Development and validation of the COugh Assessment Test (COAT)

Respirology. 2019 Jun;24(6):551-557. doi: 10.1111/resp.13462. Epub 2019 Jan 25.

Abstract

Background and objective: A cough-specific quality-of-life questionnaire is recommended to assess the impact of cough; however, a simple instrument to quantify cough is required for everyday clinical practice. This study was aimed to develop a short patient-completed questionnaire (COugh Assessment Test, COAT).

Methods: The COAT was developed and validated by comparison with the Korean version of Leicester Cough Questionnaire (K-LCQ) and cough numeric rating scale (NRS, 0-10, 11-point scale) for chronic cough patients.

Results: Item selection identified five items regarding cough frequency, daily activity, sleep disturbance, fatigue and cough hypersensitivity (0-4 scaling of items, 0-20 score range) through reliability test cohort (n = 78). Test-retest reliability was strong (intra-class correlation coefficient = 0.88). The final COAT was compared with K-LCQ and cough NRS in a validation cohort (n = 323). In Rasch analysis, COAT fitted well to a unidimensional model. Pearson correlations of COAT versus K-LCQ (i) before treatment, (ii) after treatment; COAT versus cough NRS (iii) before treatment, (iv) after treatment; (v) delta-COAT versus delta-cough NRS, (vi) delta-COAT versus delta-K-LCQ were (i) -0.71, (ii) -0.81, (iii) 0.69, (iv) 0.82, (v) -0.66 and (vi) 0.72, respectively.

Conclusion: The COAT is a useful, simple questionnaire for assessing and monitoring cough.

Keywords: cough; questionnaire; reliability; severity; validity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activities of Daily Living
  • Adult
  • Aged
  • Chronic Disease
  • Cough / complications*
  • Cough / psychology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Quality of Life*
  • Reproducibility of Results
  • Surveys and Questionnaires*