The delta check
is a measurement of the difference between a patient's sequential test results.
In an analysis of simulated delta check
rule performance, Strathmann and colleagues (6) found that the mean red blood cell volume (MCV) had the highest positive predictive value and the fewest false positives.
Therefore, much has been done to try to prevent it, and several result verification methods, such as delta check
(1) and multivariate delta check
(2), have been developed to detect it.
Munoz (2) reported on the practices of 340 laboratories for repeating critical values and delta check
values, from a 2007 survey.
violations should be investigated before reporting the current value.
limits that have been recommended for sodium are 5% and 10 mmol/L.
We would like to begin by using delta check
values that other places have used.
We picked up the error when a delta check
was done on one of the patients when a follow-up lab was ordered.
Initially, a delta check
is performed at the CBC workstation.
Protocols for rerun criteria, delta checks
, reflex testing, and sample flagging can be automated.
These detection schemes, referred to as limit checks and delta checks
, respectively, are in common use.
Other examples include the use of delta checks
, limit checks, and monitoring of the mean value calculated from patient test results.