[1] Univ Leicester, Leicester Gen Hosp, Sect Adult Social & Epidemiol Psychiat, Dept Hlth Sci, Leicester LE5 4PW, Leics, England
[2] Leicester Royal Infirm, Div Womens & Childrens CMG, Leicester, Leics, England
[3] Univ Nottingham, Queens Med Ctr, Sch Hlth Sci, Nottingham NG7 2RD, England
[4] Univ Liverpool, Inst Psychol Hlth & Soc, Clin Psychol, Liverpool L69 3BX, Merseyside, England