Anxiety disorders are the most common mental health conditions affecting both children and adolescents [1,2,3]. Many children with anxiety disorders are reportedly left untreated [3] and this influences their academic performance, interpersonal relationships, family relationships, social adjustment, and quality of life [4,5,6,7]. All anxiety disorders can impact adult functioning [8,9,10] and involve a high risk of other mental diseases, such as depression [11,12,13,14]. Therefore, efforts to design and implement prevention or early intervention programmes aimed at childhood anxiety problems are essential, due to the extraordinarily high social cost of anxiety and depression [15, 16].
The number of children who refuse to attend school is consistently increasing in Japan (e.g., over 140,000 in 2017) and teachers have a difficult time dealing with this issue. Preceding overseas studies have reported a relationship between anxiety and higher levels of school absenteeism among children [17,18,19]. Additionally, in Japan, the results of an annual survey of elementary and junior-high schoolteachers, conducted by the Ministry of Education, Culture Sports Science and Technology (MEXT), showed that ‘anxiety tendency’ was the most prevalentamong the subcategory of ‘factors related to the particular child’ as a cause of school absenteeism [20]. Thus, there is an urgent need for effective countermeasures to prevent school absenteeism among children with underlying anxiety problems.
School-based preventative approaches that target mental disorders may be approximately divided into two categories: targeted and universal approaches. While targeted approaches are aimed at high-risk children, universal approaches are for all children regardless of their individual risk status [21]. Universal prevention programmes in schools have various merits: wide reach, no screening, no stigma, enhanced mental health and reduction in presenting symptoms [22]. Conducting programme sessions during school hours is a preferred method because all children can receive mental and physical health education in their natural environment, thus making the school an appropriate location for preventive education programmes [23].
Recently, several meta-analyses were conducted comparing targeted versus universal approaches; they concluded that there was no significant difference between the two approaches [24,25,26]. Thus, it is appropriate and important to implement a high-quality preventive education programme with universal approach for children during their school hours, with the aim of preventing mental disorders.
The effectiveness of programmes dealing specifically with anxiety or depression of children has been supported by several systematic reviews [24, 25, 27,28,29,30,31,32]. Preventive programmes that have proven to be effective are mostly CBT based [30]. Originally, clinical evidence suggested CBT was effective as a treatment for patients with either anxiety or depression [33], but recently CBT is being implemented more as a preventive measure. Several systematic reviews reported that among all of the CBT-based universal preventive programmes, the FRIENDS programme developed by Doctor Barrett from Australia, was more effective than most other programmes [24, 28, 34]. As the World Health Organization (WHO) has recommended the FRIENDS, many studies have been conducted to verify its efficacy. However, to date, the results of these studies have been inconsistent, with their effect sizes varying substantially [37].
In England, Stallard et al. [23], reported a cluster randomised control trial (c-RCT) that implemented the FRIENDS in 41 elementary schools. A significant reduction in RCADS (the Revised Child Anxiety and Depression Scale) scores was only evident in the health-led (led by health professionals) group, with no significant difference found between the school-led and usual school curriculum groups (health-led vs. school-led, p = 0.0004, health-led vs. usual school provision, p = 0.043).
In Japan, two small scale intervention studies analysed the effectiveness of the FRIENDS programme as facilitated by school psychologists [35, 36]. Matsumoto and Shimizu [35] conducted a non-randomised trial, but the intervention group did not display significant score reduction, and the effect size was reported to be small. Kato and Shimizu [36] also did not find any significant effectiveness. Given these results, we developed the ‘Journey of the Brave’ programme (JOB) with the motivation that it is necessary to develop a programme that is effective even when it is facilitated by elementary school teachers in Japan. JOB considers the specific cultural and social backgrounds of Japanese children and matches the education system of Japan [37].
Before this study, we conducted two small-scale controlled trials [37, 38]. The pilot study involved 9–12 year-old children attending elementary schools that held ten weeks of JOB sessions at a community centre during after school hours [37]. A medium effect size was observed in Spence Children’s Anxiety Score (SCAS) in the intervention group of 13 children (parental evaluation) at 3-month follow-up (SCAS-P: change from baseline 9.709, 95% CI 5.79, 14.23, p = 0.0001). Subsequently, we conducted a second study targeting fifth-grade (10–11 years old) schoolchildren with a larger sample size (intervention group n = 31, control group n = 41) using classroom-based interventions in an elementary school. This study also found significant anxiety score reductions in the intervention group, with the effects again being maintained at 3-month follow-up [38].
Although both preceding studies demonstrated the feasibility and effectiveness of the JOB, they had various limitations; such as limited sample sizes and the fact that they were both facilitated by a member of the research group, not school personnel. To strengthen the evidence for the programme’s efficacy and to implement it in more schools, it became necessary to run the programme in a greater number of schools while using schoolteachers as facilitators. Thus, the objective of this study was to verify the effectiveness of the JOB when it is implemented in classrooms of elementary schools in various areas of Japan and facilitated by teachers; accordingly, we conducted a large-scale controlled trial.