1. Department of Paediatrics, Sultan Ahmad Shah Medical Centre, International Islamic University Malaysia, 25200 Kuantan, Pahang, Malaysia
2. Department of Paediatrics, Kulliyyah of Medicine, International Islamic University Malaysia, 25200 Kuantan, Pahang, Malaysia
3. Department of Paediatrics, School of Medical Sciences, University Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
4. Paediatric Clinic, Hospital Sultanah Bahiyah, 05460 Alor Setar, Kedah, Malaysia