Use of factor analysis to consolidate multiple outcome measures in chronic obstructive pulmonary disease.

[1]  C. Bucca,et al.  A multivariate analysis of the risk in chronic obstructive lung disease (COLD). , 1985, Journal of chronic diseases.

[2]  G. Borg.  Psychophysical bases of perceived exertion. , 1982, Medicine and science in sports and exercise.

[3]  R. Kanner,et al.  Pathologic patterns of chronic obstructive pulmonary diseases in patients with normal and deficient levels of alpha 1 antitrypsin. , 1973, The American journal of medicine.

[4]  J. Morris,et al.  Spirometric standards for healthy nonsmoking adults. , 2015, The American review of respiratory disease.

[5]  E. B. Andersen,et al.  Modern factor analysis , 1961 .