Drug Administration Errors

Introduction

In this chapter, we will define what drug administration errors are, and discuss the contributing factors which can increase the likelihood of them occurring. We will explore the actions that should be taken by nurses in the context of both UK law and the Nursing and Midwifery Council (NMC) guidelines if a drug administration error is identified. We will also discuss the ways in which drug administration errors can be prevented. Finally, the application of these concepts to everyday nursing practice will be illustrated using a detailed hands-on scenario.

What is a drug administration error?

In order to reduce the risk of drug administration errors occurring it is essential that we understand how these errors can occur, and the factors which can make their occurrence more likely. A drug administration error is where an incorrect or inappropriate administration of a drug to a patient occurs in comparison with either the prescription or local hospital policy. This could include the wrong drug being administered, or at the wrong strength or dosage, or to the wrong patient. The consequences of these errors can range from insignificant effects to patients through to patient death. It is therefore of great importance that all medical staff including nurses work together with institution policy makers to reduce the risks posed to patients by medication errors. Drug administration errors are thought to be common, with some observational research studies suggesting that between 19% and 27% of all drug administration errors had some degree of error (Westbrook et al., 2010; Colen et al., 2003; Ghaleb et al., 2010). It is thought that the risk of error with intravenous drug administration is particularly high, with one UK based study indicating that almost 70% of IV drug administrations included some degree of clinical error. Furthermore, the chance of an IV drug administration resulting in serious adverse effects to the patient is higher than administration by other groups, with one UK study identifying 1% of IV drug administrations as causing severe adverse effects and 29% causing moderate effects (Taxis and Barber, 2003, p.1).

Drug administration errors can result from the effects of active failures in medical practice or latent conditions within the organization. Active failures might include a lapse in concentration causing a nurse preparing a drug for administration to select the wrong dosage of drug, or a lack of knowledge resulting in a drug being administered by the wrong route. Latent conditions tend to refer more to inbuilt factors within local policy and practice that can result in inevitable errors occurring. For example, understaffing may result in nurses having inadequate time or provision to concentrate on drug preparation, or a poor medical equipment maintenance schedule could result in a drug administration error from malfunctioning equipment.

Common Causes of Drug Administration Errors

Individual Causes

One common cause of drug administration errors is an error in preparing and administering the prescribed drug - for example, not correctly following the prescription instructions or the local protocols associated with the use of a particular drug. A common cause of errors is tiredness; long shifts or repeated night shift working can cause all healthcare professionals to make errors in judgement or by omission. However, it should be considered that tiredness can be the effect of institutional factors such as short staffing, or procedural failure to address a lack of staff due to sickness absence. A loss of concentration resulting from tiredness or distraction on the ward could result in the nurse omitting a dose of a scheduled medication or even administering an incorrect drug or drug dosage. Working in an unfamiliar environment with unfamiliar policies and procedures can also provide the opportunity for a nurse to make an error. For example, although regular staff on a ward may be used to poor organisation of IV fluid bags and may account for this in their practice by double checking they have selected the right one, a nurse unfamiliar with that environment might not realise that there was a risk of the wrong fluid being selected due to poor labelling. Knowledge-based errors can also occur as a result of a lack of knowledge and understanding on the part of the nurse regarding a drug's action, usual route of administration or mechanism. This could either result in an error being made by the nurse themselves (e.g. administration via an incorrect route) or prevent the nurse from identifying a prescribing error.

