidence at the bedside and build systems to support us, before insurance and government regulators build them for us.


In this chapter, we discuss the role of diagnostic testing on healthcare costs, identify practice changes that physicians can implement to help improve the appropriateness of testing, and discuss policy approaches to reducing the use of testing.


Impact of diagnostic testing on healthcare expenditures


Healthcare spending is rising across the world at rates above the rate of economic growth or the willingness of societies to increase taxation. The US national healthcare spending in 2019 was $3.8 trillion, or $11,582 per person, accounting for 17.7% of GDP.14


As healthcare is the single largest component of current and future deficit spending, rising costs are leading to political conflict and gridlock affecting many other areas. At the individual level, as healthcare costs rise, fewer people have access to care and more people suffer when they get sick, due to events such as medical bankruptcy.15 In this environment, healthcare providers should expect stable or shrinking resources and significant pressure to cut costs. If providers do not lead with solutions, politicians and businesses will be forced to implement controls. Political solutions to rising costs are unlikely to reflect the best available scientific evidence.


Diagnostic testing accounts for a significant and rising proportion of national health expenditures. Exact calculations of spending on diagnostic testing are difficult, as testing can appear in several different categories of health expenditures (e.g., hospital care, physician services, and other professional services) and is sometimes bundled with other costs, such as during hospitalization. The cost of diagnostic imaging has risen dramatically over the years. Spending on the physician services associated with imaging, just one component of imaging costs was $10.4 billion in 2018.16 The US imaging services market size was valued at $128.1 billion in 2019 and is anticipated to grow at a compound annual growth rate (CAGR) of 4.6% from 2020 to 2027.17


Imaging has been argued to be cost‐effective in reducing hospital admissions and invasive procedures, and therefore has the potential to reduce total healthcare costs. Interestingly, some studies have found that providers that perform more tests and use more ED resources are also more likely to admit patients,18 and one study reported no significant test‐ordering differences between ED physicians versus advanced practice providers caring for patients with chest pain or abdominal pain.19


Downstream costs of diagnostic testing


As a proportion of diagnostic tests are inappropriate and potentially avoidable, there is great potential to reduce the direct cost of diagnostic testing. Equally important as the direct costs of diagnostic tests are the downstream costs associated with incidental findings on unnecessary tests. While we should order diagnostic tests to answer a specific question, the results sometimes do not answer the question specifically. Instead, they provide a range of information that can influence the probability of disease and help with risk stratification. They may also provide additional information to other questions that we did not wish to ask. A false‐positive test result may not be in concordance with the rest of our thinking, yet still requires further downstream workup. For example, consider a patient admitted to the hospital from the ED with community‐acquired pneumonia and blood cultures that yield Gram‐positive cocci in clusters, ultimately revealing Staphylococcus aureus. The blood culture may generate downstream testing such as repeat blood cultures and an echocardiogram. Studies have estimated that false‐positive blood cultures add tens of thousands of dollars to the overall hospital costs.20 Additionally, the diagnostic test may give answers to questions we did not wish to ask. For example, when ordering a pulmonary angiogram CT to evaluate a patient for pulmonary embolism, the scan will often reveal incidental findings in the thorax and upper abdomen such as pulmonary nodules or renal masses. Standard medical practice requires appropriate follow‐up for these incidental findings, which usually involves repeat imaging and may require biopsies and eventual treatment. Thus, indirect costs of the original test include workup and treatment of false positives and incidental findings.


Variation in testing and inappropriate testing


There is evidence that a significant proportion of diagnostic tests performed in the United States are potentially avoidable based on the patient’s clinical condition and the best available evidence.21 One way to look at this is to look at the indications for specific tests. Retrospective studies of diagnostic test services show that a significant proportion of diagnostic tests do not have evidence to support their use in the patient. Studies of geographic variation also illustrate this.22 For example, patients in some areas of the United States are more likely to undergo cardiac catheterization for stable angina or after an acute myocardial infarction (MI) than patients in other regions, regardless of the appropriateness of the procedure. Similar patterns have been shown with the use of laboratory tests and other diagnostic tests like magnetic resonance imaging (MRI), CT, and cardiac stress test.23 Such variation also exists within hospitals, departments, and practices, even after adjustment for a patient’s clinical condition and comorbidities. Such variation is reasonable for some diagnostic tests where there is little definitive evidence, such as abdominal CT for undifferentiated abdominal pain. It is hard to justify for conditions that have been well studied and for which validated clinical decision rules are available, such as ankle X‐rays (Chapter 12) or D‐dimer for pulmonary embolism24 (Chapter 52).


