Event Coding

Event Coding

Overview

All events must be coded as to what happened and where in the process they occurred. There are two code lists:

The first list encompasses the process steps involved from drawing a donor up to distributing products for patient or manufacturing use.
The second code list includes the process steps for receiving products into a transfusion service through administering products to a patient.

If an organization draws donors and issues products for patient use, both code lists should be utilized.

The code lists are organized by major process steps such as order entry, testing and product administration. Although some processes are carried out in multiple places in actual operations, an attempt was made to organize the process steps in chronological order.

Each process step is broken down into sub-process codes – each a further description of what went happened or almost happened. It is recognized that the list of sub-processes is not exhaustive. While it is desirable to maintain a stable code list, it is also recognized that the list will need to evolve over time. As needs for changes arise, please contact the MERS-TM staff.

Each event has a minimum of three event codes assigned to it:

Where in the process the event was detected (consequent/discovery event)
Where in the process the event first occurred (initial antecedent/occurrence event)
Where in the process did the most significant antecedent occur; i.e. the antecedent event most amenable to process improvement (this may be the same as the initial antecedent)

Assigning Consequent Event Code

Every event must have a consequent event code. The consequent event code is recorded on the QA SysOp Investigation Report (question 1).

The leading digit of the consequent event indicates the overall event type. The possible event types are misadventure, no harm event, near miss unplanned recovery and near miss, planned recovery. The code for each of these event types is 1,2,3 and 4 respectively.

Next, the consequent event process code is determined. Two initial questions are asked:

Did the event affect the safety, purity, potency, and/or efficacy of a product?
What process was being performed when the event was discovered?

Based on the answer to the first question, one of two coding tracks is chosen.

If safety, purity, potency, and efficacy is affected, the code reflects where in the process the product is located when the event is discovered.

Example – If in the process of issuing products it is discovered that a special processing step was omitted, the consequent event would be that an incompletely processed unit had almost been issued. The "issue" process code would be chosen.
If the safety, purity, potency, and/or efficacy of the product is not affected, then the second track of coding selected.

Example – A technologist initials an issue record where a signature was required and the event was discovered two days after the product was administered. Describing the consequent event with the ‘Product Administration’ process codes would imply there was a problem with the product itself. The event occurred in the issue process and was detected during a review of issue records. Therefore, both the consequent and initial antecedent events are coded within ‘Product Issue’ category.

The process steps are roughly listed in chronological order. Scan the list and determine which process category fits the event under investigation.

Example – if an event is discovered during testing of the patient sample, Sample Testing (ST) is the process code for the consequent event.

Once the consequent event process code is determined, select the sub-process numerical code that best describes the event.

When looking at frequency distributions of the consequent event process codes, it is important to remember that the consequent event is an indication of where events are being discovered, not necessarily where systems weaknesses exist. It is important to look at consequent process codes in conjunction with event type.

Assigning Antecedent Event Codes

Every event will have at least an initial antecedent (occurrence) event code listed on the QA SysOp Investigation Report (question 2). If the event undergoes a causal analysis, up to four antecedent events may be included in the Root Cause Analysis Report.

The process for assigning process codes to antecedent events is the same as for consequent events.

Example 1– If a test result was misinterpreted, the process code would be Sample Testing (ST).
Example 2 – If a product was split that should not have been, the process code would be Product Manipulation (UM).

Once the process code is determined, chose the sub-process code that best describes the antecedent event.

Assigning Significant Antecedent Event Codes

The significant antecedent is the event chosen by the QA SysOp as being the most likely to benefit from a process improvement. If the event as a whole is relatively simple and has only one antecedent event, then this will be the only choice for the significant antecedent event.

Indication of a significant antecedent event is not a promise of a process improvement.
The process of assigning a process and sub-process codes to the significant antecedent event is the same as for other antecedent events.