Diagnostic errors — failures to correctly identify a patient’s condition in a timely manner — are among the most prevalent and damaging forms of medical negligence. Studies consistently identify missed, delayed, and incorrect diagnoses as a leading cause of preventable patient harm. When a diagnostic error leads to injury, the consequences can be severe and lasting.
Missed Diagnosis
A missed diagnosis occurs when a provider fails to identify a condition that was present and should have been detected. This is particularly dangerous with time-sensitive conditions such as cancer, heart attack, stroke, pulmonary embolism, and meningitis. The failure may result from inadequate testing, dismissal of symptoms, or failure to follow up on abnormal findings.
Delayed Diagnosis
A delayed diagnosis is one that was eventually reached, but not in time to prevent significant harm. Even when a correct diagnosis is ultimately made, the delay between symptom onset and identification can allow a condition to progress to a more serious or irreversible stage. The question is whether a reasonably competent provider would have reached the diagnosis sooner.
Misdiagnosis
A misdiagnosis occurs when a provider incorrectly identifies a patient’s condition, leading to treatment that is ineffective or actively harmful. A patient treated for acid reflux when they are actually experiencing a cardiac event is a classic and dangerous example. The time spent treating the wrong condition delays appropriate care.
Failure to Recognize Complications
Even when an initial diagnosis is correct, providers can fail to recognize complications that arise during or after treatment. Post-surgical infections, medication reactions, and worsening conditions that go undetected can cause significant harm if not identified and addressed promptly.
Failure to Order Appropriate Testing
Sometimes the error occurs not in interpreting test results, but in failing to order appropriate diagnostic tests in the first place. A provider who dismisses a patient’s symptoms without ordering indicated imaging, lab work, or specialist referrals may be liable if a serious condition goes undetected as a result.