Background: Special observation (the allocation of nurses to watch over nominated patients) is one means by which psychiatric services endeavour to keep in-patients safe from harm. The practice is both contentious and of unknown efficacy.
Aims: To assess the relationship between special observation and self-harm rates, by ward, while controlling for potential confounding variables.
Method: A multivariate cross-sectional study collecting data on self-harm, special observation, other conflict and containment, physical environment, patient and staff factors for a 6-month period on 136 acute-admission psychiatric wards.
Results: Constant special observation was not associated with self-harm rates, but intermittent observation was associated with reduced self-harm, as were levels of qualified nursing staff and more intense programmes of patient activities.
Conclusions: Certain features of nursing deployment and activity may serve to protect patients. The efficacy of constant special observation remains open to question.