Question: In patients that self-harm and present at emergency departments, how effective are follow-up postcards, compared to treatment as usual, in improving patient outcomes (e.g. a decrease in re-presenting to emergency departments, decrease in self-harming behaviour, reduction in time spent in hospital).

Answer:

The evidence came from three RCTs and one systematic review (containing an additional two trials) of postcard interventions, only two of the RCTs were at low risk of bias. There was one trial in adults who deliberately self-harmed and presented at an appropriate emergency department (toxicology as it was a trial of self-poisoning). This found reductions in both the number of hospital admissions for repeat self-poisoning attempts and the number of days spent in hospital. The other trials found reductions in repeat presentations for self-harm (one trial), and reductions in suicide attempts (two trials). One trial did not find any significant differences between postcards and treatment as usual, this was the smallest study.

More research is needed in this population as not all the current research is in adults presenting at emergency departments, most studies were in people being discharged from other units, such as toxicology or psychiatric units. Not all the trials measured the specified outcomes, especially time spent in hospital. This was only reported by one trial. None of the research was conducted in the UK so these results may not be generalisable. Further high quality RCTs are needed which measure relevant patient and service use outcomes and also measure compliance with the intervention, as not all participants will take notice of the postcards.