title: Comparative study of two quality of life questionnaires in patients with COPD.
abstract: OBJECTIVE
  To compare two quality of life questionnaires-the Saint George's Respiratory Questionnaire (SGRQ) and the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36)-in patients with COPD, focusing on the discriminative properties of the questionnaires and correlating their domains with the following variables: Modified Medical Research Council Dyspnea Scale score; Beck Depression Inventory score; visual analog scale general health perception; Mini-Mental State Examination score; and a COPD clinical score developed specifically for the study.
  
  
  METHODS
  We interviewed 30 COPD patients between May and September of 2006. For the SF-36 and SGRQ, scores (total and domain) were compared and correlated.
  
  
  RESULTS
  With the exception of the pain domain, all of the SF-36 domains correlated significantly with the SGRQ total score (r = -0.5 to -0.69; p < 0.01). Of the SGQR domains, only the symptoms domain correlated significantly with all of the variables studied (p < 0.05).
  
  
  CONCLUSIONS
  The majority of the expected correlations between the SGRQ and the SF-36 were observed, as were those expected between the two questionnaires and the other variables studied. The SGRQ, notably the symptoms domain, presented better discriminative properties than did the generic SF-36 questionnaire. The SF-36 is not an appropriate instrument for determining the affective state of COPD patients.
authors.affiliation: Pulmonary Function Laboratory, Pereira Filho Ward, Santa Casa Hospital Complex in Porto Alegre, Porto Alegre, Brazil. deabuss@yahoo.com.br
authors.forename: Andréa Sória
authors.initials: AS
authors.lastname: Buss
authors.forename: Luciano Müller Correa da
authors.initials: LM
authors.lastname: Silva
mesh_terms: D000203:Activities of Daily Living; D003866:Depressive Disorder / Q000503:physiopathology; D004185:Disability Evaluation; D004417:Dyspnea / Q000503:physiopathology; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000473:pathology / Q000503:physiopathology*; D011788:Quality of Life; D012720:Severity of Illness Index; D012907:Smoking / Q000009:adverse effects; D011795:Surveys and Questionnaires / Q000592:standards*