There are variations in testing not explained by variations in practice or hospital settings, for example within the same institution some clinicians will test more than others.25 Variations in testing are also dependent on the population or area of practice. EDs represent a safety net for several patients without access to primary care or outpatient clinics. Some patients who could be eligible for a conservative (e.g., wait and watch) approach might not have the opportunity to seek or access outpatient care. Also penalizing providers for patients’ return visits to the ED might increase the desire for diagnostic certainty with the idea of reducing such returns. Having primary care access has been demonstrated to influence the rate of imaging. In one study, the rate of CT utilization was higher among patients without a primary care physician compared to those that had access to outpatient primary care.26 Increased availability of primary care, particularly for follow‐up from the ED, could reduce ED resource utilization and therefore decrease costs, ED lengths of stay, and radiation exposure.


Causes of inappropriate testing


Inappropriate use of diagnostic tests can be classified into the categories of underuse, overuse, and misuse. Underuse refers to the failure to provide a healthcare service when there is evidence that it would have produced a favorable outcome for the patient, like delay in diagnosis or treatment. Overuse occurs when a test or treatment is used without medical justification – a diagnostic test without evidence to support its use in the condition, patient, or setting. Misuse of preference‐sensitive care refers to situations in which there are significant trade‐offs among the available options (such as the choice between CT and observation in a young woman with an atypical presentation for early appendicitis). Choices should be based on the patient’s own values, but often they are not.27 Misuse results from the failure to accurately communicate the alternative’s risks and benefits, and the failure to base the choice of diagnostic test on the patient’s values and preferences. In this chapter, we focus on overuse and misuse of diagnostic tests, as they are an important focus in the ongoing discussion of cost control in healthcare. In Chapter 60 we discuss shared decision‐making with examples of cases of equipoise and balance of available evidence and patients’ values and preferences. Table 5.1 illustrates the types of overuse and misuse of diagnostic testing.


The overuse of diagnostic tests in the United States is multifactorial, and an important culprit is the quest for diagnostic certainty. Clinicians give many reasons why they order diagnostic tests that they acknowledge have little or no value, including fear of missing diagnoses (defensive medicine), avoiding diagnostic errors, lack of clear guidelines on the specific encounter, lack of awareness or adoption of clinical decision rules, lack of awareness of the cost, patient’s requests, other physicians or consulting services’ requests, increased complexity of emergency care, and incentives to decrease hospital admissions.30, 31 Additionally, there are financial incentives to encourage inappropriate testing, such as the fee‐for‐service medical system. Specifically, in emergency medicine in the United States, physician reimbursement is determined by the complexity of the visit. Ordering and interpretation of diagnostic tests are key determinants of complexity. For example, evaluating a patient with a mild traumatic head injury by routinely ordering a CT will generate a larger bill than using a clinical decision rule and not ordering a CT. While each of these plays a role in over‐ordering diagnostic tests, none is as important as our cultural search for medical certainty. According to Sir William Osler, medicine at its heart is an art and science of uncertainty.


Table 5.1 Categories of misuse and overuse of diagnostic testing in emergency medicine






































Category Rationale Examples
Bad test Evidence does not support the use of the diagnostic test for the clinical indication

  • Erythrocyte sedimentation rate (ESR) and C‐reactive protein (CRP) to evaluate for septic arthritis28


  • Abdominal X‐rays (KUB) for abdominal pain
Good test but wrong patient Evidence does not support the use of the diagnostic test in the patient population

  • Blood culture for non‐critically ill cases of community‐acquired pneumonia


  • X‐ray for atraumatic low back pain without red flags


  • D‐dimer for patients at very low clinical risk of pulmonary embolism (PERC rule negative)
Good test but wrong time or setting Evidence does not support the use of the diagnostic test at the time of the encounter

  • Lyme disease serology testing at the time of tick identification and removal


  • Screening labs for a patient with known psychiatric disease presenting with symptom exacerbation29
Lack of additive information in context to other tests being ordered The test does not add information beyond other tests being performed

  • Creatinine kinase in addition to troponin to evaluate for acute myocardial infarction (MI) (excluding recent MI)


  • Amylase in addition to lipase to evaluate for pancreatitis
Misuse of diagnostic test The test is not appropriate based on available alternatives and the patient’s preferences

  • Routine use of CT abdomen and pelvis in young women with early presentation of right lower quadrant pain that could be early appendicitis, when ultrasound or observation is preferred

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May 14, 2023 | Posted by in Uncategorized | Comments Off on Appropriate Testing in an Era of Limited Resources

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