1 Department of Community Health, Faculty of Medicine, UKM Medical Centre, Universiti Kebangsaan Malaysia, Kuala Lumpur, Cheras, Malaysia.
2 Department of Community Health, Faculty of Medicine, UKM Medical Centre, Universiti Kebangsaan Malaysia, Kuala Lumpur, Cheras, Malaysia. ramalbaru@gmail.com.
3 Faculty of Medicine, Universiti Teknologi MARA Sungai Buloh, Sungai Buloh, Selangor, Malaysia.
4 Department of Diagnostic & Allied Health Science, Faculty of Health and Life Sciences, Management & Science University, Shah Alam, Selangor, Malaysia.