Comparison of existing symptom-based questionnaires for identifying COPD in the general practice setting.
OBJECTIVE
Underdiagnosis of COPD is widespread, at least in part due to underuse of spirometry. Symptom-based questionnaires may be helpful as an adjunct to spirometry. The aim of this study was to determine which types of questions might aid in identifying COPD.


METHODS
Questionnaires were identified by literature review and input from a multinational advisory board of primary care providers. Questions were placed into groups and evaluated with respect to their ability to perform in two scenarios: (i) to identify persons with COPD from a general population (Case-finding scenario); and (ii) to distinguish persons with COPD from those with asthma (Differential Diagnosis scenario). Questions were retrospectively validated using the Third National Health and Nutrition Examination Survey data. Potential predictive ability was examined in bivariate and multivariate frameworks.


RESULTS
Four published question sets and six additional documents were included. There was agreement in the use of smoking and symptom-based questions, but important differences in the use of demographic, personal history and other information. Most question types had significant bivariate relationships with airway obstruction. In multivariate analysis, age, BMI, smoking status and pack-years, symptoms (cough, phlegm, dyspnoea, wheeze), and prior diagnosis consistent with asthma or COPD all showed significant ability to discriminate between persons with and without obstruction in a general population.


CONCLUSIONS
Simple self-administered questionnaires can be used to identify persons for whom spirometric testing may be especially appropriate. Development of such questionnaires will require additional study, including prospective validation of items in an appropriate clinical setting and policy recommendations on the use of these tools.
van Schayck
Constant P
CP
Department of General Practice, Research Institute Caphri, University of Maastricht, Maastricht, Netherlands.
Halbert
Ronald J
RJ
Nordyke
Robert J
RJ
Isonaka
Sharon
S
Maroni
Jaman
J
Nonikov
Dmitry
D
D003937:Diagnosis, Differential; D005194:Family Practice / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D011237:Predictive Value of Tests; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000503:physiopathology; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013147:Spirometry; D011795:Surveys and Questionnaires