Use of the terms “overdiagnosis” and “misdiagnosis” in the included studies
| First author, year [ref.] | Population details | Terms used | Reason for classification as overdiagnosis | Estimated prevalence of overdiagnosis/misdiagnosis | |
| van Dijk, 2015 [30] | Population study (n=4882) with sample aged ≥40 years (mean±sd age 57±11 years), including former and current smokers; symptomatic; 4% had known chronic bronchitis | Overdiagnosis, misdiagnosis | Discordant results between 1) post-bronchodilator FEV1/FVC <0.7 but ≥LLN; and 2) FEV1/FVC <0.7 + FEV1 <80% predicted | Prevalence of spirometric airflow limitation was 17% by fixed ratio and 11% by LLN Patients who had airflow limitation meeting fixed ratio but not LLN were more likely to have cardiovascular disease (odds ratio 1.52) | |
| Llordés, 2015 [10] | Smokers aged ≥45 years (n=1738), some with symptoms (21–46% depending on symptom); 10.5% pre-existing COPD diagnosis | Overdiagnosis | Normalisation of spirometry after 4 weeks of treatment COPD diagnosis despite no evidence of airflow obstruction on spirometry (defined as post-bronchodilator FEV1/FVC <0.7) Discordant results for COPD diagnosis based on post-bronchodilator FEV1/FVC <0.7 but ≥LLN | In subjects with a new diagnosis of COPD by fixed ratio, 16% presented normal spirometry after 4 weeks of treatment 15.6% of people with physician-diagnosed COPD did not fulfil the spirometric criteria for COPD Prevalence of COPD using LLN was 15.5% compared to 24.3% using fixed ratio | |
| Spero, 2017 [15] | Patients admitted to a community teaching hospital (n=6018); aged ≥18 years (mean±sd age 69.5±12.8 years); admitted for respiratory complaints with COPD as a principal or leading diagnosis and had spirometry performed during hospitalisation | Misdiagnosis, overdiagnosis | COPD diagnosis despite no evidence of airflow obstruction on spirometry, defined as post-bronchodilator FEV1/FVC <0.7 (no spirometry had been performed before the study) Discordant results for COPD diagnosis based on post-bronchodilator FEV1/FVC <0.7 but ≥LLN | 30.8% of cases of patients with a primary diagnosis of COPD had normal pulmonary function tests (COPD diagnosis refuted) Significant correlation between presence of hypertension, obstructive sleep apnoea, coronary artery disease, congestive heart failure and misdiagnosis of COPD 10.7% of spirometry studies diagnosed as airflow obstruction by GOLD criteria would have been considered normal by LLN criteria (these patients were more likely never-smokers and asymptomatic) | |
| Lamprecht, 2011 [25] | General population sample (n=1258), some with symptoms consistent with COPD; aged >40 years; 5.6% had a previous physician diagnosis of COPD, emphysema or chronic bronchitis | Overdiagnosis | Discordant results for COPD diagnosis based on post-bronchodilator FEV1/FVC <0.7 but ≥LLN | 6.4% of the study population had discordant obstructive cases (FEV1/FVC <0.7 and ≥LLN) Discordant cases had similar profiles to those with restrictive disease and these subjects more often had diagnosis of heart disease than those with normal function | |
| Schermer, 2008 [26] | Symptomatic adults (n=14 056) referred for spirometry by their GP for suspected COPD; mean±sd age 53.0±21.4 years; 69% current/former smokers | Overdiagnosis | Discordant results for COPD diagnosis based on post-bronchodilator FEV1/FVC <0.7 but ≥LLN Only pre-bronchodilator spirometry result | Age years | Fixed ratio overdiagnosis |
| 31–40 | 8.9% | ||||
| 41–50 | 15.5% | ||||
| 51–60 | 23.9% | ||||
| 61–70 | 33.2% | ||||
| 71–80 | 38.7% | ||||
| ≥81 | 42.7% | ||||
| 25.3% of obstructive pattern diagnosed by pre-bronchodilator spirometry was not classified as COPD on post-bronchodilator spirometry | |||||
| García-Rio, 2011 [27] | General population sample (n=3802) aged 40–80 years, including smokers, some with symptoms consistent with COPD | Overdiagnosis | Discordant results for COPD diagnosis based on post-bronchodilator FEV1/FVC <0.7 but ≥LLN | 4.6% of subjects aged 40–80 years had overdiagnosed COPD | |
| Wang, 2013 [28] | Population study (n=1382); sample aged 56–84 years (mean±sd age 67.7±13.3 years); never-smokers; asymptomatic; no previous diagnosis of asthma, COPD or heart disease | Overdiagnosis | Discordant results for COPD diagnosis based on post-bronchodilator FEV1/FVC <0.7 but ≥LLN | 9.5% of asymptomatic population were diagnosed with COPD using the fixed criterion compared with 4.3% using the LLN (using spirometric reference values that were specifically derived for the study population in Jinan, China) | |
