The effect of peer education based on adolescent health education on the resilience of children and adolescents: A cluster randomized controlled trial

The Healthy China Action (2019–2030) plan explicitly mentions initiatives to promote mental health and student health [25]. However, although the government has introduced important policies and paid more attention to mental health, more research and guidance are needed to build an interrelated and efficient mental health system [2]. A large number of previ- ous studies have found that traditional health education in school classroom can effectively promote mental health such as resilience, anxiety and depression [12, 26, 27], and health risk behaviors such as smoking, alcohol abuse and unintentional injury [28–30], but the effect is incomplete and often short-term. Schools are key places to improve adolescent health, but classroom education is also challenging as schools increasingly focus on indicators of academic achievement [31]. After puberty, adolescents spend more time with their peers and have a stronger sense of identity with their peers [32], which suggests that peer education may be an effective way to improve the mental health of Chinese adolescents. Peer education is defined as “sharing experiences and learning among those of a similar age, living environment, and culture with something” [33], which is based on social cognitive theory [34] that shows that the interactions and observations of others can impact the behavior and attitude of individuals. A large number of studies have shown that peer education is extremely effective in some domains, such as prevention of chronic diseases and dissemination

of sexual knowledge [33, 35, 36]. This suggests that it is of great practical significance to adopt the method of peer education to intervene the resilience of Chinese adolescents. In most previ- ous clinical trials, participants were randomized as individuals to receive different interven- tions. However, it is worth noting that sometimes individual assignment is not possible or desirable. Indeed, many educational evaluations are conducted in naturally occurring clusters (such as classes or schools), and the only practical way to conduct a randomized controlled trial (RCT) is to use cluster assignment. Cluster randomization is often used to avoid contami- nation between those who receive intervention and those who do not [37]. Using clusters rather than individuals as random units has proven to be a more efficient and economical option [38]. In summary, the main aim of this study was to conduct a cluster randomized controlled trial (cluster RCT) to verify the intervention effect of peer education based on adolescence- related knowledge, attitudes, and behaviors on adolescents’ psychological resilience. The main outcomes were at the individual and cluster levels of adolescents. Methods Sample size For superiority trials comparing the means of the two groups, the following formula was used to calculate the sample size [39, 40]: n ¼ ðU1 a þ U1 bÞs d � �2 � 1 þ C C ð1Þ In formula (1), σ is defined as standard deviation; δ is referred to as a clinically meaningful low or high limit that is the width of the 95% confidence interval equally; c is the ratio of sam-

ple cases between intervention group and control group that is equal to 1 in this study. In our research, α and β were 0.05 and 0.10, respectively, so U1-α and U1-β were 1.64 and 1.28, respec- tively. Pre-surveys revealed that σ and δ are 14.85 and 3.14, respectively. Therefore, a sample size of at least 275 was calculated for both groups. DE ¼ 1 þ ðm 1Þr ð2Þ PLOS ONE The effect of peer education based on adolescent health education on resilience of children and adolescents PLOS ONE | https://doi.org/10.1371/journal.pone.0263012 February 2, 2022 3 / 18