title: Preliminary reliability study of the affective lability scale adapted for adolescents in a francophone clinical population.
abstract: OBJECTIVE
  to study the reliability of a self-questionnaire on adolescent affective instability, within a francophone clinical population.
  
  
  METHODS
  After reviewing the literature and consulting experts, the Affective Lability Scale (ALS), developed by Harvey and collaborators (1989), was selected. An anglophone and francophone version, adapted for the adolescent population, was developed. The final version includes 54 questions, divided into six sections, which examine the affective variations between euthymia, on the one hand, and depression, elation, and anxiety, on the other, and also examine the affective variations between anxiety and depression, and between depression and elation. The francophone version was the subject of a reliability study. A total of 43 francophone adolescents (48.8% male, 51.2% female; median age=14.86 years) took part in the comprehension and reliability study.
  
  
  RESULTS
  All questions were assigned a comprehension rate per item (CRI)>0.60 as evaluated by inter-rater agreement (median kappa=0.85). The median CRI is very satisfactory (0.88, SD=0.14). The internal consistency, determined by Cronbach coefficients, is elevated for each section and for the entire instrument (0.87 to 0.95). The temporal stability at three weeks is satisfactory, with an intraclass correlation coefficient (ICC) for the entire scale of 0.89 (confidence interval of 95%=0.75 to 0.95) and section's ICCs ranging between 0.72 and 0.89.
  
  
  CONCLUSIONS
  This initial reliability data supports interest in the ALS as a means to evaluate a global level of affective lability, during the euthymic phase, among francophone adolescents in an in-patient psychiatric unit. A future study with a larger sample will make it possible to confirm these initial results and examine the factorial structure of the instrument.
authors.affiliation: Clinique des Troubles de l'Humeur et Service de recherche, Hôpital Rivière-des-Prairies, Département de psychiatrie, Université de Montréal, Montréal, Quebec. jmguile@total.net
authors.forename: Jean Marc
authors.initials: JM
authors.lastname: Guilé
authors.forename: Cimon
authors.initials: C
authors.lastname: Chapdelaine
authors.forename: Lyne
authors.initials: L
authors.lastname: Desrosiers
authors.forename: Christine
authors.initials: C
authors.lastname: Cornez
authors.forename: Hélène
authors.initials: H
authors.lastname: Bouvier
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Breton