COPD Assessment Test (CAT)
| Name of questionnaire | COPD Assessment Test (CAT) |
| Type of questionnaire-description | Patient-completed questionnaire assessing globally the impact of COPD (cough, sputum, dysnea, chest tighteness) on health status |
| Number of items | 8 (one question assessing impact on sleep) |
| Number of domains & categories | Unidimensional |
| Name of categories/domains | N/A |
| Scaling of items | 1 to 5 |
| Scoring | Range of CAT scores from 0–40. Higher scores denote a more severe impact of COPD on a patient’s life. The difference between stable and exacerbation patients was five units. No target score represents the best achievable outcome. |
| Test-retest reproducibility | Reported, intra-class correlation coefficient=0.8 (P.W. Jones, G. Harding, P. Berry, I. Wiklund, W-H. Chen and N. Kline Leidy. Development and first validation of the COPD Assessment Test. Eur Respir J 2009, 34: 648–654). |
| Internal consistency | Reported Cronbach’s α=0.88 (P.W. Jones, G. Harding, P. Berry, I. Wiklund, W-H. Chen and N. Kline Leidy. Development and first validation of the COPD Assessment Test. Eur Respir J 2009, 34: 648–654) |
| Validity | High correlation with SGRQ (r=0.84) across 7 European countries (Jones PW, Brusselle G, Dal Negro RW, Ferrer M, Kardos P, Levy ML, et al. Properties of the COPD assessment test in a cross-sectional European study. European Respiratory Journal. 2011 July 1, 2011;38(1):29-35.) and r=0.8 in US. (P.W. Jones, G. Harding, P. Berry, I. Wiklund, W-H. Chen and N. Kline Leidy. Development and first validation of the COPD Assessment Test. Eur Respir J 2009, 34: 648–654) |
| Minimally important difference | Not determined. Mapping against SGRQ suggests MCID at a group level is 1.6. Experts also suggest that scores <10 have a low impact, 10-20 medium, 21-30 high and >30 very high impact, requiring gradually more interventions (Click Here). |
| Language | English for UK and the USA |
| Translations in other languages (if yes, then list the languages) | Available in 57 other languages; for an up-to-date list, Click Here |
| Developer name | Paul W. Jones, G. Harding, P. Berry, I. Wiklund, W-H. Chen and N. Kline Leidy |
| Developer contact information | Paul W. Jones Division of Cardiac and Vascular Science St George’s University of London Cranmer Terrace, London, SW17 0RE, UK E-mail: pjones@sgul.ac.uk |
| Availability of questionnaire: needs permission from developer, cost or freely available | GlaxoSmithKline is the copyright owner of the (CAT). Can find contact information for your country if you Click Here. |
| References (original publication) | P.W. Jones, G. Harding, P. Berry, I. Wiklund, W-H. Chen and N. Kline Leidy. Development and first validation of the COPD Assessment Test. Eur Respir J 2009, 34: 648–654. |
| Limitations | Clinically important minimal difference remains to be rigorously studied |
| Link to the questionnaire (if available) | Click Here |
| Other comments | - |
| Alternate versions | none |
