Ever wonder why ISO or CLSI glucose standards use primarily one set of limits rather than an error grid? Here’s my explanation.
With an error grid – especially a glucose error grid – there are multiple sets of limits. Data inside of the innermost limit implies no harm to patients and data outside of the outermost limit implies serious injury or death. And of course there are limits in between the inner and outermost limits which range in harm to patients. Although the limits are provided without percentages of data that should be in any region, it is implied that there should be no results in the outermost limits.
With ISO or CLSI, the use of one primary set of limits (corresponding to the innermost limits of an error grid) relieves these standard organizations from having to even mention a case where serious injury or death may occur. And this is probably because these groups are dominated by regulatory affairs people from industry.