Diagnostic Errors and How to Avoid Them

Educational Objectives

The goal of this program is to reduce diagnostic errors. After hearing and assimilating this program, the clinician will be better able to:

1. List common causes of diagnostic errors.
2. Distinguish between systemic and cognitive diagnostic errors.
3. Implement changes to reduce systemic and cognitive diagnostic errors.

Summary

Case: Anne Wheaton presented to emergency department (ED) with excruciating right abdominal pain, unable to stand up; findings included white blood cell count of 9000/μL, normal urinalysis, left ovarian cyst on computed tomography (CT), and no evidence of kidney stone; patient diagnosed with occult kidney stone (but unlikely given normal urinalysis); pain continued; primary care provider reviewed CT, treated patient for constipation and kidney stones, and prescribed narcotic for pain; severe pain continued; patient attended different ED, where clinician noticed changes in right ovary on original CT and ordered Doppler ultrasonography; patient diagnosed with ovarian torsion and underwent ovariectomy

Diagnostic error: possibility of diagnostic error most common concern of patients interacting with health care system; ECRI Institute identified diagnostic error as most common, catastrophic, and costly concern related to patient safety in 2018 (harms 500,000 people annually)

Definition of diagnostic error: Institute of Medicine (IOM) published Improving Diagnosis in Health Care; clinicians should become aware of potential changes they can implement to improve diagnoses within their practices; report defines diagnostic error as failure to establish accurate and timely explanation of patient’s problems or communicate explanation to patient; accurate diagnosis implies complete information (eg, knowing subtype and genotype of cancer); timely diagnosis undefined and not included in guidelines; communication issues common problem in medical systems

Studies: claims data — diagnostic error most common reason for malpractice claims (accounts for as many claims as every other reason combined) and claims for diagnostic errors most costly; in study of ≈7000 claims in obstetrics and gynecology, ≈10% concerned obstetrical patients and another ≈10% involved gynecological patients; of these, 10% to 15% of claims related to diagnostic errors, and most claims related to procedures and perinatal problems; other studies — in studies that used standardized patients trained to portray classic conditions, diagnostic error observed in 13% of cases; chart reviews suggest that 1 in 20 patients exposed to diagnostic error every year (suggests that several diagnostic errors made during lifetime of individual patient); autopsies — show major discrepancies in 10% to 20% of diagnosed patients

Outcomes: diagnostic error among top 10 causes of death, affecting 40,000 to 80,000 Americans annually; hospitals average 10 deaths annually from diagnostic error

Reasons for errors: in obstetrics and gynecology, many errors made by clinicians in other specialties who care for obstetric or gynecologic patients; fewer autopsies being performed (errors may remain unnoticed); clinicians may not inform colleagues of diagnostic errors; patients who experience harm unlikely to return to same clinician or inform them of misdiagnosis; human nature may make clinicians overconfident; in Being Wrong, Kathryn Schulz discusses feelings associated with being wrong and tendency for humans to believe themselves correct unless other feedback provided

Settings of diagnostic errors: data from Controlled Risk Insurance Company (CRICO) show that most errors associated with ambulatory care, with ED and inpatient care settings also commonly associated with diagnostic errors; claims data show that most diagnostic errors not associated with rare conditions (having rare condition places patient at risk, but errors usually associated with failure to diagnose common disorders); diagnostic process often characterized by unexplained delays

Factors contributing to errors: diagnosis difficult and complex; making diagnosis depends on patient, clinician, and health care system; International Classification of Diseases recognizes >12,000 diseases, and many new diseases added each year; most errors occur because of breakdown in diagnostic process (clinician may miss element of history or physical examination or misinterpret key data, eg, CT); fortunately, most diagnostic errors do not cause harm; diagnosis may be missed if patient does not return for follow-up or presents at early stage with nonspecific symptoms

Root cause analysis: IOM identified health care system as frequent source of errors and emphasizes need to focus on coordination, communication, policies, and procedures; in study of 100 cases of diagnostic error, speaker shows most errors attributable to both system and cognitive issues, with cognitive errors made in ≈75% of cases and system errors in ≈67% of cases; normalization of deviance — occurs when clinician becomes accustomed to status quo (eg, unavailability of certain specialists at night or on weekends) and does not bring chronic problems to attention because of belief that issues unlikely to be corrected

System errors: communication most important system-related problem; examples — ≈50% of primary care providers have no system for tracking tests ordered; critical laboratory abnormalities not followed up in 8% of cases; for inpatients, providers fail to follow up on 62% of test results that become available after discharge