Communication problems are also a common cause of medical and drug administration errors. For example, instructions may be poorly recorded, with unclear handwriting, or contain unfamiliar or ambiguous abbreviations rather than full drug names and dosages. Units for drug dosage can also be unclear, or the incorrect unit used. Addressing these issues can sometimes be difficult for nurses, as historically the imbalance of power between doctors and nurses can cause doctors to become defensive when questioned, or nurses to feel that it would be inappropriate to question the doctor; however, modern teaching for both doctors and nurses aims to break down these barriers and encourage communication between professionals of all disciplines. Nurses can also employ conflict management techniques such as assertiveness into their communications if appropriate. However, ultimately, nurses do have a duty to question any instructions that are unclear, or that they believe may be incorrect, as this is a valuable way of identifying prescribing errors at an early stage before the wrong drug or dosage of drug is given to the patient. It is also possible to make errors when calculating the dosage of a drug; for example, if the instruction stipulates a particular dosage per kg of patient body weight, the nurse may need to determine what the total dosage should be for that specific patient. Finally, prescribing errors can also occur if a drug was prescribed without adequate consideration of allergies or potential drug interactions. Although these would be considered to originate from the prescriber rather than the nurse administering the drug, the nurse still has a responsibility to consider the appropriateness and accuracy of the prescribing decision in the context of their own knowledge and experience. This might mean systematically asking every patient about their medication history or any known allergies before each drug administration (for example, as part of the "5 rights" or "9 rights" rule), or questioning a prescribing decision that appears unusual, or that may be inappropriate when all aspects of the patient's treatment plan are considered.

Institutional Causes

Institutional causes of medical and drug administration errors can include a failure of local protocols to support safety interventions such as the "5 rights" or "9 rights" rules. They can also include failures in management, such as inadequate provision of staff or resources for a department, or an unclear or ineffective management structure.

An important safety consideration is that of the culture fostered within the institution with regards to patient safety. In 2013, the Francis Report published the results of an investigation into systematic failures in patient care and safety at the Mid Staffordshire NHS Foundation Trust, which ultimately resulted in multiple preventable patient deaths. Although the investigation identified that the unsafe practice of a small number of midwives contributed to these deaths, the investigation also illustrated the impact that an unsafe working culture can have on patient safety. In this case, several midwives at this hospital perpetuated a culture that had little consideration of patient safety and the potential for errors to occur, which also facilitated the covering of clinical errors and a lack of transparency in reporting to both the supervisor of midwives and to members of the multidisciplinary team. This resulted in unsafe practice continuing for several years before it was finally identified.

As a result, it has been identified that increasing care transparency and reducing the fear associated with the reporting of drug administration errors and other care failures is vital in reducing medical errors. Therefore, the NMC advocates that institutions work towards establishing a working culture where errors, near misses and safety concerns can be reported and discussed in an open and supportive manner. The aim of this is to encourage more nurses to come forward by reducing the fear of disciplinary action, and therefore to identify potential safety risks at an early stage. Furthermore, an open and frank discussion of the factors contributing to a medical error can help institution managers to identify any common themes or organisational and policy issues that may be compromising patient safety, so that they may take steps at an early stage to prevent errors. A safe working culture can therefore be described as one that has core safety values common to all staff, such as shared beliefs and ethically acceptable norms. This can help nurses to more easily identify practice that does not fit these core values, and support the reporting of their concerns. Furthermore, when an individual is surrounded by other individuals conforming to a certain set of values and beliefs, they are more likely to adopt the same set of values and beliefs themselves. In this way, nurses can encourage safe practice in others by working in a safe manner themselves.

Nurses should also consider the potential for organisational and individual factors to overlap. This can be illustrated by the Swiss Cheese Model, published in 2000 by James Reason. The model describes how patient safety errors can occur when multiple complementary organisational errors occur simultaneously. The model considers safeguarding interventions to be like slices of swiss cheese, or as generally solid but with occasional holes (in this context, a failure in safeguarding procedure as a result of latent conditions or an active safety failure). If lined up together, the solid areas of safeguarding interventions should overlap the holes in other layers, so that the hole is not present throughout the slices. However, if multiple holes, or failures in safeguarding processes, occurred simultaneously or at complementary times, this could result in the hole being apparent through all the layers, indicating the possibility of the failures to break through all the current safeguarding barriers and result in a patient safety event.

