from Health Economics at https://bit.ly/3eJigtF on November 9, 2020 at 11:14PM
Adolescent mental health is key for later well-being. Yet, causal evidence on environmental drivers of adolescent mental health is scant. We study how an important classroom feature—the gender composition in compulsory-school—affects mental health. We use Swedish administrative data (N=576,285) to link variation in gender composition across classrooms within cohorts to mental health. We find that a higher share of female peers in a classroom increases the incidence of mental health diagnoses, particularly among boys. The effect persists into adulthood. Peer composition is thus an important and persistent driver of mental health.