Validation of the Asthma Control Test questionnaire in a North African population.

Respir Med 2009 Dec;103 Suppl 2:S30-7

Medical Department, GlaxoSmithKline, Dubai.

Background: Patient-reported outcome measures are required to measure asthma control. The Asthma Control Test (ACT) is one such measure which was used in the AIRMAG study, a general population study of asthma in the Maghreb. Three dialectal Arabic versions of the ACT (Algerian, Moroccan and Tunisian) were developed.

Objective: To perform a psychometric evaluation of the properties of dialectal Arabic versions of the ACT used in the AIRMAG study.

Methods: The test data came from 624 adult subjects in a random general population sample in Algeria, Morocco and Tunisia. The internal consistency of the ACT was analysed using Cronbach's a coefficient. The factorial structure was explored by primary component analysis with varimax rotation. Test-retest reproducibility was assessed in a subgroup of 61 subjects. Face and discriminant validity were assessed.

Results: Cronbach's a coefficient ranged from 0.58 for the Algerian version to 0.67 for the Moroccan version. The 'use-of-rescue-treatment' item was identified as discordant, since its removal resulted in an increase in Cronbach's a coefficient. The discordance of this item was confirmed by primary component analysis, where the four remaining items were aligned along a single dimension, and the 'use-of-rescue-treatment' item offset along a second dimension. Test and retest scores were well correlated (r =0.704). The ACT showed good face and discriminant validity.

Conclusions: The ACT is a valid measure of asthma control in a North African context, although its internal consistency is compromised by the 'use-of-rescue-treatment' item, probably due to limited access to care and use of short-acting beta-agonists.

Download full-text PDF

Source
http://dx.doi.org/10.1016/S0954-6111(09)70025-3DOI Listing
December 2009
4 Reads

Publication Analysis

Top Keywords

asthma control
16
'use-of-rescue-treatment' item
12
cronbach's coefficient
12
primary component
8
dialectal arabic
8
north african
8
measure asthma
8
arabic versions
8
face discriminant
8
component analysis
8
general population
8
control test
8
internal consistency
8
algeria morocco
4
coefficient discordance
4
increase cronbach's
4
removal increase
4
tunisia internal
4
item confirmed
4
morocco tunisia
4

Similar Publications