English: FIGURE 2: Lifetime exposure to violence categories.

Figure 2 describes the co-occurrence of witnessing, victimisation and perpetration previously to the last 12 months. There were 1698 participants in the total sample. Out of those, prior to the last 12 months, 9.14% had solely witnessed violence; 15.29% had been victimised; 5.20% had perpetrated violence. Out of the total sample, 7.17% have experienced victimisation and perpetration; 11.05% reported witnessing violence and victimisation; 3.88% have witnessed and perpetrated violence and 12.19% have experienced all three types of violence. doi:10.1371/journal.pone.0093660.g002 Methods Data from the South East London Community Health Study was used to examine the prevalence, overlap and distribution of proximal witnessed, victimised and perpetrated violence and their association with current mental disorders. We further investigated the cumulative effect of lifetime exposure to violence on current mental disorders. Unadjusted and adjusted (for confounders and violence) models were examined. Results In the last twelve months, 7.4% reported witnessing violence, 6.3% victimisation and 3.2% perpetration of violence. There was a significant overlap across violence types, with some shared correlates across the groups such as being younger and male. Witnessing violence in the past year was associated with current common mental disorders (CMD) and post-traumatic stress disorder (PTSD) symptoms. Proximal perpetration was associated with current CMD, PTSD symptoms and past 12 months drug use; whereas proximal victimisation was associated with lifetime and past 12 months drug use. Lifetime exposure to two or more types of violence was associated with increased risk for all mental health outcomes, suggesting a cumulative effect.

Conclusion

Exposure to violence needs to be examined in a multi-faceted manner: i) as discrete distal and proximal events, which may have distinct patterns of association with mental health and ii) as a concept with different but overlapping dimensions, thus also accounting for possible cumulative effects.