“…3,5,9,16,18 The comparability of these cross-sectional studies is however limited since the level of knowledge was assessed using different methods: by interview; 7,14 drawing techniques; 13 or structured questionnaire. 3,5,6,[8][9][10]12,15,16,[18][19][20][21] However, in several studies that used questionnaires, these had limited or no data that supported the validity or reliability of the questionnaires. [8][9][10]12,15,16,18 To enhance the level of knowledge in patients, repetitive and structured educational interventions are recommended.…”