Responsibilities of Nurses

All patients have the right to receive high quality and safe healthcare under the NHS Constitution. Healthcare under the NHS is therefore regulated by policy at all levels to guide healthcare practice in a manner that is safe and conducive to quality care. This is independently regulated by the Care Quality Commission (CQC). The NMC Code stipulates that registered nurses are accountable for their decisions and practice, as well as being accountable for the practice of any competent individuals they have delegated a task to (e.g. a student nurse acting under their direct supervision) (NMC, 2015b). Nurses are legally and ethically accountable for the quality and safety of the patient care they provide to both their professional regulatory bodies (such as the NMC), and to their employer (such as their local hospital trust). Additionally, nurses have a responsibility to report unsafe practice or issues with care quality (Hood, 2013). This responsibility is recognised by the CQC, who consider that nurses are ideally placed within the multidisciplinary team to identify the unsafe practice of others, or institutional or policy issues that may have an adverse effect on patient safety. The reporting of these issues is known as "whistle blowing", and following high profile safety issues such as those outlined in the Francis Report, it has been identified that nurses should receive professional and legal protection against any negative ramifications of the reporting of patient safety concerns.

It has been suggested that nurses commonly receive disproportionate blame for medication errors, regardless of the cause and the level of involvement of other multidisciplinary team members in the situation (Wright, 2013). For example, some authors have reported a tendency for investigations to make assumptions regarding the skill and ability of nurses to perform drug calculations (Harvey et al., 2010; Ramjan, 2011).

Methods of Preventing Errors

It has been suggested that the risk of human error can be reduced by considering the causative factors as part of a person-centred approach or a systems approach. Person-centred human errors (for example, when a nurse performs an unsafe act) can be reduced by targeting the known causative factors, such as poor motivation, inattention, negligence or forgetfulness. The risk of these could be reduced by retraining staff on a regular basis, or using posters to advise staff on best practice or potential disciplinary procedure. However, a systems approach would be more effective in combatting organisational issues, such as changing the layout of drug charts if an error investigation identifies that some staff experience confusion when completing these. Systems-based approaches therefore focus more on identifying why organisational safeguarding procedures failed, rather than focusing on the individual who committed the error.

As previously discussed, systematic frameworks such as the "5 rights" rule and the "9 rights" rule can be of great use in reducing drug administration errors by guiding the nurse to consider multiple aspects of the drug administration process in the context of identifying common causes of errors. The nurse can also utilise the patient in reducing the risk of errors - for example, by asking the patient questions such as "when did you have your last dose?" to check that the time of the previous dose was recorded correctly.

Another approach to reducing future drug administration errors is to review the current policy in relation to the direct influences behind the original error. For example, if an investigation identified that a drug administration error had occurred as a direct result of the nurse being distracted by a patient or colleague, the ward manager could consider introducing an approach such as protected medication time. Interruptions have previously been identified as a common cause of incorrect medication administrations (Ford, 2012). Under this protocol, the nurse undertaking the drugs round is clearly indicated, for example by wearing a coloured tabard with a "Do not disturb" sign on. Staff, patients and visitors can be made aware of the importance of not distracting the nurse performing the drugs round, for example by displaying educational posters around the ward setting. This approach has been successfully implemented by several NHS trusts, including Wrighton, Wigan and Leigh NHS Foundation Trust, The Christie hospital, and Cardiff and Vale NHS Trust between 2011 and 2013. These trusts reported a moderate reduction in the incidence of interruptions, although the overall effect on error incidences is uncertain. However, there is some controversy surrounding this approach, as it has been criticised by some patient groups as making patients feel that they cannot ask for help if needed (Beckford, 2011).

However, there are also novel ways in which errors can be prevented that are specific to the underlying cause. For example, the risk of errors occurring as a result of the nurse selecting the wrong drug could be reduced by using automated dispensing cabinets. These often use a barcode-based system and can restrict access to only the drawer or compartment containing the drug that should be dispensed (Cottney, 2014). Researchers with an interest in reducing drug administration errors have also suggested that errors caused by incorrect drug dosage calculations could be reduced by promoting the use of specially designed smartphone-based applications that can help nurses to perform these calculations, or rapidly access drug safety information (Segal et al., 2015).

