Development of the LAQ-6: a questionnaire for assessing long-term asthma control.

Abstract

Existing asthma questionnaires rely on short recall periods and may not capture symptom burden across typical follow-up intervals. A brief instrument that summarizes longer-term asthma control may support risk stratification and remission-oriented care. To develop a brief questionnaire that assesses symptom burden over a 3-month recall period and evaluate its performance in identifying ACT-defined well-controlled asthma. Ninety adults with asthma completed our questionnaire, the 6-item Long-term Asthma Control Questionnaire (LAQ-6), and the Asthma Control Test (ACT) in an outpatient setting. Correlation and receiver operating characteristic curve (ROC) analyses were performed to evaluate associations with ACT-defined well-controlled status (ACT ≥20). Confirmed exacerbations and emergency visits over an approximately 6-month observation window were assessed using ROC analyses and prespecified cutoffs. The LAQ-6 strongly correlated with the ACT (r = 0.79, P < .001) and asthma-related quality of life assessed using mean Asthma Quality of Life Questionnaire scores (Spearman's rho = 0.763, P < .001). It achieved an area under the curve (AUC) of 0.83 in identifying ACT-defined well-controlled status (ACT ≥20) (95% confidence interval, 0.72-0.94). For 6-month outcomes, the LAQ-6 achieved higher AUCs than the ACT for exacerbations (0.866 vs. 0.816) and emergency visits (0.857 vs. 0.676). Exacerbations and emergency visits were more frequent in patients with LAQ-6 scores below the prespecified cutoff (<27). The LAQ-6 is a brief 3-month recall questionnaire complementing existing short-recall tools. It may facilitate rapid assessment of longer-term symptom burden and risk stratification in outpatient practice, supporting evaluation of clinical remission.