“…1). Four studies were designed as prospective cohort studies [15,23,28,31], and rest were case series [12-14,16-22,24-27,29,30,32,33]. Three studies by Metcalfe et al [16,17,19], two studies by Brandberg et al [23,28], two studies by Gahm et al [21,25] and another three studies by Gahm et al [26,27,32] were each based on same patient populations.…”