Unintended overexposure of a patient during radiotherapy treatment at the Edinburgh Cancer Centre, in September 2015

The report of a detailed investigation of an incident involving a serious overexposure to ionising radiation for a patient undergoing radiotherapy, in September 2015.

6. Training and entitlement of the operators concerned

6.1 General provisions for training and entitlement of duty holders

Regulations 4(4) and 11, together with Schedule 1(b) place duties on the employer to ensure that all 'referrers', 'practitioners' and 'operators' are 'identified as entitled to act' in these capacities, and to take steps to ensure that 'no practitioner or operator shall carry out a medical exposure or any practical aspect of a medical exposure without having been adequately trained'. Regulation 11(4) further requires that the employer shall keep appropriate training records for entitled practitioners and operators, and shall make these available for inspection by the appropriate authority, and Regulation 4(4)(b) requires that the employer shall take steps to ensure their continuing education and training.

The ECC provisions for training and for entitlement of duty holders are defined in Level 1 (see Sub-section 7.2.3 for an explanation of 'Levels') Employer's Written Procedures numbers EP1-1 and EP1-2, and in Level 2 Employer's Written Procedures numbers EP2\ ECC\0001, and EP2\ ECC\0002.

Employer's Written Procedures EP2\ ECC\0001, for 'The identification of individuals entitled to act as Referrers for therapeutic exposures, and as Practitioners or Operators for all medical exposures' includes a competency list for Therapeutic Radiographers and a competency list for Oncology Physics. For example, one such Radiographer competence is for the 'Pregnancy status check'.

Employer's Written Procedures EP2\ ECC\0002, for 'Induction of new staff and training and training records of entitled Practitioners and Operators' states that for Therapeutic Radiographers, the level of competence must be signed off by the Therapeutic Radiography Senior Manager or Head of Section for that area, and that this signature 'confirms that any relevant certificate of training has been inspected and that the assessor is satisfied that the person meets the competency requirements'. The reference to a 'level of competency', reflects the fact that 'levels' between 0 and 4 might be assigned depending on entitlement to practice unsupervised, to supervise trainees, or to provide training.

6.2 Training requirements for the radiographers

The treatment plans undertaken at the ECC range in complexity from what might be described, for present purposes, as 'simple plans' and 'complex plans' For example, planning for any treatment involving the use of a beam shaping device in the Linac head called a 'multileaf collimator' would fall into the 'complex' category.

All radiographers entering into training as a treatment planner would begin with training in 'simple planning' techniques, for which the ECC training requirements are defined in controlled document number EP2\ ECC\2036 'Training Plan: Radiographer Calculations'. Progression beyond this stage requires highly specialised additional training, and, in practice, only a small proportion of radiographers would pursue such a progression.

The training requirements for the manual calculations undertaken by radiographers relevant to this incident are, therefore, fully covered by EP2\ ECC\2036 'Training Plan: Radiographer Calculations', the latest version of which is 'Issue 1.0, dated 18 th February 2015. This includes a requirement for the trainee operator to undertake '10 (practice) calculations for parallel opposed fields', the 'Pass Criteria' being defined as 'Correct calculation and completion of document'. The 'document' referred to here is the ECC's pro-forma 'Practice Calculations' workbook, and EP2\ ECC\2036 includes a 'Signed (trainer)' field to indicate that the trainer is satisfied that the 'Pass criteria' have been met, and a 'Last step completed' field to indicate the date at which all requirements have been satisfactorily achieved.

Radiographers participating in these 'simple plans' should have also undertaken the training defined in ECC controlled document number EP2\ ECC\2037 'Training Plan: Data entry', which includes creation of a 'workspace' in the Aria computer programme. The information to be entered by the trainee planner into this workspace would include, (along with other patient data) the various parameters used in their manual calculations.

A further requirement for these radiographers is successful completion of ECC controlled document number EP2\ ECC\2038 'Training Plan: Sanctioning', which requires that the trainee demonstrate the ability to correctly check and verify a number of entries in the Radiotherapy Treatment Sheet, prior to this sheet being made available to the operators who deliver the treatment.

EP2\ ECC\2036 also includes a requirement for training in 'Export into RadCalc programme (to be within 2.5%)'. Though not stated explicitly, the ECC's Head of Therapeutic Radiography has stated that, in keeping with the documented training provisions for members of the Oncology Physics Department outlined here in Sub-section 6.5, this requirement is for the result of at least 15 manual calculations to have been checked by the trainee using the RadCalc dose verification programme. Each of these 15 computed results must agree with their manual calculation to within 2.5%.

None of Radiographers A, B, C or D had undertaken training in 'complex plans'.

Sub-section 6.3 of this report considers whether these training requirements had been properly completed and recorded for the radiographers involved.

