Sheri Madigan and colleagues'1 systematic review evaluates whether the COVID-19 pandemic has affected paediatric emergency department visits for attempted suicide, self-harm, and suicidal ideation. They report that the combined rate of emergency department visits for attempted suicide and suicidal ideation increased among girls (rate ratio 1·39, 90% CI 1·04–1·88), whereas there was no significant change among boys (1·06, 0·92–1·24).1 We were interested in this difference between the sexes because the COVID-19 pandemic appears to have had a greater impact on the behaviour of girls than boys in Japan. Therefore, we decided to analyse cases of death by suicide among adolescents and young adults in Japan.