TY - JOUR

T1 - Validation of the IPF-specific version of St. George's Respiratory Questionnaire

AU - Prior, Thomas Skovhus

AU - Hoyer, Nils

AU - Shaker, Saher Burhan

AU - Davidsen, Jesper Rømhild

AU - Yorke, Janelle

AU - Hilberg, Ole

AU - Bendstrup, Elisabeth

PY - 2019/8

Y1 - 2019/8

N2 - Background: Patients with idiopathic pulmonary fibrosis (IPF) have impaired health-related quality of life (HRQL). To measure HRQL, an IPF-specific version of the St. George's Respiratory Questionnaire (SGRQ-I) was developed, but not sufficiently validated. This study aimed to assess the validity (i.a. known-groups validity and concurrent validity) and test-retest reliability of SGRQ-I in IPF patients with different disease durations. Methods: Patients with IPF were consecutively recruited and completed SGRQ, SGRQ-I, King's Brief Interstitial Lung Disease questionnaire (K-BILD), University of California, San Diego Shortness of Breath Questionnaire (SOBQ) and Short Form-36 (SF-36) along with pulmonary function tests and a 6-min walk test (6MWT) at baseline. After two weeks, SGRQ-I and Global Rating of Change Scales (GRCS) were completed. Results: At baseline and after two weeks, 150 and 134 patients completed the questionnaires, respectively. The internal consistency of SGRQ-I was high (Cronbach's α = 0.92). Good concurrent validity was demonstrated by high intraclass correlation coefficients (ICC = 0.97), Bland-Altman plots and moderate to strong correlations to K-BILD, SOBQ and SF-36 (r = - 0.46 to 0.80). High ICC (0.92) and a Bland-Altman plot indicated good test-retest reliability. SGRQ-I was good at discriminating between patients with different stages of disease (Δscore > 18.1, effect sizes > 0.10). Validity was similar across groups of different disease duration. Conclusions: SGRQ-I proved to be valid at distinguishing between different disease severities, valid compared to other HRQL instruments, applicable across different disease durations and reliable upon repetition. SGRQ-I is a valid option for measuring HRQL in patients with IPF. Trial registration: The study was registered at clinicaltrials.org (NCT02818712) on 15 June 2016.

AB - Background: Patients with idiopathic pulmonary fibrosis (IPF) have impaired health-related quality of life (HRQL). To measure HRQL, an IPF-specific version of the St. George's Respiratory Questionnaire (SGRQ-I) was developed, but not sufficiently validated. This study aimed to assess the validity (i.a. known-groups validity and concurrent validity) and test-retest reliability of SGRQ-I in IPF patients with different disease durations. Methods: Patients with IPF were consecutively recruited and completed SGRQ, SGRQ-I, King's Brief Interstitial Lung Disease questionnaire (K-BILD), University of California, San Diego Shortness of Breath Questionnaire (SOBQ) and Short Form-36 (SF-36) along with pulmonary function tests and a 6-min walk test (6MWT) at baseline. After two weeks, SGRQ-I and Global Rating of Change Scales (GRCS) were completed. Results: At baseline and after two weeks, 150 and 134 patients completed the questionnaires, respectively. The internal consistency of SGRQ-I was high (Cronbach's α = 0.92). Good concurrent validity was demonstrated by high intraclass correlation coefficients (ICC = 0.97), Bland-Altman plots and moderate to strong correlations to K-BILD, SOBQ and SF-36 (r = - 0.46 to 0.80). High ICC (0.92) and a Bland-Altman plot indicated good test-retest reliability. SGRQ-I was good at discriminating between patients with different stages of disease (Δscore > 18.1, effect sizes > 0.10). Validity was similar across groups of different disease duration. Conclusions: SGRQ-I proved to be valid at distinguishing between different disease severities, valid compared to other HRQL instruments, applicable across different disease durations and reliable upon repetition. SGRQ-I is a valid option for measuring HRQL in patients with IPF. Trial registration: The study was registered at clinicaltrials.org (NCT02818712) on 15 June 2016.

KW - Health-related quality of life

KW - Idiopathic pulmonary fibrosis

KW - Interstitial lung disease

KW - IPF-specific version of the St. George's respiratory questionnaire

KW - K-BILD

KW - Quality of life

KW - SGRQ

KW - SGRQ-I

U2 - 10.1186/s12931-019-1169-9

DO - 10.1186/s12931-019-1169-9

M3 - Journal article

C2 - 31462235

AN - SCOPUS:85071622006

VL - 20

JO - Respiratory Research (Print)

JF - Respiratory Research (Print)

SN - 1465-9921

M1 - 199

ER -