6.3 Evidence of initial and continuing training for the radiographers

The training records for Radiographers A, B, and C include evidence of completion of training pro-formas EP2\ ECC\2036 'Training Plan: Radiographer calculations', EP2\ ECC\2037 'Training Plan: Data entry', and EP2\ ECC\2038 'Sanctioning'. Regarding EP2\ ECC\2036 the training records for each of these Radiographers also included a completed pro-forma booklet of 'Practice Calculations for Parallel Opposed Treatments' which includes practice calculations for isocentric treatments, and for parallel opposed pair treatments to both equal and unequal FSD.

The pro-forma booklet of 'Practice Calculations for Parallel Opposed Treatments' is not held as a quality controlled document.

In all cases, however, there are deficiencies in record keeping including missing signatures and dates, and records showing a date of completion of training that is some years earlier than the recorded date of last review on the pro-forma in which they appear. This latter anomaly has been explained by the Head of Therapeutic Radiography in terms of development of the document quality system. On replacement of informal training records with quality controlled documents, these informal records were, in many cases, discarded and the dates of completion of training elements were recorded on the new quality controlled pro-formas as the date shown on the discarded document. However, because of this practice, useful evidence of completion of training has clearly been lost, and this issue should be considered in any review of training records arising from the recommendations of this report.

The training records for Radiographer D include evidence of completion of ECC training document EP2\ ECC\2055 Training Plan Summary for On-call Entitlement'. For the various training elements listed therein, the 'Date of Completion' is recorded and being between 2006 and 2014.

For Radiographer D, there is no evidence of completion of training pro-formas EP2\ ECC\2036 'Training Plan: Radiographer calculations', EP2\ ECC\2037 'Training Plan: Data entry', and EP2\ ECC\2038 'Sanctioning'. This is explained by the fact that this radiographer qualified before the others, and his equivalent training and entitlement preceded the introduction of these documents.

Regarding practice calculations the training record for Radiographer D showed evidence of one such calculation having been completed successfully for an isocentric parallel opposed pair treatment.

There is no written record for any of these four Radiographers of successful checking of 15 (or any) manual calculations using RadCalc.

Regarding the 'competency requirements' referred to in the final paragraph of Sub-section 6.1, there is a lack of clarity in currently in ECC documents about exactly which training should be undertaken, and how this should be followed by actual treatment plans carried out under direct supervision, prior to entitlement for specific competences, and about how that training and experience should be formally recorded and records retained.

In summary, the training records for these operators provide evidence of completion of relevant initial training, and some indication of relevant continuing professional development. However, a number of deficiencies in the keeping of training records have been identified and this is discussed further in Section 9 of this report. Concerns regarding maintenance of competence for these infrequent treatment plans are also discussed in Section 9.

6.4 The scope of entitlement for the radiographers

The ECC's Level 3 Employer's Written Procedures number EP2\ ECC\2000 comprises a set of tables wherein all current Therapeutic Radiography staff are listed in rows and the relevant operator competences for which these staff might be entitled are listed in the associated column headings.

Each cell in the table is completed by the Head of Therapeutic Radiography with a number between 0 and 4, to indicate the level of competence of the operator concerned for carrying out that task, and for training and supervising others. 'Level 0' indicates that the Therapeutic Radiographer is not entitled to undertake any practical aspect of the competence concerned, even under supervision, 'Level 1' indicates authority to undertake practical aspects of the competence under supervision, 'Level 2' indicates authority to act without supervision, and Levels 3 and 4 confer authority for training and supervision.

The total of those competences assigned to the operator by the Head of Treatment Radiography at Levels 1 to 4 comprises the 'scope of entitlement' for that operator.

Among the competences listed in Employer's Written Procedure number EP2\ ECC\2000, the one of principal relevance to this particular incident is 'On Call (combined Pre-treatment and treatment preparation/delivery/verification)'. In practice, any operator designated at 'Level 2' or above is thereby entitled to undertake all aspects of pre-treatment imaging, manual treatment planning and checking, data entry to Aria, independent MU checking using RadCalc, final treatment approval, treatment delivery, and verification using on-treatment imaging (whether 'on-call' or during normal working hours). In addition, however, this 'On call' competence has been separated into its individual elements, for example, 'Treatment Preparation' and 'Treatment Delivery', and the levels of entitlement have been separately assigned and documented in a similar fashion for each.

At the time of this incident each of Radiographers B, C, and D had a documented Level 2 assignment for all of this 'On Call' competence, and for 'Treatment Preparation', which includes manual planning and the use of RadCalc. Hence they were deemed by the Head of Therapeutic Radiography to be competent to undertake all relevant aspects of the manual and RadCalc calculations.

Radiographer A, however, had a Level 1 assignment, which indicates that he should have undertaken the manual calculation under direct supervision by an operator at Level 2 or above. However, this has been explained by the by the Head of Therapeutic Radiography as an error in record keeping, and evidence has been provided that, as discussed in Sub-sections 6.2 and 6.3 of this report, Radiographer A had undertaken all the training necessary for a Level 2 assignment for (at least) the manual calculations aspect of this 'Treatment Preparation' competence.

