A screening tool used for detecting suicide risk in general hospital patients who have self-harmed is ineffective and should no longer be used, new research suggests.
The SADPERSONS scale does not identify the majority of those who need to be admitted to a psychiatric unit, according to the study published online in Emergency Medicine Journal.
It also fails to detect most cases where community psychiatric aftercare is required or where further self-harm is likely, the researchers said.
Current national guidance in England states a full psychosocial assessment should be carried out with all patients who attend hospital after an episode of self-harm.
However, the study found that pressures due to waiting time targets and declining availability of mental health services mean that this does not always happen in practice.
It reported that emergency care staff are increasingly inclined to use rating scales to determine which patients may be discharged from hospital without a full assessment.
The SADPERSONS Scale, developed in the US in 1983, is based on 10 risk factors. The authors of the study suggest it has changed little since it was first invented.
For the study, they assessed SADPERSONS scores given to 126 patients consecutively admitted to an emergency medicine department in a major general hospital in Oxford during the summer of 2011.
Their aim was to assess the accuracy of the SADPERSONS score in terms of how well it predicted the future care and treatment given to individual patients.
They reported that admission to a psychiatric unit was required in five cases (4%), while community psychiatric aftercare was needed in just over half (55%; 70).
Around one in four patients (24.6%) self harmed again on at least one occasion.
The study found that the SADPERSONS Scale picked up just 2% of those needing admission to a psychiatric unit, around 6% of those needing community psychiatric aftercare and just over 6.5% of those likely to self harm again.
The authors by stressing that it is vital that any tool designed to identify suicide risk is highly accurate and has a low rate of false negative results so that those at risk of committing suicide do not go undetected.
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