Funding for this research was provided by:
Ministry of Education (Singapore) AcRF Tier 2 Grant (MOE2012-T2-1-079)
Text and Data Mining valid from 2019-01-05
First Online: 5 January 2019
Compliance with Ethical Standards
: The authors declare that they have no conflict of interest.
: This study was approved by the Institutional Review Board at Nanyang Technological University. The Ministry of Education of Singapore and the school principals also approved the data collection at the schools.
: Informed consent was obtained from all individual participants included in the study.