title: Effect on health-related quality of life of changes in mental health in children and adolescents.
abstract: BACKGROUND
  The objective of the study was to assess the effect of changes in mental health status on health-related quality of life (HRQOL) in children and adolescents aged 8 - 18 years.
  
  
  METHODS
  A representative sample of Spanish children and adolescents aged 8-18 years completed the self-administered KIDSCREEN-52 questionnaire at baseline and after 3 years. Mental health status was measured using the Strengths and Difficulties Questionnaire (SDQ). Changes on SDQ scores over time were used to classify respondents in one of 3 categories (improved, stable, worsened). Data was also collected on gender, undesirable life events, and family socio-economic status. Changes in HRQOL were evaluated using effect sizes (ES). A multivariate analysis was performed to identify predictors of poor HRQOL at follow-up.
  
  
  RESULTS
  Response rate at follow-up was 54% (n = 454). HRQOL deteriorated in all groups on most KIDSCREEN dimensions. Respondents who worsened on the SDQ showed the greatest deterioration, particularly on Psychological well-being (ES = -0.81). Factors most strongly associated with a decrease in HRQOL scores were undesirable life events and worsening SDQ score.
  
  
  CONCLUSIONS
  Changes in mental health status affect children and adolescents' HRQOL. Improvements in mental health status protect against poorer HRQOL while a worsening in mental health status is a risk factor for poorer HRQOL.
authors.affiliation: Catalan Agency for Health Technology Assessment and Research (CAHTA), Roc Boronat 81-95 2nd Floor, Barcelona, Spain. lrajmil@aatrm.catsalut.cat
authors.forename: Luis
authors.initials: L
authors.lastname: Rajmil
authors.forename: Jorge A
authors.initials: JA
authors.lastname: Palacio-Vieira
authors.forename: Michael
authors.initials: M
authors.lastname: Herdman
authors.forename: Sílvia
authors.initials: S
authors.lastname: López-Aguilà
authors.forename: Ester
authors.initials: E
authors.lastname: Villalonga-Olives
authors.forename: Josep M
authors.initials: JM
authors.lastname: Valderas
authors.forename: Mireia
authors.initials: M
authors.lastname: Espallargues
authors.forename: Jordi
authors.initials: J
authors.lastname: Alonso
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008016:Life Change Events; D008297:Male; D008603:Mental Health; D000297:Psychology, Adolescent; D002666:Psychology, Child; D011594:Psychometrics / Q000295:instrumentation; D011788:Quality of Life / Q000523:psychology*; D012044:Regression Analysis; D012307:Risk Factors; D012737:Sex Factors; D012923:Social Class; D013030:Spain; D011795:Surveys and Questionnaires