Development and validation of the RAND Asthma Control Measure

Area of Science:

• Pulmonary Medicine
• Health Outcomes Research
• Psychometrics

Background:

• Asthma is a prevalent chronic illness with significant global impact.
• Patient-based measures are crucial for assessing asthma control.
• Existing measures require refinement to align with updated definitions and improve usability.

Purpose of the Study:

• To refine and further validate a previously developed asthma symptom scale.
• To create a shorter, more current measure reflecting international expert definitions of asthma control.
• To introduce the RAND Asthma Control Measure (RAND-ACM).

Main Methods:

• Rigorous psychometric testing of new and adapted self-administered survey items.
• Utilized a large sample of 2032 adults with asthma.
• Assessed reliability, validity, and internal consistency (Cronbach's α = 0.84).

Main Results:

• The RAND Asthma Control Measure (RAND-ACM) demonstrated reliability and preliminary validity comparable to or exceeding existing measures.
• Worse RAND-ACM scores correlated with poorer quality of life, increased healthcare use, and demographic factors (Hispanic ethnicity, lower education).
• Adequate concordance was found between RAND-ACM scores and Global Initiative for Asthma categories.

Conclusions:

• The RAND-ACM is a well-performing, five-item self-reported measure for asthma control in a diverse US adult population.
• It serves as a cost-free alternative to other available asthma control assessment tools.
• The RAND-ACM is valuable for assessing asthma control and its impact on patients' lives.