[1] Univ Malaya, Dept Pediat, Fac Med, Kuala Lumpur 50603, Malaysia
[2] Minist Hlth, Inst Med Res, Endocrine & Metab Unit, Kuala Lumpur, Malaysia
[3] Putrajaya Hosp, Dept Pediat, Putrajaya 62250, Malaysia
[4] Univ Malaya, Fac Med, Dept Social & Prevent Med, Kuala Lumpur 50603, Malaysia
[5] Univ Malaya, Fac Med, Dept Sports Med, Kuala Lumpur 50603, Selangor, Malaysia