The finding of this investigation is, therefore, that each of Radiographers B, C, and D were properly trained and entitled to undertake the manual and RadCalc calculations. While the training records for Radiographer A, indicate that he was adequately trained to undertake manual calculations unsupervised, his scope of entitlement did not reflect this, and this is a serious error in record keeping.

Further to this, all operators should have a clear understanding of their own scope of entitlement, which should not be exceeded. At interview, it was clear that Radiographer A lacked a clear understanding of the relationship between training and entitlement by the employer, and of how his documented scope of operator entitlement could be accessed.

In summary, this investigation has identified a number of concerns about the current system for assessing and recording of the scope of entitlement for treatment radiographers and for linking entitlement to recorded training. These concerns are discussed further in Section 9 of this report.

6.5 Training requirements for the physicist

Physics staff at the ECC come under a different management structure to that for the therapeutic radiographers, and have different training programmes. The principal training document relevant to this incident for Physicist A is EP2\ ECC\3030 'Manual Calculations', associated with which are a number of other documents relating to specific area of the overall training provisions required by EP2\ ECC\3030.

EP2\ ECC\3030 includes a requirement for the trainee operator to successfully undertake a minimum of 15 practice examples, and a minimum of 10 real patient calculations under supervision, using the 'independent monitor unit system' (RadCalc).

6.6 Evidence of initial and continuing training for the physicist

The ECC training plan, EP2\ ECC\3030 'Manual Calculations', for Physicist "A" was completed in August of 2012 and was signed off by the then Head of the ECC Treatment Planning Section. This includes confirmation that the following training elements have been completed successfully:

i. EP2/ ECC/0050 'External Beam Protocol'; a departmental overview of provisions for identification of the area of treatment, treatment planning, and treatment delivery.
ii. EP2/ ECC/3040 'Treatment Planning' and associated training documentation for trainee planners.
iii. EP2\ ECC\3402 "Calculating and Checking Monitor Units for Photon Beam Treatments-Manual Calculations"
iv. A minimum 15 practice calculations of various types, including parallel opposed pairs, as laid out in the associated (uncontrolled) document 'Training Progress for Manual Calculations', the results of which are recorded on 'Manual Calculations Record of Evidence'. This includes both manual calculations and verification of the manually calculated Monitor Units using RadCalc.
v. Ten calculations under supervision for patients undergoing treatment, the results of which are recorded on the associated 'Manual Calculations Record of Evidence' pro-forma'.

Regarding points iv and v above, sign-off by the then Head of the ECC Treatment Planning Section confirms that the various elements required by EP2\ ECC\3030 'Manual Calculations' have been completed. However, because of an instruction issued by the Head of Oncology Physics that the associated 'Records of Evidence' did not need to be retained following sign-off, completed versions of these documents for Physicist A were not available. This is discussed further in Section 9.

6.7 The scope of entitlement for the physicist

Entitlement for members of the ECC Treatment Planning Section is recorded in quality controlled document EP2\ ECC\3002 'Entitled Staff List - Treatment Planning Operators'. This document includes a list of the competences against which staff may be entitled at either of levels '1' or '2'.

Under current provisions either one or both of the required treatment planning calculations for each patient must be carried out by an operator who is entitled at Level 2.

The competence relevant to the role of Physicist A in this incident is listed in EP2\ ECC\3002 as 'Manual Calculations, Templates & Finishing Off', for which Physicist A is recorded as having been entitled at Level 1.

Normally, this would mean that the involvement of Physicist A with a plan of this type would be alongside a treatment planner entitled at Level 2. In this case, however, the role of Physicist A was not as a planner of this particular exposure, but as a consultant on the use of RadCalc. The relevance of his entitlement is that it demonstrates that Physicist A had successfully demonstrated initial competence in the use of RadCalc. The question that then arises is whether this initial entitlement could be supported with evidence of relevant continuing training and/or experience in the use of RadCalc.

In this regard, Physicist A's record of 'continuing personal development' ( CPD) shows considerable experience in the use of RadCalc, including training of radiographers in its use. Indeed, Physicist A has been described by the Head of Oncology Physics in the course of this investigation as the 'go-to' person for advice on the use of RadCalc. The 'Level 1' (rather than Level 2) designation for the 'Manual Calculations, Templates & Finishing Off' competence for Physicist A was explained in terms of the breadth of the tasks included in this competence, in addition to the use of RadCalc.

The finding of this investigation is, therefore, that with regard to Regulation 11(1), Physicist A had been 'adequately trained' for the 'practical aspects' of this exposure in which he participated, and was an appropriate person from whom to seek advice. However, there is clear evidence to suggest that the application of the training and expertise of Physicist A had been compromised by recent changes in the Employer's Written Procedure for the use of RadCalc for 'parallel opposed fields', for which no additional training had been given.

The differences between the way that the scope of operator entitlement is defined and recorded for the Physicists and the Radiographers is also of concern, and this is also discussed further in Section 9.


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