Getting clearer on overdiagnosis

Area of Science:

• Medical Diagnosis
• Healthcare Quality
• Diagnostic Accuracy

Background:

• Overdiagnosis is a significant issue across various medical fields, including cancer screening, chronic kidney disease, diabetes, depression, and attention deficit hyperactivity disorder.
• It leads to unnecessary medical interventions and patient anxiety when a diagnosed condition is not a harmful disease.

Purpose of the Study:

• To define and describe the phenomenon of overdiagnosis.
• To investigate the underlying reasons for overdiagnosis.
• To propose and differentiate two distinct types of overdiagnosis: misclassification and maldetection.

Main Methods:

• Conceptual analysis of the overdiagnosis phenomenon.
• Illustration of misclassification overdiagnosis using chronic kidney disease (CKD) diagnosis based on biomarkers or patient-reported symptoms.
• Illustration of maldetection overdiagnosis using thyroid cancer diagnosis, where harmful and non-harmful cases are indistinguishable even with gold-standard tests.

Main Results:

• Overdiagnosis is categorized into two types: misclassification and maldetection.
• Misclassification overdiagnosis occurs when diagnostic thresholds identify individuals without harmful disease.
• Maldetection overdiagnosis arises when harmful and non-harmful cases cannot be distinguished at the time of diagnosis.

Conclusions:

• The conceptual distinction between misclassification and maldetection overdiagnosis provides clarity on the phenomenon.
• Understanding these types is a foundational step toward developing effective strategies to mitigate overdiagnosis in healthcare.
• Addressing overdiagnosis is essential for improving patient outcomes and healthcare resource allocation.