More Isn’t Better: How Diagnostic Stewardship is Redefining Test Utilization

Challenging over-testing culture and emphasizing the value of targeted, evidence-based testing 

In the world of patient care, situations arise daily where there is a desire to use an “everything but the kitchen sink” approach. A child presents to the pediatrician with respiratory disease or diarrhea while an anxious parent waits desperately for a diagnosis and better yet, a cure. A patient demands testing after a social media influencer recommends tests that they claim have identified the cause of their chronic illness. In some cases, the reasons may be more practical – such as a patient who, for various reasons, has a high risk of being lost to follow-up. Creating real, sustainable diagnostic stewardship programs requires an understanding of what physicians face in their daily interactions with patients.

How did we get here? 

In the social media age, the pressure on physicians has never been greater, with seemingly unlimited, and often unvetted, information at our fingertips. In addition to practicing good medicine, physicians now worry about reviews of their practice on popular online platforms. Technological advances, such as multiplex nucleic acid amplification tests, make it possible to test for dozens of organisms at a time (albeit at a high cost). With the growing availability of these tests, why not test for everything upfront? What’s the harm, right? The reality is that there are hidden consequences to over-testing. More testing won’t necessarily lead to better outcomes and in some cases, causes harm.

Clinical pitfalls

For many conditions such as a gastrointestinal or respiratory disease, professional guidelines exist which identify the appropriate patient population for testing based on evidence-based medicine. But what if your patient doesn’t fit these guidelines and still wants testing? Should we acquiesce in the spirit of “what does it hurt to try?”.  No test is perfect, and all tests carry risks of false positives or negatives. When a test is used outside of the intended patient population, those risks may be higher due to low pre-test probability, which is the likelihood that a patient has a specific disease based on things like signs and symptoms, prevalence in the population, and their medical history. False results come with consequences, such as unnecessary antibiotic use or treatments, unwarranted follow-up procedures, or emotional distress for the patient. Even if the test identifies the causative agent, the disease itself may be self-limiting with no treatment. An example of this is viral diarrhea, such as norovirus, in an otherwise healthy outpatient. While the patient may at first appreciate a diagnosis, chances are they will not appreciate the medical bill to come.

Financial consequences 

“Complicated” is an understatement when describing the laboratory billing and reimbursement landscape today. For both private and government payers, internal policies govern what procedures will be reimbursed. Payers may limit coverage in situations deemed over-testing, or when testing is used outside of the intended patient population. What this means is that over-testing is often accompanied by big bills that the performing laboratory absorbs or passes along to patients. Laboratories that can’t cover the cost of their reagents, labor, and overhead are economically unviable, and the demise of laboratories will ultimately decrease access to critical medical tests. Likewise, when patients receive large bills for results that did not meaningfully contribute to their medical care, we’ve done them a disservice. The patients who suffer the most from these situations are those who are already vulnerable, such as people who live in areas with limited access to healthcare, and economically underserved populations.

What diagnostic stewardship really means

First, let’s clarify what diagnostic stewardship is NOT. It does not mean limiting access to tests when care is needed or “rationing” tests. Quite simply, it’s following the diagnostic value chain -  doing the right test for the right patient at the right time. A laboratory test, when used appropriately, should have the potential to improve patient outcomes and lead to clear, actionable results. Laboratory testing is only one part of the patient journey with financial implications and as such, we should endeavor to allocate laboratory resources to high-value interventions.

Evidence-based testing: raising quality and reducing burden

Guidelines from organizations such as CDC, IDSA, ASM, and AMP are powerful tools for diagnostic stewardship that are based on systematic reviews of current medical literature or expert consensus. For example, IDSA guidelines for infectious diarrhea address when targeted versus multiplex syndromic panels may be more appropriate, and when testing for C. difficile is not recommended. When testing for respiratory disease in healthy outpatients, a small panel (3-5 targets) with actionable targets (e.g., influenza that could benefit from oseltamivir) is likely preferable to a 25+ target panel, and this approach is supported by recent guidelines from ADLM. The recommendations found in guidelines clarify clinical pathways and help to focus resources where they can truly benefit patient care.

The stewardship playbook: practical strategies to reduce over-testing 

Education on guidelines and pre-test probability for physicians is a commendable goal, but often daunting given the time constraints faced by physicians today. In addition to educational efforts, laboratorians can help our physician colleagues through electronic interventions in the EHR. Creating evidence-based algorithms in order sets, and reflex criteria tied to symptoms or risk factors may be a useful strategy. There are several intervention strategies such as hard stops, soft stops, and best practice alerts to be considered. Stewardship teams in collaboration with the laboratory and physicians can create successful interventions with minimal impact to the workflow of busy physicians in their day-to-day tasks. Another option specific to multiplex panels is the idea of flexible, tiered testing that starts with the more common and actionable pathogens and reflexes only when needed. Whatever method is used, feedback mechanisms such as dashboards, peer comparisons, and audits are critical to measure the success of the intervention.

Stewardship builds value for everyone 

Stewardship done right benefits everyone involved in the care journey. Patients get clearer answers with lower bills and avoid unnecessary collections and treatments. Physicians get actionable results with less noise to cause distractions. Laboratories are more likely to be reimbursed for testing while payers get high clinical value per dollar.  Health systems can use stewardship efforts to achieve alignment with value-based care and quality goals.  Stewardship is a shared responsibility, spanning the laboratory, physician, payers, and assay manufacturers. Technology such as clinical decision support tools, analytics dashboards, and even AI-driven triage will be critical in automating testing decisions moving forward.

From “more” to “meaningful” 

We have a culture challenge facing us today where “more” feels safer. Even when there is low pre-test probability, we’re fearful of missing something. Some of that is from cognitive biases towards risk avoidance – such as action bias where we favor action over inaction. There may also be misaligned incentives or outdated habits that cause over-testing. Effective marketing from vendors or pressure from patients may also contribute to our culture of “more”. However, regardless of where you are in the healthcare ecosystem, I will leave you with a call to action. Let’s move from “more” to “meaningful.” Testing with intention contributes to a more sustainable healthcare environment to effectively serve our beautifully diverse patient populations and contributes to health equity.