Error Reporting and Investigative Process

In the event that a nurse identifies a drug administration error, the first consideration should always be patient safety. The nurse should immediately take any action necessary to ensure that the patient is not harmed by the error, and that any harm is rectified as quickly as possible. For example, in the event of a drug overdose, the nurse should ensure that the patient receives frequent monitoring and any necessary drugs indicated to reverse the effects of the overdose. The error should also be documented immediately in the patient's notes and any necessary paperwork indicated by local policy should also be completed. The procedure for error reporting may vary between institutions due to local policy, which is usually created in accordance with NMC guidance, and a nurse should always follow this in the first instance. The NMC guidance stipulates that the nurse should immediately notify the prescribing practitioner, their line manager and their employer (although this may vary in accordance with local guidance).

Nurses have a professional duty of candour to be honest with their patients, colleagues and management. They should therefore be open with patients (or their next of kin if appropriate) about any medical or drug administration errors. Patients should be informed about the error, and offered any support needed to deal with any short or long term effects of the error. Patients should also receive an apology, and be assured that the correct procedure will be followed and the situation learned from to improve future patient care.

The NMC requires that drug administration errors be investigated in a full and transparent manner, in order that all contributing factors are identified so that they may be addressed and the chance of future errors reduced. The NMC also recommends sensitive management of error investigation, as it recognises that error reporting is more likely occur and attempts to cover errors are reduced when nurses do not fear that the investigative process will automatically result in them being blamed or being disciplined without due cause. The NHS culture has been criticised as having a tendency to apportion blame to individuals without taking the specific circumstances of the event into due consideration, and reports published by the CQC have identified that this can hinder the ability of the NHS and healthcare professionals to learn from safety events in order that reoccurrence might be prevented. Additionally, the NMC recognises the difference in management required for errors that have resulted from external pressures (e.g. understaffing), and those that have resulted from reckless or careless behaviour - particularly when there is evidence that individuals have attempted to conceal their involvement in an error or have hesitated to report it. Therefore, the NMC encourages local management to also consider this difference when undertaking local disciplinary action.

In England and Wales, medical and drug administration errors should also be reported to the National Patient Safety Agency (NPSA) via the National Reporting and Learning System (NRLS) so that the circumstances of the error can be considered at a national level and that any lessons that can be learnt from the error (e.g. the need for a policy change) can be implemented nationwide so that all patients in all areas can benefit from improved safety. Drug administration errors should also be reported to the CQC, who may wish to conduct an independent investigation, or to make their own recommendations to reduce the risk of the error occurring again.

It should also be considered that a drug administration or medical error is likely to have a significant impact on a nurse's confidence, which may increase the likelihood of other future errors occurring, or for the nurse to consider leaving the profession. It is therefore important that as well as ensuring the nurse receives any additional training indicated as necessary by the investigative process, the nurse also receives support from their line manager and employer to view the experience as a learning issue that can be prevented by improving future practice.

Conclusion

Drug administration errors are common, despite research identifying common causes at both an individual and organisational level. By being aware of the common causes of errors and the strategies that can be incorporated into everyday practice to reduce the frequency of errors (such as the "5 rights" or "9 rights" rule, or protected medication rounds), nurses can improve the safety of the care they offer their patients. Nurses and other healthcare professionals should be aware of the advantages of correct error reporting, and how this can be used to identify underlying issues and thus prevent future errors.

