Section 3. Aims and methodology Section 3. Aims and methodology 3.1 This inspection examined the separation of children in prisons in England and Wales. The key aims of the review were to:    3.2 further investigate treatment and conditions in segregation units, including the number of children segregated, for how long and if they are reintegrated effectively better understand the experiences of children who are separated (both in segregation units and on other units they might be separated) make recommendations on the treatment and conditions of children who are separated. In acknowledgment of the fact that children can be separated in many locations within a YOI, the following areas or locations were included in this inspection:     designated segregation units other separation units, such as the Bridge unit at Cookham Wood and the enhanced support unit (ESU) at Feltham A segregation on normal location segregation conditions in other areas (such as health care). Methodology 3.3 This report draws on in-depth inspections in spring 2019 focusing on the separation of children in all five YOIs that hold children in England and Wales. Additional analysis of HMI Prisons survey data was conducted to give a national picture. HMI Prisons survey data analysis 3.4 We analysed HMI Prisons survey data for children in YOIs for the 2018–19 annual reporting year. These surveys were undertaken as part of our planned inspection programme, during which all children in YOIs were offered a questionnaire to complete. We also carried out an analysis of all children who were separated at the time of the survey, either in a designated segregation unit or specific separation unit (Bridge unit at Cookham Wood and the ESU at Feltham A). It was not possible to include children who were separated on normal location in this analysis. Primary data collection 3.5 In May and June 2019, we carried out primary fieldwork in all five YOIs that hold children in England and Wales:      3.6 HMYOI Cookham Wood HMYOI Feltham A HMYOI Parc HMYOI Werrington HMYOI Wetherby and Keppel The fieldwork included the following activities:   individual interviews with children who had experienced separation in the establishment individual interviews with operational and professional staff involved in the supervision and care of separated children Separation of children in young offender institutions 19