[1] Univ Sains Malaysia, Sch Med Sci, Unit Biostat & Res Methodol, Kubang Kerian 16150, Kelantan, Malaysia
[2] Univ Sains Malaysia, Sch Med Sci, Dept Community Med, Kubang Kerian 16150, Kelantan, Malaysia
[3] Univ Sains Malaysia, Sch Med Sci, Dept Pediat, Kubang Kerian 16150, Kelantan, Malaysia
[4] Univ Sains Malaysia, Sch Dent Sci, Kubang Kerian 16150, Kelantan, Malaysia
[5] Univ Sains Malaysia, Sch Hlth Sci, Kubang Kerian 16150, Kelantan, Malaysia