| Fisher, 2016 [14] | Members of the 1921 birth cohort from North-East England recruited around their 85th birthday (n=845); >50% former smokers; symptomatic; 16.6% had previous diagnosis of COPD; median number of comorbid diseases was 5 | Overdiagnosis, misdiagnosis | COPD diagnosis despite no evidence of airflow obstruction on spirometry, defined as either 1) post-bronchodilator FEV1/FVC <0.7, 2) FEV1/FVC <LLN, or 3) Global Lung Function Initiative criteria Discordant results for COPD diagnosis based on post-bronchodilator FEV1/FVC <0.7 but ≥LLN | 75.6% of those with physician-diagnosed COPD met the GOLD criteria for spirometry; however, using the LLN only 41.1% had airflow obstruction 44.5% of the healthy reference group who were asymptomatic met the GOLD cut-off for COPD 24.4% of those with physician-diagnosed COPD did not satisfy spirometric criteria for COPD using GOLD criteria | |
| Steinacher, 2012 [29] | Consecutive patients of an outpatient heart failure clinic (n=89); median age 67.0 years; 55% former/current smokers; 12.4% with self-reported COPD; majority New York Heart Association class II heart failure | Overdiagnosis, misdiagnosis | COPD diagnosis despite no evidence of airflow obstruction on spirometry, defined as post-bronchodilator FEV1/FVC <0.7 Discordant results for COPD diagnosis based on post-bronchodilator FEV1/FVC <0.7 but ≥LLN Heart failure affects spirometry interpretation; clinical symptoms overlapping with those of COPD | Among participants who did not demonstrate airflow obstruction on spirometry, 6% had a previous diagnosis of COPD; these 6% were identified as false positives by the GOLD criteria Application of the GOLD criteria led to a significantly higher rate of COPD in the heart failure population (43.8%) compared to using the LLN (24.7%) 12.3% patients who presented an FEV1/FVC >0.7 had an FVC <LLN and had measured FVC experimentally substituted by 80% of predicted FVC, to detect airway obstruction that was possibly masked by heart failure-related restriction; this led to a decline in FEV1/FVC to <0.7 in eight cases and <LLN in seven cases | |
| Minasian, 2013 [17] | Patients with stable chronic heart failure (n=187); sample aged ≥18 years (mean±sd 69±10 years); 83% former or current smokers; 82% reported dyspnoea | Overdiagnosis | Discordant results for COPD diagnosis based on post-bronchodilator FEV1/FVC <0.7 but ≥LLN COPD diagnosis despite no evidence of airflow obstruction on spirometry, defined as post-bronchodilator FEV1/FVC <0.7 or <LLN Clinical symptoms and risk factor profile of heart failure overlapping with those of true COPD | COPD prevalence varied according to the definition, with 19.8% according to the LLN definition compared to 32.1% using GOLD definition after 3 months of follow-up 32% of patients with history of obstructive lung disease did not have GOLD COPD, and 50% did not meet LLN COPD according to spirometry 74% of patients with misclassified COPD (discordant spirometry) had respiratory symptoms and a smoking history and 64% of non-COPD (with heart failure) also had respiratory symptoms and smoking history | |
| Zwar, 2011 [19] | Patients (n=445) aged 40–80 years (mean age 65 years), who from GP practice records were considered to have a diagnosis of COPD, emphysema or chronic bronchitis; 30.5% current smokers | Misdiagnosis | COPD diagnosis despite normal spirometry (pre- and post-bronchodilator FEV1/FVC >0.7, FVC and FEV1 >80% of predicted values) or restriction (pre- and post- FEV1/FVC >0.7, FVC and FEV1 <80% of predicted values) or asthma | Of all patients with known COPD, 42.2% had post-bronchodilator showing asthma only, normal spirometry or other spirometric diagnoses such as restriction | |
| Starren, 2012 [21] | Patients referred for spirometry by GPs with definite COPD (n=1156); mean±sd age 61.3±15.6 years; 65% smokers | Misdiagnosis | COPD diagnosis despite normal spirometry (pre- and post-bronchodilator FEV1/FVC >0.7, FVC and FEV1 >80% of predicted values) or restriction (pre- and post- FEV1/FVC >0.7, FVC and FEV1 <80% of predicted values) or asthma | 19.4% of patients with definite COPD according to physicians did not demonstrate COPD on spirometry (2% had asthma, 4% had restriction and 13% had no airway obstruction) | |
| Spyratos, 2016 [11] | Population study (n=3200) including current and former smokers aged >40 years (mean±sd age 60.5±13.4 years); 8.6% had previously physician-diagnosed COPD | Overdiagnosis | COPD diagnosis despite normal spirometry (pre- and post-bronchodilator FEV1/FVC >0.7, FVC and FEV1 >80% of predicted values) or restriction (pre- and post- FEV1/FVC >0.7, FVC and FEV1 <80% of predicted values) | 9.6% of group diagnosed with COPD had been overdiagnosed | |
