A comparison of the clinical effectiveness and costs of mental health nurse supplementary prescribing and independent medical prescribing: a post-test control group study

BACKGROUND Supplementary prescribing for mental health nurses was first introduced in the UK in 2003. Since then, a number of studies have reported stakeholders' perceptions of the success of the initiative. However, there has been little experimental research conducted into its effectiveness. This paper reports findings from the first known study to compare the cost and clinical impact of mental health nurse supplementary prescribing to independent medical prescribing. METHODS A post-test control group experimental design was used to compare the treatment costs, clinical outcomes and satisfaction of patients in receipt of mental health nurse supplementary prescribing with a matched group of patients in receipt of independent prescribing from consultant psychiatrists. The sample comprised 45 patients in receipt of mental health nurse supplementary prescribing for a minimum of six months and a matched group (by age, gender, diagnosis, and chronicity) of patients prescribed for by psychiatrists. RESULTS There were no significant differences between patients in the nurse supplementary prescribers' group and the independent prescribers' group in terms of medication adherence, health status, side effects, and satisfaction with overall care. Total costs per patient for service use were 803 pounds higher for the nurse prescribers' group but this difference was not significant (95% confidence interval--1341 pounds to 3020 pounds). CONCLUSIONS No significant differences were found between the health and social outcomes of patients in the mental health nurse supplementary prescribers' group, and those prescribed for by the independent medical prescribers. The cost appraisal also showed that there was no significant difference in the costs of the two types of prescribing, although the pattern of resources used differed between patients in the two prescriber groups. The results suggest that mental health nurse supplementary prescribers can deliver similar health benefits to patients as consultant psychiatrists without any significant difference in patients' service utilisation costs.