Factors contributing to chronic obstructive pulmonary disease patients' functional performance: Structural equation modelling based on theory of unpleasant symptoms.

The severity of the disease, uncertainty, and symptom experience should be reduced to improve the functional performance of chronic obstructive pulmonary disease patients. Furthermore, reduced uncertainty can improve functional performance by reducing symptom experience. Nursing interventions for the improvement of pulmonary function and reduction of symptom experience should be developed.