Validation of the Brazilian Portuguese version of the University of California San Diego Shortness of Breath Questionnaire in patients with interstitial lung disease

Our plain-English summary of Validation of the Brazilian Portuguese version of the University of California San Diego Shortness of Breath Questionnaire in patients with interstitial lung disease, by H. Silva, L.C. Mantoani, C.L. Zamboti, et al (Jornal Brasileiro de Pneumologia, 2021).

The study

• Authors: H. Silva, L.C. Mantoani, C.L. Zamboti, W.F. Aguiar, A.L. Ries, A.F.L. Gonçalves, T.G.D. Silva, M. Ribeiro, F. Pitta, C.A. Camillo
• Journal: Jornal Brasileiro de Pneumologia
• Published: 2021;47(6):e20210172
• Language: Portuguese
• Cited by: 4 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Objective: To investigate the reliability, internal consistency and validity of the Brazilian Portuguese version of the University of California San Diego Shortness of Breath Questionnaire (UCSD SOBQ) in patients with interstitial lung disease (ILD).

Methods: Patients with ILD completed the questionnaire at three different time points, one week apart, with the assistance of two independent assessors. Intra- and inter-rater reliability were analysed via the intraclass correlation coefficient (ICC). Internal consistency was assessed with the Cronbach's alpha coefficient. For the validity analysis, associations between variables were assessed with Spearman's or Pearson's correlation coefficient.

Results: Thirty patients with ILD (idiopathic pulmonary fibrosis, connective tissue disease-associated pulmonary fibrosis, sarcoidosis, asbestosis or non-specific interstitial pneumonia) were included (15 men; mean age, 59 ± 10 years; DLCO: 46 [33-64] % predicted). UCSD SOBQ scores showed excellent agreement and internal consistency in the intra-rater analysis (ICC: 0.93 [0.85-0.97]; Cronbach alpha: 0.95) and in the inter-rater analysis (ICC: 0.95 [0.89-0.97]; Cronbach alpha: 0.95), as well as correlating significantly with dyspnoea (as assessed by the Medical Research Council scale; r = 0.56); Medical Outcomes Study 36-item Short-Form Health Survey domains bodily pain, general health, vitality and physical functioning (-0.40 ≤ r ≤ -0.74); six-minute walk distance (r = -0.38); and quadriceps muscle strength (r = -0.41).

Conclusions: The Brazilian Portuguese version of the UCSD SOBQ is valid, is reliable and has internal consistency in patients with ILD in Brazil.

In plain English

This cross-sectional study in Londrina, Brazil, tested a Brazilian Portuguese version of the University of California San Diego Shortness of Breath Questionnaire (UCSD SOBQ) in people with interstitial lung disease. The questionnaire rates breathlessness during daily activities. Thirty patients took part: 18 with idiopathic pulmonary fibrosis, 5 with connective tissue disease-associated pulmonary fibrosis, 4 with particle-induced pulmonary fibrosis and 3 with non-specific interstitial pneumonia. The study did not examine asbestos exposure. An interviewer read the questionnaire to each patient at three visits up to 7 days apart, and two different interviewers took part. Agreement was rated excellent: the intraclass correlation coefficient was 0.93 (interval 0.85 to 0.97) for the same interviewer and 0.95 (0.89 to 0.97) between interviewers. Scores correlated with a breathlessness scale (r = 0.56), several quality-of-life domains (r from -0.40 to -0.74), walking distance (r = -0.38) and quadriceps strength adjusted for body weight (r = -0.41). They did not correlate significantly with lung function. The authors concluded that this version is valid and reliable in these patients. They noted a small single-centre sample, and self-completion was not tested.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: cross-sectional validation study of a questionnaire (repeated administration to test reliability, correlations with other measures to test validity)
• Who was studied: 30 outpatients with interstitial lung disease from a university hospital clinic in Londrina, Brazil: 18 idiopathic pulmonary fibrosis, 5 connective tissue disease-associated pulmonary fibrosis, 4 particle-induced pulmonary fibrosis, 3 non-specific interstitial pneumonia; 15 men; mean age 59 years. Study dates are not given.
• Exposure: No asbestos or other exposure was studied. The study assessed a breathlessness questionnaire, not an exposure.
• Main results:
  • Total UCSD SOBQ scores did not differ significantly across the three visits (visit 1: 39 plus or minus 23; visit 2: 42 plus or minus 24; visit 3: 37 plus or minus 21; p = 0.07)
  • Same-interviewer (visit 1 vs visit 3) reliability: ICC 0.93 (0.85 to 0.97), Cronbach's alpha 0.95
  • Between-interviewer (visit 1 vs visit 2) reliability: ICC 0.95 (0.89 to 0.97), Cronbach's alpha 0.95
  • UCSD SOBQ scores correlated with Medical Research Council breathlessness scale scores (r = 0.56, p = 0.0019)
  • UCSD SOBQ scores correlated negatively with the SF-36 domains physical functioning, bodily pain, general health and vitality (r from -0.40 to -0.74). Correlations with the role-physical, role-emotional, social functioning and mental health domains were not significant.
  • UCSD SOBQ scores correlated with quadriceps muscle strength adjusted by body weight (r = -0.41, p = 0.03) and with six-minute walk distance in metres (r = -0.38, p = 0.03)
  • Correlations with lung function measures were all non-significant (r between -0.12 and 0.25, p greater than 0.05 for all)
  • No patients scored in the most severe 10% of scores (ceiling effect 0%). 3% scored in the least severe 10% (floor effect).
• The authors' conclusion: The authors concluded that, despite the relatively small sample, the Brazilian Portuguese UCSD SOBQ is a valid and reliable instrument for assessing breathlessness related to daily activities in patients with interstitial lung disease, and that different assessors can apply it.
• Limitations the authors state:
  • Small sample size from a single centre
  • The questionnaire was administered by interviewers although it was designed for self-completion. Whether the self-administered version is valid and reliable remains to be confirmed.

Topics

Medical terms in this study, explained in our Lexicon: Interstitial Lung Disease, Idiopathic, Pulmonary Fibrosis, Interstitial, Diffusing Capacity (DLCO), Six-Minute Walk Test.

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