Prevalence estimates of asthma or COPD from a health interview survey and from general practitioner registration: what's the difference?

• Published in: European journal of public health 2006-02, Vol.16 (1), p.101-105
• Main Authors: Mohangoo, Ashna D., van der Linden, Michiel W., Schellevis, François G., Raat, Hein
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Asthma; Asthma - epidemiology; Bronchitis; Chronic illnesses; Chronic obstructive pulmonary disease; Family Practice; Female; Gender; general practice registration; Health insurance; health interview survey; Health services; Health Surveys; Humans; Interviews; Interviews as Topic; Lung diseases; Male; Medical records; Middle Aged; Netherlands - epidemiology; Patients; Population; prevalence; Primary care; Public health; Pulmonary Disease, Chronic Obstructive - epidemiology; Questionnaires; Registration; Registries; Self report; Smoking
• ISSN: 1101-1262; 1464-360X
• DOI: 10.1093/eurpub/cki043

Background: The aim of this study was to compare prevalence estimates of asthma or chronic obstructive pulmonary disease (COPD) derived from self-report in a health interview survey and from general practitioners' (GPs') medical records, and to explain any differences. Methods: the presence of asthma or COPD was measured by self-report in a random sample of 104 general practices in the Netherlands (n = 19 685) participating in the second Dutch National Survey of General Practice (DNSGP-2). This was compared with the presence of GP-diagnosed asthma or COPD in the same population as recorded using the International Classification of Primary Care by their GPs during a 12-month period. Gender, age, health insurance, ethnic background, educational level, tobacco exposure, and other symptoms and conditions were evaluated as explanatory variables using logistic models. Results: The prevalence of self-reported asthma or COPD (9.7%) was almost twice as high as the prevalence based on GP information (5.2%). The medical records of patients who reported having asthma or COPD, without having a diagnosis in their medical records, usually included other respiratory conditions. Patients reporting no asthma or COPD but whose medical records carried a diagnosis of asthma or COPD, were relatively older (P < 0.01) and tended to be exposed to smoking in their home (P < 0.05). Conclusions: Two methods for estimating prevalence of asthma or COPD yielded different results: compared with GP medical records, self-reported prevalence shows an overestimation in people who suffer from other respiratory conditions and an underestimation in elderly persons living in a smoky environment.