2.4. Self-Harm History

Self-harm history was established via items adapted from the Adult Psychiatric Morbidity Survey (APMS; [11]) to assess lifetime prevalence of NSSI and suicide attempts. These behaviours were assessed by the following items: “Have you ever harmed yourself without wanting to die, by taking an overdose of tablets or in some other way?” and “Have you made an attempt to take your life, by taking an overdose of tablets or in some other way?”. Self-harm history includes endorsements of either or both of these behavioural items. Participants were also asked to indicate how many times in their life they had engaged in these behaviours.