OBJECTIVE: To evaluate the role of spirometry and respiratory symptoms in the detection of chronic obstructive pulmonary disease (COPD) in primary health care. DESIGN: A cross-sectional study. SETTING: A primary health centre in Landskrona, southern Sweden. SUBJECTS: 164 subjects who in 1992 had answered a postal questionnaire concerning obstructive pulmonary diseases and respiratory symptoms. They were aged 45-64 years, with a mean of 55 years. MAIN OUTCOME MEASURES: In 1997, the subjects were invited to perform a spirometry and a medical examination and to answer the same questionnaire as in 1992. Subjects with a forced expiratory volume in 1 second (FEV1)