comparison of the effect of motivational interview and peer group education on knowledge and performance about puberty and mental health in adolescent girls

Context: adolescence is one of the most important periods of a person’s life due to physical, mental andsocial maturity. aim: the aim of this study was to compare the motivational interview and peer groups in promoting mentalhealth and knowledge and performance about puberty health in adolescent girls. setting and design: this is a semi‑experimental intervention study with two intervention groups and one control group. the study was conducted at the high schools during the academic year of 2018–2019 in shahroud, iran. materials and methods: in this study, 334 female students (13–15 years old) were allocated to three groupsby assigning the schools to two intervention and one control groups through simple randomization. in intervention group 1, five motivational interview sessions were held and in intervention group 2, training was conducted by peers. the tools used in this study was a researcher‑made questionnaire designed to assess knowledge and performance about puberty health and symptom checklist‑25 to measure mental health. statistical analysis used: in this study, data were analyzed using descriptive statistics and analytical statisticaltests include anova, repeated measure, pearson correlation, chi‑square. results: immediately after, and 1 month after the intervention, the two intervention groups had significantly better scores in knowledge, performance, and mental health compared to the control group. the scores were better in the peer group compared to the motivational interview group for all threevariables. conclusions: both motivational interview and peer group were effective in increasing knowledge and performance in adolescent girls.