Examining medication safety in mental health hospitals

  • Ghadah Alshehri

Student thesis: Phd


Medicines are the most frequently used clinical interventions to treat mental health illnesses. Patients with mental health illnesses have a set of potential risks that make them more likely to experience medication safety problems including medications errors (MEs) and adverse drug events (ADEs). Such risks are related to the type of medications used, nature of their illnesses as well as the settings where treatment takes place. This clearly highlights the need for investigating the safety of medicines use in mental health hospital settings. This is in line with international patient safety policy initiatives, including the recent National Health Service (NHS) Patient Safety Strategy that recommended the development of theory-driven and evidence-based remedial interventions to improve patient safety in health care systems. Therefore, the programme of work presented in this thesis focused on understanding the frequency, nature and contributory factors of MEs and ADEs in mental health hospitals in order to generate informed recommendations that can bring about improvements in medication safety for this vulnerable patient group. Evidence from 20 studies concerning the rate and nature of MEs and ADEs in mental health hospitals was evaluated in a systematic review. The rate of MEs ranged from 10.6 to 17.5 per 1000 patient-days (n=2 studies) and ADEs from 10.0-42.0 per 1000 patient-days (n=2), with 13.0 -17.3% of ADEs found to be preventable. Prescribing errors occurred in 4.5-6.3% of newly written or omitted prescription items (n=3); medication administration errors occurred in 3.3-48.0% of opportunities for error (n=5). A subsequent observational study addressed the lack of evidence concerning the burden of ADEs in the NHS by investigating the rate, nature and risk factors of ADEs occurring in three mental health trusts. A total of 227 patient admissions involving 10,164 inpatient days were included, with ADEs observed in 12.6% [95% CI 5.6 to 26.0] of admissions with a rate of 2.6 [95% CI 1.0-6.9] per 1000 patient-days. Nineteen percent of the total ADEs reported were found to be preventable (n=9/47). The ‘central nervous system’ medication class was the most commonly involved, including antipsychotics and antidepressants. Patients with a longer hospital stay were found to be significantly more likely to experience an ADE compared to patients with a stay of up to 7 days. A mixed method evaluation of medication incidents reported to the National Reporting and Learning System (NRLS) in England and Wales during 2010-2017 was then conducted in order to examine in-depth their nature and reported contributory factors to highlight targets for future improvement. A descriptive analysis of 94,134 medication incidents showed that the majority of the medication incidents originated from the administration and prescribing stages with the antipsychotic medication class being the most frequently reported. This was followed by a thematic analysis of 1,070 free-text reports associated with at least moderate patient harm which identified failure to follow protocols (n=93), lack of continuity of care (n=92), patient behaviours (n=62) and lack of stock (n=51) as the most frequently reported contributory factors associated with medication incidents. This thesis has found that MEs and ADEs are common and have serious consequences for patients in mental health hospitals. Whilst a number of improvement recommendations for current policy and practice have been identified based on the findings generated from this thesis, it also identified an action agenda for future research including understanding medication safety at transition points of care, targeting high risk patient groups such as elderly patients and testing the effectiveness of interventions designed to reduce their occurrence in hospitals.
Date of Award1 Aug 2020
Original languageEnglish
Awarding Institution
  • The University of Manchester
SupervisorDarren Ashcroft (Supervisor) & Richard Keers (Supervisor)


  • medication errors
  • Medication safety
  • mental health hospitals
  • adverse drug events.

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