title: The development of worry throughout childhood: Avon Longitudinal Study of Parents and Children data.
abstract: OBJECTIVE
  Anxiety is a normal part of childhood and adolescence; however, longitudinal research investigating the development of worrisome thoughts throughout childhood is lacking. This study investigated mothers' perspectives on their child's normal development of worry as the cognitive component of anxiety and its impact on child functioning in a longitudinal population-based cohort.
  
  
  METHODS
  The data for this study were extracted from the Avon Longitudinal Study of Parents and Children. Mothers (N = 2,227) reported on their child's worry content, frequency, control, emotional disruption, and interference when their child was 7, 10, and 13 years old using the parent component of the Development and Well-being Assessment. At age 10 and 13, pubertal status was assessed using children's self-report of pubic hair developmental progress.
  
  
  RESULTS
  Mothers reported a peak of worrisome thoughts at 10. Emotional disruption was highest at 10, and the highest level of interference in daily life was observed at 13, especially for girls. Advanced pubertal status and worry frequency were positively associated for boys at 10 and girls at 13. Advanced puberty at 10 was also associated with overall higher worry frequency and emotional disruption.
  
  
  CONCLUSIONS
  Findings are discussed within a developmental framework outlining the normal development of worrisome thoughts, associated distress, and interference throughout early adolescence. Increased knowledge of normative worry could be informative to further our understanding of adolescence as a vulnerable period for the development of mental health problems, such as generalized anxiety disorder.
  What is already known on this subject? Worrying is a normal part of childhood, making distinguishing between normal and pathological worrying challenging. Worry content remains consistent between age 4 and 7, but only for boys. The complexity and elaboration of worrisome thoughts increase from 8 years onwards. What does this study add? Worry frequency peaks at 10 and a low ability to control those worries can be observed at this age. The highest level of interference in performing daily activities due to worries is observed at age 13. Child sex and pubertal status play a role in understanding how normal worry patterns develop from age 10 onwards.
authors.affiliation: School of Psychology, NUI Galway, Ireland.
authors.forename: Line
authors.initials: L
authors.lastname: Caes
authors.affiliation: Centre for Pain Research, The University of Bath, UK.
authors.forename: Emma
authors.initials: E
authors.lastname: Fisher
authors.affiliation: Bristol Royal Children's Hospital, University of Bristol, UK.|Royal National Hospital for Rheumatic Diseases, Bath, UK.
authors.forename: Jacqui
authors.initials: J
authors.lastname: Clinch
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, UK.
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Tobias
authors.affiliation: Centre for Pain Research, The University of Bath, UK.
authors.forename: Christopher
authors.initials: C
authors.lastname: Eccleston
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001007:Anxiety / Q000523:psychology*; D002648:Child; D004644:Emotions; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009035:Mothers; D011627:Puberty / Q000523:psychology; D013315:Stress, Psychological / Q000523:psychology; D011795:Surveys and Questionnaires
keywords: anxiety; child development; emotional disruption; interference; worry