1.2 billion ทั่วโลก มีอายุ 10-19 ปี หรือประมาณ 1 ใน 6 ของประชากรโลก เป็นวัยเรียนตอนปลายและวัยรุ่น (http://www.who.int/mediacentre/factsheets/fs345/en/)
The health of adolescents has improved far less than that of younger children over the past 50 years.
The present generation of young people will take a different path through adolescence from previous generations and will face new challenges to their health and wellbeing. How they negotiate these years will have a powerful effect on their future health and their countries’ economic and social prospects.
Neurocognitive development is another element of biological maturation with major effects on decision making, emotional wellbeing, and behaviour.
A life-course perspective emphasises that the health of adolescents is affected by early childhood development and the biological and social-role changes that accompany puberty, shaped by social determinants of health that affect the uptake of health-related behaviours. The onset of these behaviours and states in adolescence affect the burden of disease in adults and the health and development of their children.