The ISO guidelines for blood glucose meters are a detailed set of standards which blood glucose meters should meet.
The name ISO stands for International Organization for Standardizatio, the organisatio, based in Geneva, Switzerland, that is responsible for defining the standards.
Currently, the set of standards which need to be met are the set of standards that were published in 2003 (ISO: 15197:2003). In 2013, an updated set of standards (ISO: 15197:2013) were published and these newer standards will need to be met blood glucose meter manufacturers by the end of May 2016.
What do the ISO standards require?
The ISO standards have a number of different components which need to be met. The 2003 ISO standards included system accuracy and user performance components.
The new 2013 ISO standards included additional components such as:
- Evaluation of instructions of use
- Influence quantities of interfering substances
The system accuracy requirements are carried out by comparing blood glucose results of meters against the glucose level provided by a laboratory measurement. The YSI 2300 STAT Plus glucose analyser is able to perform the laboratory measurement.
The user performance evaluates the accuracy when the testing is performed by patients.
The evaluation of instructions for use is designed to evaluate whether the instructions for the meter are clear enough.
The influence quantities of interferents tests whether the meter can perform effectively for testing blood that has different levels of substances that could interfere with the result of the test. 24 potential interferents are listed by the ISO 2013 standards and these substances include haematocrit levels (the volume of red blood cells in the blood), cholesterol levels and levels of common drugs such as ibuprofen.
ISO system accuracy standards for blood glucose meters
Currently blood glucose meters need to meet the system accuracy standards of 2003 (ISO: 15197:2003) which state that 95% of blood glucose results should be:
- Within ± 0.83 mmol/L of laboratory results at concentrations of under 4.2 mmol/L
(Within ± 15 mg/dl of laboratory results at concentrations of under 75 mg/dL)
- Within ± 20% of laboratory results at concentrations of 4.2 mmol/L (75 mg/dL) or more
In 2013 new, tighter accuracy standards (ISO: 15197:2013) were drawn up, requiring that 95% of blood glucose results should reach the following standard
- Within ± 0.83 mmol/L of laboratory results at concentrations of under 5.6 mmol/L
(Within ± 15 mg/dl of laboratory results at concentrations of under 100 mg/dL)
- Within ± 20% of laboratory results at concentrations of 5.6 mmol/L (100 mg/dL) or more
The 2013 guidelines also now stipulate that 99% of readings must fall within zones A and B of the Consensus Error Grid for type 1 diabetes.
Blood glucose monitor manufacturers must ensure their blood glucose meters meet the 2013 accuracy standards by the end of May 2016
What do the ISO standards mean for people with diabetes?
The ISO standards are important for ensuring the blood glucose monitors we use are sufficiently reliable on a day to day basis. The move to the tighter 2013 standards is a positive advance as it will mean blood glucose meters will need to be more accurate and therefore provide greater confidence to us as users of the meters.