Hands-On Scenario

Jenny is a registered nurse with 4 years' experience working on the acute care ward. Following a shift change, he has been assigned to look after John, a 45-year-old male who was admitted following an acute asthma exacerbation in order that his condition could be stabilised. Jenny notes that John appears to still be struggling to breathe, as he is wheezing and very short of breath. John's face is pale, he shows signs of cyanosis of the lips and finger tips, and appears very distressed. On examining his notes, Jenny sees that 3 hours ago, following admission, John was reviewed by the doctor on shift, Dr Smith, who prescribed 5mg salbutamol via an oxygen-driven nebuliser to be repeated every 20-30 minutes as indicated, as well as 40mg of prednisolone orally, and 0.5mg ipratropium bromide four times daily, also by oxygen-driven nebuliser. However, when Jenny reviewed John's notes she sees that he has not yet received the 40mg of prednisolone or 0.5mg ipratropium bromide via nebuliser in the time that he has been on the acute care ward. John has in fact only received 2 doses of 5mg salbutamol via a nebuliser in that time. Jenny quickly identifies that the doctor's prescribed instructions have not been carried out. She sees that the nurse who administered the salbutamol, and failed to administer the prednisolone and ipratropium bromide, was her colleague, Susan.

Jenny quickly acts to alleviate John's symptoms and thus ensure his safety. She knows that salbutamol and ipratropium bromide can safely be co-administered, as they work by different mechanisms, so she quickly sets up these drugs to be delivered by oxygen-driven nebuliser. She sits with John to reassure and comfort him, and to monitor his vital signs, until she is satisfied that his symptoms are beginning to come under control and his discomfort and distress are reduced. Jenny records the error she has observed in John's notes, and the drug administrations she has just made of salbutamol and ipratropium bromide. As John begins to recover from his shortness of breath and wheezing to the degree where he can take oral medication, she administers the omitted 40mg of prednisolone and records this in the notes also. She informs John of the error that has occurred and apologises on behalf of the hospital and the nurse previously in charge of his care. Once Jenny is satisfied that John's condition has stabilised enough for her to leave his side, she immediately notifies Dr Smith, the prescribing doctor indicated in the notes. Dr Smith is concerned and agrees to prioritise reviewing John's condition to ensure that John is safe and has not been harmed by the incident. Jenny then notifies her line manager in line with her hospital's local policy. She then checks on John again to ensure he is stable. Together with her line manager, Jenny notifies Simon, the designated contact within the hospital trust indicated in the hospital's error reporting protocol and passes on the details of the nurse who made the administration error. Simon recommends that the NMC be informed of the error and that the institution carries out its own investigative procedure.

As part of the internal investigation, Jenny, Dr Smith and Susan are all asked for their accounts of the events. When interviewed, Susan becomes distressed at the thought of having endangered John's health and reveals that she feels the reason she made the error of omitting the prednisolone and ipratropium bromide dosages was due to having too many critical care patients to care for. She remembers administering John the prescribed salbutamol dose via a nebuliser as soon as she was able, but that she became distracted due to an alarm going off on another patient's monitor to indicate that their oxygen saturation levels had fallen below a safe level. Susan recalls hurrying to that patient, and immediately attempting to rectify that patient's hypoxia by increasing their oxygen flow. She was then distracted a second time by being called to a patient who was vomiting, and struggling to maintain their airway. As no other nurse was in sight, she therefore hurried to the second patient and performed the necessary emergency care to clear the patient's airway. When she returned to John, she could see that he was receiving his prescribed dose of salbutamol and appeared to be experiencing some relief in his symptoms. Susan recalled picking up the notes again and reading the first note about the salbutamol dosage, at which point she was then distracted a third time by another patient's heart rate monitor alarm going off. By the time she had finished with this third patient, she could only remember that John needed salbutamol and recorded the dose in his notes, but had forgotten that prednisolone and ipratropium bromide had also been prescribed. She then realised that she still had the medication needs of a further four patients to review urgently, and was concerned that they may be waiting for their medication. She assumed that she had met John's needs and recorded the administration as required. She assured the investigative team that this was the true reason why the error occurred and was very sorry that the incident had happened.

