BEIJING, Aug. 1 (Xinhua) -- The Chinese government has launched its first large-scale survey on the psychological development of children and teenagers to improve their mental health.

The three-year project would cover over 100,000 children aged six to 15, focusing on their mental development in cognitive ability, study ability and mental health, said China Youth Daily.

The research, initiated by the Ministry of Science and Technology and carried out by State Key Laboratory of Cognitive Neuroscience and Learning in Beijing Normal University, involved more than 80 psychological experts from over 40 colleges.

The project aimed to help standardize the evaluation of mental health and compulsory education quality and to provide basic statistics for scientific research in related fields.

The project was vital for the government in drawing up education policy, said Professor Lin Chongde, of Beijing Normal University and leader of the project.

China had more than 300 million children and teenagers, of whom more than 40 million suffered mental disorders in cognition and study, said Lin.

The report would be completed by the end of 2009.