Sick leave in workers with asthma and COPD: the role of attitudes, perceived social norms and self efficacy.

We investigated associations of sick leave in 165 workers with asthma and COPD with three components of the Model of Planned Behavior (MPB): attitudes, social norms towards sick leave, and perceived control over sick leave and over health complaints. All participants underwent lung-function tests and completed questionnaires on sick leave, and on the MPB-components. Differences were calculated between high and low sick leave (frequency and duration) for the total group of asthma and COPD and separately for asthma and COPD. The most relevant variable within each MPB-component was selected for multivariate analysis. In the total group and in the group with asthma, low sick leave was associated with more perceived control over fatigue. In COPD, the attitude 'finding the negative consequences of sick leave more unpleasant' was associated with high sick leave. It was concluded that similarities exist in a population of asthma and COPD patients, but that different MPB-components play a role in sick leave in asthma and COPD. Perceived control over health complaints is more important in asthma than in COPD. Attitudes towards sick leave appear to be more important in COPD patients.