Use of the terms “overdiagnosis” and “misdiagnosis” in the COPD literature: a rapid review

Challenges in the diagnostic process of chronic obstructive pulmonary disease (COPD) can result in diagnostic misclassifications, including overdiagnosis. The term “overdiagnosis” in general has been associated with variable definitions. In connection with efforts to reduce low-value care, “overdiagnosis” has been defined as a true positive diagnosis of a condition that is not associated with any harm in the diagnosed person. It is, however, unclear how the term “overdiagnosis” is used in the COPD literature. We conducted a rapid review of the literature to explore how the terms “overdiagnosis” and “misdiagnosis” are used in the context of COPD. Electronic searches of Medline were conducted from inception to October 2018, to identify primary studies that reported on over- and/or misdiagnosis of COPD using these terms. 28 articles were included in this review. Overdiagnosis and misdiagnosis in COPD were found to be used to describe five main concepts: 1) physician COPD diagnosis despite normal spirometry (14 studies); 2) discordant results for COPD diagnosis based on different spirometry-based definitions for airflow obstruction (10 studies); 3) COPD diagnosis based on pre-bronchodilator spirometry results (three studies); 4) comorbidities (e.g. heart failure or asthma) that affect spirometry and have clinical features which overlap with COPD (two studies); and 5) normalisation of abnormal (post-bronchodilator) spirometry at follow-up (one study). The terms “overdiagnosis” and “misdiagnosis” were often used interchangeably and almost always referred to a false positive diagnosis. Performing (technically correct) spirometry with correct interpretation of the results could probably reduce misdiagnosis in a large proportion of the misdiagnosed cases of COPD. In addition, guidelines need to provide a more acceptable consensus spirometric definition of airflow obstruction. KEY POINTS: In the COPD literature, the terms “overdiagnosis” and “misdiagnosis” are often used interchangeably and almost always refer to a false positive diagnosis. Use of spirometry with correct interpretation of the results can avoid a substantial proportion of cases of misdiagnosis of COPD. EDUCATIONAL AIMS: To explore the use of the terms “overdiagnosis” and “misdiagnosis” in the COPD literature. To identify the main sources of overdiagnosis and misdiagnosis in COPD.