Is noteworthy that different age groups were examined, including 23?4 years old in the Australian study [3], 2?7 in the US [24] and 14?8 in the Spanish [23]. In these studies, poly-victimisation was assessed using different methods (telephone get PP58 interviews among the US participants and self-completed questionnairePLOS ONE | DOI:10.1371/journal.pone.0125189 May 1,2 /Poly-Victimisation among Vietnamese Adolescents and Correlatesamong the Australian and the Spanish), and different instruments (the JVQ for both the US and the Spanish samples and study specific questions for the Australian). These differences may affect the comparability of the results. In high income countries poly-victimisation has been shown to have independent detrimental effects on the mental health and adjustment capacity of the victims [21, 25?7] even when controlling for exposure to different single forms of victimisation, including physical assault, property crime, peer or sibling victimisation, child maltreatment, sexual victimisation and witness or indirect victimisation.Poly-victimisation among adolescents in low and middle-income countriesEven though 90 of the world’s adolescents live in low and NVP-QAW039 price middle income countries, evidence about the prevalence and correlates of poly-victimisation among them is scarce and most is journal.pone.0174109 from upper-middle income countries. In a sample of 3,155 12-18-year-old high school students in Shandong province China, 85 of whom resided in a rural area, Dong et al [28] found that two thirds of the students reported at least one form of victimisation in the previous year. Polyvictimisation (which was assessed by the JVQ and was defined in this study as exposure to more than four types) was reported by 17 . In another survey in China using the same instrument, Chan reported similar prevalence estimates of 71 reporting experience of at least one form of victimisation and 14 of poly-victimisation [29]. Compared to the Chinese data, findings from a Malaysian study show a much lower prevalence of 22 of adolescents having experienced at least one form of neglect, physical, emotional or sexual victimisation and 3 experiencing all four [30].However, the use of study-specific questions in this survey compared to a validated measure in the two Chinese studies makes the results from Malaysia and China not directly comparable. Evidence from South Africa suggests higher prevalence of exposure to violence among children and adolescents compared to those reported in other settings. Among 617 South African students aged 12?5 years, Kaminer et al [31] found that 93.1 experienced more than one type of violence and more than 50 experienced four or more types, in the six domains investigated (witnessing of community violence, community victimisation, witnessing of domestic violence, domestic victimisation, sexual abuse and school violence). In these studies [28, 30], poly-victimisation was found to be associated with male gender, younger age, lower socioeconomic status, being an only child, poor parent-child relationship and low quality of school and neighbourhood environment.Poly-victimisation among adolescents in VietnamAlthough there are more than 30 million children and adolescents in Vietnam, and they account for more than a third of the nation’s population [32], there is limited evidence about poly-victimisation among them. Most previous studies in Vietnam only investigated specific forms of victimisation. The UNICEF Multi Indicator Cluster Survey 3, i.Is noteworthy that different age groups were examined, including 23?4 years old in the Australian study [3], 2?7 in the US [24] and 14?8 in the Spanish [23]. In these studies, poly-victimisation was assessed using different methods (telephone interviews among the US participants and self-completed questionnairePLOS ONE | DOI:10.1371/journal.pone.0125189 May 1,2 /Poly-Victimisation among Vietnamese Adolescents and Correlatesamong the Australian and the Spanish), and different instruments (the JVQ for both the US and the Spanish samples and study specific questions for the Australian). These differences may affect the comparability of the results. In high income countries poly-victimisation has been shown to have independent detrimental effects on the mental health and adjustment capacity of the victims [21, 25?7] even when controlling for exposure to different single forms of victimisation, including physical assault, property crime, peer or sibling victimisation, child maltreatment, sexual victimisation and witness or indirect victimisation.Poly-victimisation among adolescents in low and middle-income countriesEven though 90 of the world’s adolescents live in low and middle income countries, evidence about the prevalence and correlates of poly-victimisation among them is scarce and most is journal.pone.0174109 from upper-middle income countries. In a sample of 3,155 12-18-year-old high school students in Shandong province China, 85 of whom resided in a rural area, Dong et al [28] found that two thirds of the students reported at least one form of victimisation in the previous year. Polyvictimisation (which was assessed by the JVQ and was defined in this study as exposure to more than four types) was reported by 17 . In another survey in China using the same instrument, Chan reported similar prevalence estimates of 71 reporting experience of at least one form of victimisation and 14 of poly-victimisation [29]. Compared to the Chinese data, findings from a Malaysian study show a much lower prevalence of 22 of adolescents having experienced at least one form of neglect, physical, emotional or sexual victimisation and 3 experiencing all four [30].However, the use of study-specific questions in this survey compared to a validated measure in the two Chinese studies makes the results from Malaysia and China not directly comparable. Evidence from South Africa suggests higher prevalence of exposure to violence among children and adolescents compared to those reported in other settings. Among 617 South African students aged 12?5 years, Kaminer et al [31] found that 93.1 experienced more than one type of violence and more than 50 experienced four or more types, in the six domains investigated (witnessing of community violence, community victimisation, witnessing of domestic violence, domestic victimisation, sexual abuse and school violence). In these studies [28, 30], poly-victimisation was found to be associated with male gender, younger age, lower socioeconomic status, being an only child, poor parent-child relationship and low quality of school and neighbourhood environment.Poly-victimisation among adolescents in VietnamAlthough there are more than 30 million children and adolescents in Vietnam, and they account for more than a third of the nation’s population [32], there is limited evidence about poly-victimisation among them. Most previous studies in Vietnam only investigated specific forms of victimisation. The UNICEF Multi Indicator Cluster Survey 3, i.
