ISO7064-standardised Check Digits
Applied to Blood Bag Numbers
| Hints to software developers |
Check digit procedures from ISO standard 7064 are
"state of the art" according to the quality requirements for their
intended use. Other check digit algorithms may have serious deficiencies and are
not recommended to be used. MOD11,10 algorithm provides an appropriate level of
reliability to enhance blood product bag identification in haemotherapy.
For the development of systems for workflow support and documentation it is
recommended:
Software at blood donations center site
- Newly developed software must enclose a MOD11,10 check digit into
identification numbers on both blood product bags and any type of
accompanying documents as well. Running system shall be upgraded as soon as
possible.
- It is not subject of this guideline, if and how the BDS applies
"internal" check digits to enhance quality security of preparation
workflow. BDS-internal check digits may be cut before the calculation of
external relevant check digit. This may be useful to meet international
Eurocode data structures or national agreements.
- The vendor of blood products has to inform his customers in time about any
changes in data structures.
Software at blood product customers site
- Newly developes software must provide decoding of MOD11,10 check digits to
detect transmission or storage errors. Running software shall be upgraded as
soon as possible.
- Check digit proofreading shall be applied to any type of data entry such
as via keyboard, barcode, OCR, mobile storage media, and remote access.
- The software must be customiseable to activate or deactivate check digit
proofreading dependent the specific vendor.
- The software may be prepared to support different ISO check digit
standards. Details are not subject of this guideline.
- The software may support additional plausibility checks of country codes,
BDS code, and/or other characteristics. Details are not subject of this
guideline.
- The Eurocode blood product bag number has to be stored completely at any
step of documentation at the blood product customers site. Never cut the
check digit!
- If the software has detected an "invalid" input it must present
a well designed error dialog asking the user for correct input. The error
event has to be alerted to the system administrator and logged including any
event attributes such as input source, input values, time, user identity,
and user response. Alerting and logging will allow to detect the presence or
absence of improper user actions, problems with IT-equipment and to manage
troubleshooting at both the consumer's and vendor's sites. Log files should
be archived to enable proof of input and storage quality retrospectively in
case of subsequent medical or legal events.
- If the software allows entry of "invalid" bag numbers
(recommended) there must be a user dialog stating the consequences of
entering "invalid" numbers.
- Additional advise may be requested from the authors.