This investigation identified that although Susan had made the medical error by omitting to carry out all prescribed drug administrations, the real cause of the drug administration error was the lack of support that Susan had, and the lack of available staff to care for the other acutely ill patients on the ward. The investigation identified that Susan had administered urgent and emergency treatment to the other patients, whose safety would have been seriously compromised had Susan not taken the action she had. The investigation also discovered that on that shift, 3 registered nurses were absent due to sickness and this had left the ward short staffed, as the line manager had not yet managed to secure any bank staff to cover these missed shifts. The investigation also found that the 2 nurses who should have been available to help Susan cover all the acute care patients on the ward were otherwise engaged at the time, providing emergency care to another patient who had collapsed in the toilets. The accounts of all staff questioned supported Susan's story. It was therefore concluded that there was inadequate provision of staffing, and that the line manager had received inadequate support from management in sourcing bank nurses to cover the missing nurses. Susan was offered support by her line manager throughout the process and although the incident was officially reported and recorded, it was noted that the organisational issues that prevented her line manager from securing bank nurses were really at fault. This finding was supported by both the NMC and the CQC, who reviewed the investigation, and Susan therefore did not face significant disciplinary action.

The National Patient Safety Agency (NPSA) was also informed of the via the National Reporting and Learning System (NRLS). As well as ensuring that the management of the acute care ward learned from the error and reviewed the process for urgently hiring bank nursing staff to prevent it happening again, other hospitals also had the opportunity to enhance their safety practice by reviewing these events and considering the lessons learned from the point of view of other institutions.

Reference list

Baker, E. (2015). Transparency Will Only Change Culture If We Eradicate Blame as A Response. Care Quality Commission. [Online]. Available at: http://www.cqc.org.uk/content/transparency-will-only-change-culture-if-we-eradicate-blame-response [Accessed: 23 November 2016].

Beckford, M. (2011). Nurses Wear 'Do Not Disturb' Signs During Drug Rounds. The Guardian. [Online]. Available at: http://www.telegraph.co.uk/news/health/news/8728093/Nurses-wear-do-not-disturb-signs-during-drug-rounds.html [Accessed: 23 November 2016].

Colen, H. B., Neef, C. and Schuring, R. W. (2003). Identification and verification of critical performance dimensions. Phase 1 of the systematic process redesign of drug distribution. Pharmacy World & Science, 25 (3), pp.118-125.

Cottney, A. (2014). Improving the safety and efficiency of nurse medication rounds through the introduction of an automated dispensing cabinet. BMJ Quality Improvement Reports, 3 (1), p.u204237.w1843. [Online]. Available at: http://qir.bmj.com/content/3/1/u204237.w1843 [Accessed: 23 November 2016].

CQC. (2015). Statutory Notifications. Care Quality Commission. [Online]. Available at: https://www.cqc.org.uk/sites/default/files/20150331_100501_v6_00_guidance_on_statutory_notifications_ASC_%20IH_PDC_PA_Reg_Persons.pdf [Accessed: 23 November 2016].

Crouch, S., Crouch, M. and Chapelhow, C. (2007). Medicines Management: A Nursing Perspective. 1st ed. Harlow: Pearson Education.

Department of Health. (2013). NHS Constitution for England [Online]. Available at: https://www.gov.uk/government/publications/the-nhs-constitution-for-england [Accessed: 23 November 2016].

Department of Health. (2015). 2010 to 2015 Government Policy: Patient Safety. Department of Health. [Online]. Available at: https://www.gov.uk/government/publications/2010-to-2015-government-policy-patient-safety/2010-to-2015-government-policy-patient-safety [Accessed: 23 November 2016].

Ford, S. (2012). Drug Rounds Must Be Protected in Care Homes to Cut High Error Rates. [Online]. Available at: http://www.nursingtimes.net/nursing-practice/specialisms/older-people/drug-rounds-must-be-protected-in-care-homes-to-cut-high-error-rates/5040511.article [Accessed: 23 November 2016].

