Introduction

Child sexual abuse (CSA) is one of 24 global risk factors identified by the World Health Organization (Mathers et al, 2009) that substantively affect the global burden of disease, since it increases the risk of a range of difficulties in adult life, including depression, anxiety disorders, drug or alcohol abuse, and suicide. Due to the secrecy and taboo around CSA and low rates of disclosure it is difficult to assess the extent of CSA; and incidence varies between countries, with estimates ranging from around 4% of men in high-income countries to more than 40% of women in parts of Africa and Asia. Around a third of post-traumatic stress disorder cases in women and a fifth in men are attributable to CSA (Andrews et al, 2004), as are between 5% and 8% of alcohol and drug use disorders. Mathers and colleagues (2009) estimated that CSA contributed an estimated 0.6% to the global burden of disease, or 9 million years of healthy life lost. The effective prevention of CSA could therefore have a significant impact globally. In order to do this, however, we need to know what factors cause or increase the risk of CSA, as explained by Walklate in the opening chapter of this book. The purpose of this chapter, therefore, is to provide an overview of what the research evidence tells us about risk and vulnerability in relation to both the victimisation and perpetration of CSA.

There is variability across the world in definitions of CSA, which makes it difficult to compare findings across studies, and for practitioners to have a shared understanding, or a single set of evidencebased policies and strategies. Definitions vary within close regional areas, and there are different practice frameworks and policies between organisations, and regions. This makes it difficult for practitioners working across boundaries/regions, challenging for multi-agency working, and for communication in respect of individuals who have criminal or victimisation histories that cross geographical and practice boundaries. In the UK, child sexual exploitation (CSE) is regarded as a form of CSA. Here there are different definitions of CSE in each of its countries, as well as some important practice-relevant definitions, such as high and low risk, which varies by local authority, regions and organisations, and sub-areas/regions of these (Brown et al, 2017).