A validated, 5‑question screening tool to evaluate asthma control in adults and adolescents (12+ years).Answer each question based on your experience over the past 4 weeks. Get instant results, a clear control-level classification,and actionable, evidence‑based recommendations to discuss with your healthcare provider.
The Asthma Control Test (ACT) is a clinically validated, patient‑reported outcome measure developed by researchers at the University of Toronto and endorsed by the Global Initiative for Asthma (GINA). It consists of five simple questions that assess key domains of asthma control: symptom frequency, activity limitation, nocturnal awakenings, reliever medication use, and self‑perceived control. The ACT has been extensively studied and is widely used in primary care, pulmonary clinics, and asthma research to guide treatment decisions.
ACT Score = Σ (Q1 + Q2 + Q3 + Q4 + Q5)
Each question scored 1–5, total range 5–25. Higher scores indicate better control.
Asthma is a chronic inflammatory airway disease affecting over 300 million people worldwide. Proper control assessment is essential to reduce exacerbations, improve quality of life, and prevent long‑term airway remodeling. The ACT provides a quick, reliable snapshot of control that correlates well with objective measures such as spirometry and fractional exhaled nitric oxide (FeNO). Studies have shown that an ACT score ≤ 19 is a strong predictor of future exacerbations, making this tool invaluable for both patients and clinicians.
The ACT is uniquely valuable because it captures the patient's perspective — an aspect often overlooked in purely objective assessments. It empowers individuals to recognize patterns in their symptoms and take proactive steps, such as adjusting medication or avoiding triggers, in partnership with their healthcare team.
The ACT score is divided into three clinically meaningful categories based on extensive validation studies:
A drop in ACT score by 3 or more points between visits is considered clinically significant and should prompt a review of adherence, inhaler technique, environmental triggers, and comorbidities such as allergic rhinitis or GERD.
The ACT was originally validated in a cohort of over 1,700 patients with asthma. Cronbach's alpha (internal consistency) was 0.85, and test‑retest reliability was excellent (r = 0.82). The ACT showed strong correlation with specialist assessment of control (r = 0.76) and discriminated well between patients with different levels of control as judged by pulmonologists. Subsequent studies have confirmed its utility across diverse populations, including children, adolescents, and adults, as well as in different healthcare settings.
A landmark study by Schatz et al. (2006) demonstrated that an ACT score ≤ 19 had a sensitivity of 71% and specificity of 71% for detecting uncontrolled asthma, making it a reliable screening tool. The ACT is now recommended by GINA as a core component of asthma assessment in both initial evaluation and ongoing monitoring.