Corporal Punishment Bans, Childhood Adversity, and Adolescent Suicide Rates: An International Ecological Study
Suicide , Adolescent health , Mental health , Childhood adversity , Socioeconomic status , Corporal punishment , Epidemiology , Population-level study
Corporal punishment is associated with poor mental health outcomes, including suicidal behaviour, in adolescents. At a population level, legislation banning corporal punishment is associated with many health outcomes in children. Therefore, the overarching objective of this thesis is to investigate the relationship between legislation banning corporal punishment and adolescent suicide rates across countries and cultures, both cross-sectionally and using time series methods. Sources of childhood adversity were explored as potential effect modifiers. This thesis used exclusively population level secondary data. Negative binomial models were constructed to investigate the cross-sectional objectives. Negative binomial mixed models were used to investigate the time series objectives. Compared to the 39 countries that had enacted a full ban (in homes, schools, daycares, and alternative care settings) of corporal punishment, the 19 countries that had not banned corporal punishment reported 2.07-fold the rate of suicide in females aged 15-19 (RR 2.07, 95% CI 1.07-4.01). Twenty countries that permitted corporal punishment in schools also reported a higher rate of suicide in female adolescents aged 15-19 (2.01-fold the rate of 77 countries that had banned school corporal punishment). There was evidence of lagged effects of partial bans of corporal punishment and bans of corporal punishment in schools; these effects peaked after 12 years for females aged 15-19 and after 13 years for males aged 15-19. There was no evidence of effect modification by the socio-economic (SES) Index. There was also no statistically significant evidence of effect modification by the Childhood Adversity (CHA) Index, but the interaction term for females aged 10-14 between partial bans of corporal punishment (bans enacted in some, but not all, of the four settings investigated) and the CHA Index approached statistical significance (RR 0.60, 95% CI 0.36-1.00, p-value 0.0502). The beneficial effects of banning corporal punishment in all settings may be reduced in countries with greater levels of childhood adversity. The results of this study add to a body of evidence that suggests that legislation banning corporal punishment may promote adolescent health and well-being. In combination with future research, these findings may be applied to reduce adolescent suicide rates at a national level.