Cognitive errors: clinicians may be unfamiliar with unusual disorders; faulty data gathering factors in 14% of cases of error; however, most common reason for cognitive error failure to synthesize information correctly; paradigm for diagnostic thinking — recognition center of brain uses subconscious processing to make diagnosis quickly (clinicians primarily rely on this intuitive system); without recognition, clinician must engage in deliberate, conscious thought and contemplate differential diagnosis; however, practicing clinicians often do not employ this level of thinking (study shows that in 80% of cases in which diagnosis incorrect, no differential diagnosis listed in chart); availability heuristic — intuitive system of brain engages in shortcuts and tricks (may be subconscious); fast, effortless, and usually results in correct diagnoses; drawbacks that clinician may not stop to consider differential diagnosis and may have limited experience with other disorders in differential diagnosis (availability not always linked to correct diagnosis)

Intuition vs consideration: confidence of clinician in diagnosis correlates poorly with correctness of diagnosis; in study based on national board examinations in internal medicine that assessed whether test-taker uncertain of correct response should return to think about question or rely on intuition, reconsidering questions associated with higher test scores; several studies confirm that examinee who changes answer after reconsideration twice as likely to change wrong answer to right answer than change right answer to wrong answer; intuition imperfect and responsible for many diagnostic errors

Analysis of case: system problems — unclear whether CT read by radiologist or results conveyed to other providers; no plan made for follow-up; cognitive errors — diagnosis of ovarian torsion should have been considered, but clinicians may have been thinking in wrong context (not considering gynecological conditions) or failed to consider other diagnoses (premature closure); clinician may wrongly focus on first disease consistent with findings (phenomenon described by economist Herbert Simons as “satisficing”, which is opposite of optimizing); diagnostic and cognitive errors recognized in many fields of endeavor

Preventing cognitive errors: clinicians — practice reflectively, consider opposites, and develop comprehensive differential diagnoses; use mnemonics, checklists, and diagnostic-specific decision support resources to think more comprehensively (using Google to generate differential diagnosis associated with poor sensitivity and specificity); obtaining second opinion good idea (second opinion associated with change in diagnosis in 2% to 5% of cases in radiology or pathology and in 10% to 20% of cases in internal medicine); emphasize team approach and involve patients and nurses in diagnostic process; convey to patient whether diagnosis uncertain and develop plan for when and how to follow up; patients — be good historian; participate in cancer screening; keep own records of tests; ask about other causes of problem; provide clinicians with feedback about diagnostic performance; leaders — identify and discuss diagnostic errors; tackle system problems; invest in clinical decision support tools; encourage feedback; facilitate second opinions; improve follow-up

Society to Improve Diagnosis in Medicine: coalition of 51 organizations focused on improving diagnosis

Readings

Graber ML: The incidence of diagnostic error in medicine. BMJ Qual Saf 2013 Oct;22 Suppl 2:ii21-ii27; National Academies of Sciences, Engineering, and Medicine: 2015. Improving Diagnosis in Health Care. Washington, DC: The National Academies Press. Available at: https://www.nap.edu/catalog/21794/improving-diagnosis-in-health-care. Accessed March 13, 2019; Schulz K: Being Wrong: Adventures in the Margin of Error. New York, NY: HarperCollins Publishers; 2010; Singh H et al: Measures to improve diagnostic safety in clinical practice. J Patient Saf 2016 Oct 20 [Epub ahead of print]; Singh H et al: System-related interventions to reduce diagnostic errors: a narrative review. BMJ Qual Saf 2012 Feb;21(2):160-70; Singh H, Graber ML: Improving diagnosis in health care — the next imperative for patient safety. N Engl J Med 2015 Dec 24;373(26):2493-5; Society to Improve Diagnosis in Medicine: Clinician checklists. Available at: https://www.improvediagnosis.org/clinician-checklists/. Accessed March 14, 2019; Thomas NJ et al: An international assessment of a web-based diagnostic tool in critically ill children. Technol Health Care 2008;16(2):103-10.

Disclosures

For this program, members of the faculty and planning committees reported nothing to disclose.

Acknowledgements

Dr. Graber was recorded at the 32nd Annual Sanford H. Cole, MD, Memorial Ob/Gyn Symposium, presented by Baptist Health South Florida, and held January 25, 2019, in Miami, FL. For more information about upcoming CME meetings presented by Baptist Health South Florida, please visit cme.baptisthealth.net. MThe Audio Digest Foundation thanks the speakers and the sponsors for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

OB661001

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.