[How many TBS patients give informed consent for retrospective file research?]

In practice, it is assumed that because of the psychopathology and the coercive context, obtaining informed consent from forensic psychiatric patients for retrospective file research, without direct reward, is difficult and could result in selection bias. However, this has not been studied before.

To explore the willingness of forensic psychiatric patients to give informed consent for retrospective file research.

A explorative pilot study in which patients from the resocialization units of FPC Mesdag were informed by the clinician responsible for their care about a retrospective file study into the position of trauma treatment in the treatment process. It was registered how many patients could have been informed, how many were informed, how many agreed to be approached by a researcher and how many gave informed consent.

Of the 96 patients, 74% (n = 71) were informed. 32% (n = 23) agreed to be approached by a researcher. 31% (n = 22) gave informed consent.

The willingness of forensic psychiatric patients appears to be limited. The fact that a small group from a presumably very heterogeneous population gives informed consent provides a strong indication that asking for informed consent in retrospective file research could lead to selection bias. Also, the group that gives informed consent turns out to be too small to conduct thorough research.