In the world of healthcare, the spotlight often shines on frontline clinicians, dramatic surgical interventions, or groundbreaking therapies. Yet, behind the scenes, a quiet revolution is reshaping the foundation of clinical decision-making: diagnostic stewardship. At the core of this movement lies the effort to ensure that the right tests are ordered for the right patients at the right time and that the results are interpreted and acted upon appropriately. Though often overlooked, Genesis Reference Laboratories explains that this discipline is emerging as one of the most impactful ways to enhance patient safety, improve outcomes, and reduce unnecessary costs.
Diagnostic stewardship centers on laboratory diagnostics—the complex system of tests that inform the majority of medical decisions. From blood cultures to imaging panels, testing is the bedrock upon which diagnoses are built. But when testing is misused—whether through overuse, underuse, or misinterpretation—the consequences can be serious, even fatal. Delayed diagnoses, inappropriate treatments, prolonged hospital stays, and systemic inefficiencies all too often stem from flawed diagnostic practices.
Misused Tests: When More Isn’t Better
One of the most pervasive issues in diagnostic stewardship is the misuse of laboratory tests. This includes both over-testing and inappropriate test selection. In many healthcare settings, clinicians order tests reflexively, either out of habit, lack of clarity, or perceived expectations. For example, ordering daily labs for stable inpatients without clinical justification is a common practice that often yields little value, consumes resources, and can lead to iatrogenic anemia or incidental findings that complicate care.
Blood cultures are another notorious example. While critical in detecting bloodstream infections, blood cultures are frequently ordered when the pretest probability of infection is low, leading to false positives due to contamination. These false positives can result in unnecessary antibiotic use, prolonged hospitalizations, and increased costs. A 2020 study published in Clinical Infectious Diseases found that up to 50% of positive blood cultures were actually contaminants rather than true infections. This not only causes clinical confusion but also contributes to antibiotic resistance—a growing global health threat.
Similarly, urine cultures are routinely over-ordered in asymptomatic patients, particularly the elderly or those with catheters. Positive cultures in these cases often reflect colonization rather than infection, leading to overtreatment. Diagnostic stewardship efforts have shown that implementing strict criteria for urine culture ordering significantly reduces unnecessary antibiotic use without compromising patient outcomes.
The Impact of Delays: A Dangerous Waiting Game
While over-testing is problematic, under-testing or delayed testing can be equally, if not more, dangerous. Delays in diagnosis often arise when appropriate tests are not ordered promptly, or when results are not acted upon in a timely manner. Cancer is a prime example of this perilous lag. A patient presenting with vague symptoms like fatigue or weight loss may undergo a series of tests over weeks or months before a definitive diagnosis is reached. In the interim, the disease may progress to a less treatable stage.
Similarly, delays in identifying infectious diseases can have catastrophic consequences. During the COVID-19 pandemic, delays in testing and reporting contributed to widespread transmission and missed opportunities for timely intervention. In routine practice, delayed diagnosis of sepsis—a life-threatening response to infection—can occur when blood cultures or other relevant tests are not expedited. Every hour of delay in appropriate antibiotic therapy increases mortality by as much as 7.6%, according to a landmark study in Critical Care Medicine.
Furthermore, the turnaround time of tests can be a hidden driver of delays. Even when appropriate tests are ordered, bottlenecks in lab processing, data entry errors, or lack of real-time alerts can prevent timely clinical action. This highlights the need for not just better test ordering, but also smarter integration of diagnostics into the clinical workflow.
Reform and Opportunity: Building a Culture of Diagnostic Safety
Fortunately, the tide is turning. A growing number of health systems are embracing diagnostic stewardship as a formal discipline, complete with dedicated teams, performance metrics, and quality improvement initiatives. The key lies in fostering collaboration between clinicians, laboratorians, pharmacists, IT professionals, and patient safety officers. Together, they can identify patterns of misuse, streamline ordering practices, and develop decision support tools that guide clinicians toward evidence-based testing.
One promising strategy is the use of clinical decision support (CDS) tools embedded within electronic health records (EHRs). These tools can prompt providers when ordering tests that are frequently misused, such as C. difficile testing without diarrhea or imaging for uncomplicated headaches. By incorporating real-time guidance and flagging inappropriate orders, CDS tools serve as guardrails against misuse.
Audit and feedback programs are also gaining traction. In these initiatives, clinicians receive regular reports on their test ordering patterns, compared to evidence-based benchmarks or peer performance. Studies have shown that this simple act of feedback can lead to meaningful reductions in unnecessary testing.
Educational campaigns play a pivotal role as well. Many diagnostic errors stem from knowledge gaps or cognitive biases. Training clinicians on the principles of diagnostic stewardship—including when not to test—can recalibrate diagnostic habits and promote more thoughtful, patient-centered care.
In addition, laboratories themselves are evolving from passive service departments to active participants in clinical care. Lab directors and microbiologists are increasingly involved in rounds, consultations, and stewardship initiatives. This culture shift underscores the lab’s role not just in producing data, but in guiding diagnosis.
A Patient-Centered Approach
At its heart, diagnostic stewardship is about putting patients first. Every unnecessary test is a missed opportunity to focus on what matters. Every delayed diagnosis is a potential harm. By rethinking the role of diagnostics, healthcare systems can reduce costs, enhance outcomes, and most importantly, safeguard the trust patients place in their caregivers.
The quiet revolution of diagnostic stewardship may not make headlines, but its impact resonates deeply throughout the healthcare system. As awareness grows, and as labs and clinicians work together to build smarter, safer testing practices, the future of patient safety looks brighter—and more precise—than ever before.