Exploring children's knowledge of COVID-19 and stress levels associated with the pandemic in Nigeria: a mixed-method study - Shanti Raman; Sharanya Napier-Raman; Osamagbe Aiyudubie Asemota; Hajime Takeuchi; Enosakhare Aiyudubie Asemota; Ezeh Nonye (BMJ Publishing Group, 2022)