“…Nine studies were self-administered surveys [17-19, 23, 24, 26-29]eight of these were paper-and-pen and one online [27]. Three studies used face-to-face interviews [21,22,25] and one used autopsy blood samples [20]. Eight studies were conducted in school or college [17-19, 23, 24, 26, 28, 29], two at home [22,25], one each at a youth centre [21], online [27] and at a forensics laboratory [20].…”