BACKGROUND: Early identification of acute exacerbations of COPD facilitates better care. This study was designed to validate a short questionnaire (Exascore) developed to help patients, relatives and carers to diagnose acute exacerbations.
METHOD: We first addressed content validity that allowed the elaboration of two questionnaires, one assessing the current status and the other stable status (transition). The second step tested their construction validity, reproducibility and concomitant validity among 126 COPD patients aged 64.4±9.9 years. They included 56 presenting with an exacerbation and 70 in stable state, of whom 57 completed the questionnaire a second time after 7 days. The diagnosis of exacerbation and assessment of severity (gold standard) were established by the treating respiratory physician and confirmed by two independent experts.
RESULTS: Factorial analyses established a "current status" questionnaire comprising 8 items and 2 dimensions. Cronbach's alpha coefficients were satisfactory, 0.867 for "respiratory impact", 0.886 for "psychosocial impact" and 0.886 for the total score. Concomitant validity and reproducibility were also adequate. The transition questionnaire did not obtain convincing psychometric results.
CONCLUSIONS: The "current status" Exascore questionnaire satisfies psychometric quality criteria while being usable in clinical practice. It helps in diagnosing acute exacerbations and assessing their intensity. Further studies will need to test the adequacy of proposed thresholds, the factorial structure of the score in healthcare professionals and patients' relatives, and its predictive power.