| Hill, 2010 [12] | Patients aged ≥40 years with a smoking history of ≥20 pack-years recruited from primary care practices (n=382); 11% had self-reported pre-existing COPD | Overdiagnosis | COPD diagnosis despite no evidence of airflow obstruction on spirometry, defined as post-bronchodilator FEV1/FVC <0.7 and FEV1 <80% predicted | 29.6% with diagnosis of COPD had been overdiagnosed (11.8% of total study population who had medical records reviewed) | |
| Gershon, 2018 [13] | Random population-based sample of adults aged >40 years (n=1403), including symptomatic subjects with smoking history; 8.8% with physician diagnosis of COPD | Overdiagnosis | COPD diagnosis despite no evidence of airflow obstruction on spirometry, defined as post-bronchodilator FEV1/FVC <0.7 | Of all participants included in analysis, 5.1% had overdiagnosed COPD | |
| Stafyla, 2018 [16] | Subjects (n=186) aged >40 years (mean±sd age 62.3±12.6 years) recruited from primary healthcare settings; all current or former smokers; 82.3% had respiratory symptoms, 10.2% with known COPD | Overdiagnosis, misdiagnosis | COPD diagnosis despite no evidence of airflow obstruction on spirometry, defined as post-bronchodilator FEV1/FVC <0.7 (no spirometry had been performed before the study) | 61.4% of non-COPD subjects according to spirometry had been misdiagnosed with COPD | |
| Roberts, 2009 [18] | Patients referred for spirometry with clinical diagnosis of COPD to assess severity or suspected diagnosis for diagnostic confirmation (n=503); mean±sd age 63.8±11.3 years, including symptomatic smokers; 64.8% had received prior diagnosis of COPD | Misdiagnosis | COPD diagnosis despite normal spirometry (pre- and post-bronchodilator FEV1/FVC >0.7, FVC and FEV1 >80% of predicted values) or restriction (pre- and post- FEV1/FVC >0.7, FVC and FEV1 <80% of predicted values) | 37.7% of patients that had a clinical diagnosis of COPD had spirometry results incompatible with a diagnosis of COPD | |
| Lacasse, 2012 [20] | Patients discharged from acute care hospitals with a principal diagnosis of COPD (n=1221); mean±sd age 73.1±12.2 years; 81.9% smokers | Misdiagnosis | COPD diagnosis despite normal spirometry (post-bronchodilator FEV1/FVC >0.7) | 15.2% of patients discharged with COPD as their principal diagnosis were confirmed to not have COPD according to a review of their medical records and spirometry by two pulmonologists | |
| Walters, 2011 [22] | Patients in general practice with either a recorded diagnosis of COPD and/or record of current treatment with the specific COPD therapy tiotropium (n=341); mean±sd age 62.3±8.6 years; 39% current smokers; symptomatic | Misdiagnosis | COPD diagnosis despite normal spirometry (pre- and post-bronchodilator FEV1/FVC >0.7, FVC and FEV1 >80% of predicted values, FVC >80% of predicted values) or restriction (pre- and post- FEV1/FVC >0.7, FVC and FEV1 <80% of predicted values) | 31% of patients did not meet the criteria for COPD; of these, three patterns were found on spirometry: 56% had normal lung function, 7% had mild airflow limitation (FEV1 <80% of predicted), and 37% had restrictive lung function | |
| Queiroz, 2012 [23] | Patients recruited from selected primary healthcare centres with no acute respiratory symptoms (n=200); sample aged ≥40 years (mean±sd age 65.0±10.4 years); minimum of 20 pack-years’ smoking history or biomass fuel exposure; majority were symptomatic | Misdiagnosis, overdiagnosis | COPD diagnosis despite normal spirometry (post-bronchodilator FEV1/FVC >0.7) | 14.6% of individuals who did not meet the diagnostic criteria for COPD reported a previous diagnosis of COPD | |
| Heffler, 2018 [24] | Consecutive patients referred by GPs for spirometry (n=300); mean±sd age 58.5±18.9 years, including current or former smokers; majority had symptoms; 25% physician diagnosis of COPD | Misdiagnosis, overdiagnosis | COPD diagnosis despite normal spirometry (post-bronchodilator FEV1/FVC >0.7) | 86.7% of those with previous doctor-diagnosis of COPD had non-concordant spirometric patterns | |
| Bellia, 2003 [31] | Asthmatic subjects from pulmonary or geriatric institutions (n=128); mean±sd age 73.1±6.3 years; most symptomatic | Misdiagnosis | Clinical features of asthma overlapping with those of COPD | 19.5% of newly diagnosed asthmatics had received a prior wrong diagnosis of COPD and/or emphysema | |