Choose wisely: Clinical diagnostic reasoning over technological expediency
If a patient presented to the hospital with a serum calcium level of 19 mg/dL, what would you do next? From presentation to management you may have little time to evaluate if the patient resembles “stones, bones, groans, and psychiatric overtones.” Rather than refining clinical data acquisition and following a step-wise workup, proceeding immediately to imaging could appear most efficient. Although problem-solving and clinical reasoning are critical skills in the practice of medicine, technology appears to offer reprieve to the busy clinician by promising an expeditious answer, particularly for patients with complex presentations. A middle-aged woman presented to the hospital at the direction of her physician due to a laboratory finding of hypercalcemia; she had no complaints except mild fatigue. When her metabolic panel, otherwise unremarkable, showed a calcium level of 19.3 mg/dL, no time was made to further the history or exam to generate an accurate problem representation. Instead, a series of computed tomography scans (CT) was ordered, including imaging of the head, thorax, abdomen and pelvis. The extensive imaging incidentally identified an abnormality in the neck suggestive of a parathyroid tumor; only then was a parathyroid hormone (PTH) level obtained. The PTH level, key to the diagnostic workup of hypercalcemia,1. returned markedly elevated at 1,332 pg/mL (reference: 12-88 pg/mL), pointing to hyperparathyroidism, possibly a parathyroid carcinoma, as the underlying cause of her hypercalcemia. Humoral hypercalcemia of malignancy immediately became unlikely. The patient received medical treatment and subsequently underwent surgery with finding of a large complex cystic parathyroid mass that proved benign. While the non-specific and extensive CT imaging identified the potential cause, it was unnecessary. The decision to order the CT series was not the result of a strong reasoning process or a response to a hierarchy of need. By the time the patient’s PTH level was checked, she had been scanned from head to toe. A 2019 estimate of waste in the United States (US) health care system attributed up to 27.9 billion dollars to the domain of low-value screening, testing or procedures.2 The inappropriate use and overuse of diagnostic tests has been widely recognized as counter to high-value care. The American Board of Internal Medicine Foundation’s Choosing Wisely (CW) campaign. and Medicare’s Imaging Appropriate Use Criteria (AUC) program4 are two quality improvement initiatives that overlap on the goal of avoiding unnecessary imaging studies. CW focuses on changing physician and patient behavior and attitude by providing guidance on diagnostic test or procedure appropriateness. Five top tests or treatments deemed as inappropriate by numerous participating national professional health societies are listed online and accessible through a search tool of clinician lists. CW recommendations have been incorporated into institutional electronic medical record (EMR) ordering processes and into physician and patient education initiatives with some favorable results. Although the overall impact of CW on outcomes may be modest 8 or difficult to measure5 its impact on patient care remains relevant and continues to expand. The AUC, a Centers for Medicare and Medicaid Services (CMS) program, currently available in testing mode, may proceed to full implementation as soon as January of 2023. While it involves professional medical societies, health systems and clinical practices, AUC has a more narrow scope than CW. AUC focuses on decreasing inappropriate advanced diagnostic imaging services (CT, magnetic resonance and nuclear medicine imaging) for Medicare recipients who present to the clinic or emergency room. The initiative will prioritize eight common clinical problems or complaints, ranging from coronary disease and pulmonary embolism to low back pain. Critically, a major distinction between the CW and AUC is that the latter adds financial consequence to diagnostic imaging decision-making in its effort to reduce unnecessary studies. CMS will only reimburse for advanced diagnostic imaging if the ordering physician uses an approved clinical decision-making support mechanism (CDSM) in the process. The CDSM, which may be embedded within EMR systems or available within a freestanding platform, determines study appropriateness based on current guidelines and/or local best care practices. In response to concerns regarding provider burden, CMS will allow the ordering physician to delegate the CDSM consultation process to trained staff. A non-applicable option is offered if the CDSM platform does not have available evidence to inform on the appropriateness of the diagnostic test. In our patient’s case, neither CW nor AUC would have alerted the provider against proceeding with CT imaging for the work-up of hypercalcemia. The list of conditions for which imaging studies may be ordered (appropriately or inappropriately) is unconstrained and the reach of quality interventions such as CW and AUC will remain limited if not coupled with an approach that supports physician clinical reasoning during the patient encounter. Inappropriate diagnostic decisions are not usually due to lack of knowledge, but more the result of reflexive and autonomous reasoning processes that replace deliberate clinical analysis.9 Appropriate diagnostic decision-making is complex and comprises multiple steps: obtaining pertinent clinical information, developing a problem representation statement, generating a hypothesis, and selecting an illness script.The workplace can support this process by reducing unnecessary distractions, avoiding provider fatigue and prioritizing the time the physician spends in direct patient care during the encounter. Competency in diagnostic clinical reasoning is paramount to the delivery of high quality care and should be demonstrated during medical school and residency training and evaluated in the process of board certification and re-certification. The complexity of this clinical skill calls for multi-method assessments and should include the evaluation of professional competence in the actual clinical setting. Equally important, health care organizations need to offer an environment that promotes analytic reasoning at the point of care and a culture that discourages waste. When a nuanced patient walks into the emergency room, CT scans may be extremely helpful. Nonetheless, clinicians should first use clinical reasoning skills to guide them to the most likely diagnosis rather than rely on technology to do the work, even if available at their fingertips.