Mass hysteria attack rates in children and adolescents: a meta-analysis

There are few systematic assessments of mass hysteria (MH) attack rates (ARs) in adolescents and children. The study aim was to assess the ARs of MH in this population.

We used a meta-analysis to systematically review studies and assess ARs.

The reviewed studies included 32,887 participants, of which 2968 were children and adolescents with a history of MH. Twenty-eight studies were included, of which 22 (78.6%) had high to moderate methodological quality. The pooled AR of MH was 9.8% (95% confidence interval [CI] 6.3, 14.0). Of MH studies between 2010 and 2020, 78.6% were conducted between 2010 and 2014. ARs were higher between 2010 and 2014 (10.3%) than between 2015 and 2020 (8.1%). Regarding population characteristics, the AR in girls was 2.43 (95% CI 1.70, 3.46) times higher than in boys. Most studies were on primary school students (46.4%), who showed the highest AR (15.4%). Of six trigger factors, water pollution showed the highest AR (16.3%). ARs were higher in rural areas (11.1%) than in urban areas (5.6%).

MH in children and adolescents seems prevalent and shows some epidemiological characteristics. These findings may assist governments to control and prevent MH epidemics among children and adolescents.