Cross-cultural adaptation and preliminary psychometric properties of the Affective Reactivity Index in Brazilian Youth: implications for DSM-5 measured irritability.
OBJECTIVE
To describe the cross-cultural adaptation of the Affective Reactivity Index (ARI) to Brazilian Portuguese and to investigate preliminary psychometric properties of the adapted version.


METHODS
Cross-cultural adaptation was based on the investigation of the theoretical and operational equivalences of the original ARI in the Brazilian context, followed by a process of translation, back-translation, and review by a committee of experts. Data analysis was carried out in a community sample of 133 schoolchildren aged 8 to 17 years to investigate the following characteristics of the ARI: 1) factor structure; 2) internal consistency; 3) construct validity comparing differential relationships between irritability and anxiety dimensions and impairment; and 4) item response theory (IRT) parameters.


RESULTS
A final Brazilian Portuguese version of the instrument was defined and is presented. Internal consistency was good, and our analysis supported the original single-factor structure of the ARI. Correlations of the ARI with distress-related anxiety dimensions were higher than with phobic-related anxiety dimensions, supporting its construct validity. In addition, higher ARI scores were associated with higher irritability-related impairment. IRT analysis underscored frequency of loss of temper as essential to inform about pathological states of irritability.


CONCLUSIONS
The Brazilian Portuguese version of the ARI seems to be very similar to the original instrument in terms of conceptual, item, semantic, and operational equivalence. Our preliminary analysis replicates and extends previous evidence confirming promising psychometric properties for the ARI.
Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Diogo Araújo
DA
DeSousa
Institute of Psychiatry, King's College London, London, United Kingdom.
Argyris
A
Stringaris
Section on Bipolar Spectrum Disorders, Emotion and Development Branch, National Institute of Mental Health, Bethesda, MD, USA.
Ellen
E
Leibenluft
UFRGS, Porto Alegre, RS, Brazil.
Silvia Helena
SH
Koller
UFRGS, Porto Alegre, RS, Brazil.
Gisele Gus
GG
Manfro
UFRGS, Porto Alegre, RS, Brazil.
Giovanni Abrahão
GA
Salum