Prevention of Childhood Anxiety Disorders in Offspring of Anxious Parents

RESEARCH QUESTIONS * Is the CPBC-program effective in preventing childhood anxiety disorders within a period of 12 and 36 months respectively, compared to a self-help parenting book? * Is the CPBC-program effective in preventing childhood anxiety symptoms within a period of 12 and 36 months respectively, compared to a self-help parenting book? * Is the effect moderated by severity of parental anxiety, child anxiety symptoms at baseline, or gender or age of the child? * Is the study effective in increasing parental self efficacy? * Is the effect of CPBC-program mediated by changes in parental criticism and rejection, overprotection, parental modelling of anxiety or parental accommodation? * Is the CPBC-program cost-effective? DESIGN The first study is a full scale parallel randomised controlled trial (allocation ratio 1:1). This study will include follow-up assessments after 12 and 36 months and will evaluate the relative efficacy of the CPBC-program versus an active control group (self-help book). The second part includes a mediation analysis and the third part is a within trial economic evaluation comparing the outcomes and costs between the CPBC-program and control using two types of analyses (cost-utility analysis and cost-consequence analysis). POWER To have an 80% power to detect a significant (p ≤ 0.05) small to moderate difference (standardised mean difference = 0.4) the investigators will need to recruit 194 children. Given an anticipated attrition of 10%, the investigators will aim at including a total of 216 children. Participants will be recruited through advertisements. The participants will be randomly allocated to either (1) CPBC-program or (2) reading a self-help book.