Ghaleb, M. A., Barber, N., Franklin, B. D. and Wong, I. C. K. (2010). The incidence and nature of prescribing and medication administration errors in paediatric inpatients. Archives of Disease in Childhood, 95 (2), pp.113-118.

Grissinger, M. (2010). The five rights. Pharmacy and Therapeutics, 35 (10), p.542.

Harvey, S., Murphy, F., Lake, R., Jenkins, L., Cavanna, A. and Tait, M. (2010). Diagnosing the problem: Using a tool to identify pre-registration nursing students' mathematical ability. Nurse Education in Practice, 10 (3), pp.119-125.

Hood, L. (2013). Leddy & Pepper's Conceptual Bases of Professional Nursing. 8th ed. Missouri: Lippincott Williams & Wilkins.

Jaques, H. (2012). Only One In 10 Doctors Is Confident in Effectiveness of Whistleblowing Procedures. 10 May. [Online]. Available at: http://careers.bmj.com/careers/advice/view-article.html?id=20007246 [Accessed: 23 November 2016].

Kowalak, J. P. (ed.). (2009). Lippincott's Nursing Procedures. 5th ed. Philadelphia: Lippincott Williams & Wilkins.

Lippincott. (2012). Nursing Pharmacology Made Incredibly Easy. 3rd ed. Philadelphia: Lippincott Williams & Wilkins.

Morello, R. T., Lowthian, J. A., Barker, A. L., McGinnes, R., Dunt, D. and Brand, C. (2013). Strategies for improving patient safety culture in hospitals: A systematic review. BMJ Quality & Safety, 22 (1), pp.11-18.

Nichols, P., Copeland, T.-S., Craib, I. A., Hopkins, P. and Bruce, D. G. (2008). Learning from error: Identifying contributory causes of medication errors in an Australian hospital. The Medical Journal of Australia, 188 (5), pp.276-279.

NMC. (2015a). Openness and Honesty When Things Go Wrong: The Professional Duty of Candour. Nursing and Midwifery Council. [Online]. Available at: https://www.nmc.org.uk/standards/guidance/the-professional-duty-of-candour/ [Accessed: 23 November 2016].

NMC. (2015b). The Code for Nurses and Midwives. Nursing and Midwifery Council. [Online]. Available at: http://www.nmc.org.uk/standards/code/ [Accessed: 23 November 2016].

NMC. (2016). Standards for Medicines Management. Nursing and Midwifery Council. [Online]. Available at: http://www.nmc.org.uk/standards/additional-standards/standards-for-medicines-management/ [Accessed: 23 November 2016].

Ramjan, L. M. (2011). Contextualism adds realism: Nursing students' perceptions of and performance in numeracy skills tests. Nurse Education Today, 31 (8), pp.e16-21.

Reason, J. (2000). Human error: Models and management. BMJ, 320 (7237), pp.768-770.

Rice, M. (2015). To Hear and Be Heard: Will Whistleblowing Achieve Culture Change? The King's Fund. [Online]. Available at: http://www.kingsfund.org.uk/blog/2015/02/hear-and-be-heard-will-whistleblowing-achieve-culture-change [Accessed: 23 November 2016].

Segal, J. B., Arevalo, J. B., Franke, M. F. and Palazuelos, D. (2015). Reducing dosing errors and increasing clinical efficiency in Guatemala: first report of a novel mHealth medication dosing app in a developing country. BMJ Innovations, 1 (3), pp.111-116.

Taxis, K. and Barber, N. (2003). Ethnographic study of incidence and severity of intravenous drug errors. BMJ, 326 (7391), p.684.

Westbrook, J. I., Woods, A., Rob, M. I., Dunsmuir, W. T. M. and Day, R. O. (2010). Association of interruptions with an increased risk and severity of medication administration errors. Archives of Internal Medicine, 170 (8), pp.683-690.

Wright, K. (2013). The role of nurses in medicine administration errors. Nursing Standard, 27 (44), pp.35-40.