Psychometrische Eigenschaften der deutschen Version des St. George's Respiratory Questionnaire im Kontext der stationären pneumologischen Rehabilitation

Abstract

PURPOSE: Health-related quality of life represents an important outcome parameter in the evaluation of the quality of results of medical rehabilitation. The St. George's Respiratory Questionnaire (SGRQ) was developed for measuring the disease-related limitations of health-related quality of life in patients with chronic respiratory diseases. In this article, the German version of the SGRQ is evaluated in the context of pneumological rehabilitation. MATERIALS AND METHODS: The following quality criteria of the test are examined: acceptance, value distribution, internal consistency, factorial structure, construct validity and sensitivity to change. The SGRQ was given to patients from 7 pneumological rehabilitation centres at the start, at the end, and 6 months after the end of rehabilitation. The analyses are based on data from n=647 patients. RESULTS: All scores of the SGRQ are internally consistent with a Cronbach's alpha >0.70. The confirmatory factor analysis does not satisfactorily confirm the recommended factorial structure of the German version of the SGRQ (χ 2 =5 298.06; df=986; p<0.001; CFI=0.539; GFI=0.625; RMSEA=0.087). The SGRQ “Symptoms” score correlates with the IRES [ INDICATORS OF REHABILITATION STATUS] dimension “Somatic Health” at r=0.50, the SGRQ “Activity” score with the IRES dimension “Activities of Daily Living” at a value of r=0.62, while the SGRQ “Impact” score and the IRES dimension “Activities of Daily Living” correlate at a value of r=0.73. Moreover, a correlation of r=0.42 can be determined between the SGRQ “Total Score” and the pulmonary-specific functional parameter FEV 1 . The short-term SRM effect sizes are 0.07 for the “Symptoms” score, 0.44 for the “Activity” score and 0.36 for the “Impact” score. In the medium-term, a size of 0.33 is found for the “Symptoms” score; as for the remaining scores, the sizes are between 0.25 and 0.37. CONCLUSIONS: The SGRQ is an internally consistent questionnaire for measuring health-related quality of life in pneumological rehabilitation patients. The SGRQ scores correlate with the corresponding IRES dimensions. It is also suitable for the measurement of changes. However, the factorial structure of the questionnaire could only be partially confirmed.