Acknowledgements: This material is based upon the TNCs supported by the Human Resource for Health Research and Development Office, Health System Research Institute, the International Health Planning and Policy, and the Thailand Nursing and Midwifery Council. All contents of this material, including opinions, findings, discussion and conclusions or recommendations, are those of the authors and do not necessarily reflect the official view of the TNCs Steering Committee. The authors thank to all cohort members for their valuable participations.