D1.177 - Turkish Validity and Reliability of the Medication Adherence Report Scale for Asthma (MARS-A) in Adolescents with Asthma

Asthma is the most common chronic respiratory disease in childhood and represents a significant global health burden. Adherence to inhaled controller therapy is essential for achieving optimal asthma control and preventing exacerbations. The Medication Adherence Report Scale for Asthma (MARS-A) is a 10-item self-report instrument developed to assess adherence to inhaled medications and has been validated in several languages. However, a validated Turkish version for adolescents is lacking. This study aimed to evaluate the validity and reliability of the Turkish version of MARS-A in adolescents with asthma.

This single-center prospective study was conducted at the Pediatric Allergy and Immunology Clinic of Ankara Bilkent City Hospital. Adolescents aged 12–18 years with asthma diagnosed according to Global Initiative for Asthma (GINA) criteria were included. Based on the recommendation of at least 10 participants per item, 100 patients were enrolled. Asthma control was assessed using the Asthma Control Test (ACT), followed by administration of the Turkish MARS-A. The cross-cultural adaptation process included forward–backward translation, expert review, and pilot testing. Internal consistency was evaluated using Cronbach’s alpha and item–total correlations. Construct validity was assessed using Exploratory Factor Analysis (EFA), and criterion validity was examined through correlation with ACT scores.

The mean age of participants was 13.83 ± 2.02 years, and 58% were male. The Cronbach’s alpha coefficient was 0.729, indicating acceptable internal consistency. Item–total correlations ranged from 0.264 to 0.589. The Kaiser–Meyer–Olkin value was 0.713 and Bartlett’s test was significant (p<0.001), confirming suitability for factor analysis. EFA identified a three-factor structure explaining 58.82% of the total variance, with factor loadings between 0.496 and 0.788. MARS-A scores showed a significant positive correlation with ACT scores (r=0.385; p<0.001).

The Turkish version of MARS-A demonstrated acceptable validity and reliability in adolescents with asthma. Further confirmatory factor analysis in larger and independent samples is warranted.