title: Development and testing of the modified version of the pulmonary functional status and dyspnea questionnaire (PFSDQ-M).
abstract: OBJECTIVE
  Describe the process of development and testing to reduce the Pulmonary Functional Status and Dyspnea Questionnaire (PFSDQ) from 164 items to a modified questionnaire (the PFSDQ-M) consisting of 40 items.
  
  
  METHODS
  Instrument development and testing for reliability, validity, and practicality.
  
  
  METHODS
  Hospital-based outpatients.
  
  
  METHODS
  Testing was done on three groups of clinically stable patients with chronic obstructive pulmonary disease: a secondary analysis of 131 subjects for item selection, reliability, and validity; 50 additional subjects evaluating the PFSDQ-M for internal consistency, test-retest correlations, and construct validity; and 34 subjects from a longitudinal study for responsiveness.
  
  
  METHODS
  PFSDQ, PFSDQ-M, and spirometry.
  
  
  RESULTS
  The practicality of the PFSDQ-M was supported by its sixth- to seventh-grade reading level, ease of reading (Flesch-Kincaid 69.5), self-administration, brief period for testing (7 minutes initially, 6 minutes on repeated testing), and limited missing data (< 8%). Reliability of the three components was supported by internal consistency alpha = 0.93 for change experienced by the patient with activities (CA), 0.95 for dyspnea with activities (DA), and 0.95 for fatigue with activities (FA). Good stability of the PFSDQ-M was demonstrated on test-retest; r = 0.70 for change, 0.83 for dyspnea, and 0.79 for fatigue (with activities). The usefulness of the PFSDQ-M in discriminating between dyspnea scores in patients based on their rate of deterioration in lung function was demonstrated.
  
  
  CONCLUSIONS
  The PFSDQ was modified by reducing the number of activities evaluated, standardizing scaling formats, and adding a fatigue component. Findings suggest that the PFSDQ-M demonstrates initial reliability; good validity estimates, as seen with the factor analysis, and the dyspnea and activity scores appear responsive to physiologic changes in lung function over time.
authors.affiliation: Jerry L. Pettis Veterans Administration Medical Center, Department of Medicine, Loma Linda University, Calif 92357, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Lareau
authors.forename: P M
authors.initials: PM
authors.lastname: Meek
authors.forename: P J
authors.initials: PJ
authors.lastname: Roos
mesh_terms: D000203:Activities of Daily Living / Q000145:classification; D000368:Aged; D000553:Ambulatory Care; D004417:Dyspnea / Q000145:classification / Q000209:etiology*; D005221:Fatigue / Q000145:classification / Q000209:etiology; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008137:Longitudinal Studies; D008173:Lung Diseases, Obstructive / Q000145:classification / Q000175:diagnosis* / Q000534:rehabilitation; D008297:Male; D008487:Medical History Taking / Q000706:statistics & numerical data*; D008875:Middle Aged; D015203:Reproducibility of Results; D013147:Spirometry / Q000706:statistics & numerical data*; D011795:Surveys and Questionnaires