Radiation is used in medicine for diagnosis and/or treatment. For example, X-ray machines and CT scanners are used to evaluate the extent of the injuries, such as bone fractures; or illnesses, such as heart problems. Radiotherapy - linear accelerators (LINACS) are used in medicine to irradiate and kill cancerous cells. Radiopharmaceuticals are used in the field of nuclear medicine as radioactive tracers in medical imaging and in therapy for many diseases. Typical incidents occur when:

  • the wrong patient is imaged or treated
  • the wrong quantity of radiopharmaceutical or radiation is delivered
  • the imaging is performed on the wrong body part of the patient.


Human error

The majority of medical radiation incidents are caused because of human error. The human causes of these incidents include:

  • Procedures not followed:
    In some occasions, procedural steps are inadvertently missed. On other occasions, practices deviate from a defined procedure because it is perceived that there is a better or more efficient way to perform the job. These changes may remove safety controls, change existing risks or introduce new risks. Reports also show that frequently incidents occurred because an initial error went unnoticed as a result of the omission of quality control and checks.

    Common procedures that are not followed include those for:
    • Patient identification
    • Verification that the prescribed treatment described in patient notes and booking systems agree.
  • Communication Issues:
    Incident reports show that problems with verbal, written or electronic communication often cause or contribute to incidents.

    Common communication issues include:
    • Misreading requests – Prescriptions and orders for treatment are sometimes handwritten and hard to read. This can lead to the wrong treatment or the wrong patient being treated.
    • Poor verbal communication – Reports indicate the importance of communicating with the patient to ensure that the correct patient and treatment is delivered. Communication problems with patients could occur as a result of age related conditions (e.g. deafness or the patient’s medical condition (e.g. Alzheimer disease). Reports also highlight potential for communication issues between medical staff.
    • Electronic communication. A number of reports highlight a failure in electronic ordering systems. These are sometimes associated with a treatment cancellation or change which has not been communicated before the treatment has commenced.
    • Misread labels – Some reports show that patient notes or the labels of radiopharmaceuticals are read incorrectly.

Patient factors

Some medical incidents are caused by factors that are largely beyond the control of medical staff. The most common incident reported is with patients who are unknowingly pregnant at the time of the procedure. It is standard practice for medical staff to ask a patient if they could be pregnant so that an informed decision is taken on whether the procedure should be undertaken. Reports indicate that this standard practice happens in nearly all cases.

Other patient factors include:

  • people who decide not to go ahead with a procedure after it has commenced; this results in an incident because a radiation dose has been received for no clinical benefit.
  • medical complications during surgery that uses interventional radiography may result in a higher dose of radiation than originally estimated.

Technology factors

Technological causes of these incidents include:

  • Equipment breaks down: the machinery used to undertake the treatment or diagnosis can break-down unexpectedly and scans or treatments need to be repeated.
  • IT failures: the computer system recording the image the apparatus (such as X-ray or CT scanners) is detecting may malfunction, resulting in the procedure requiring to be repeated.
  • Communication failures: faxed requests or cancellations are not received because the fax machine or computer failed. Some incidents occur when duplicate orders are received.

Organisation factors

Organisational causes of incidents include:

  • Human performance: Human error is the most common cause of incidents and the most common corrective actions are to remind staff how to correctly carry out the task and to require staff to be retrained. Reports suggest that underlying systems to ensure that human performance is achieved and maintained is not always effective at preventing incidents from occurring.
  • Quality control and monitoring: the organisation not monitoring staff practices to ensure procedures are followed.
  • Work overload: A number of reports show that workers can at times become overloaded from high demand for their services. Overload is known to cause an increased rate of human error.

Access to information FOI disclosure log Information public scheme