The post-analytical procedures performed within the
laboratory include verifying laboratory results, feeding
them into the laboratory information system, and
communicating them to the clinicians in a number of
ways (in particular, by producing a report and making
any necessary oral communications regarding ‘‘alert’’
or panic results). In this step, the most common mistakes,
accounting for 18.4–47% of total laboratory
errors, are: wrong validation, results that are delayed,
not reported or reported to the wrong providers, and
incorrect results reported because of post-analytical
data entry errors and transcription errors (11, 54).
Manual test validation is a time-consuming process
with large inter-individual variation; moreover, it
slows down the response of the laboratory to the clinic,
thus causing delay in the diagnostic and therapeutic
process. This validation process can be automated;
some automated validation systems with satisfactory
sensitivity and specificity have been developed and
introduced into clinical laboratories (55, 56). As yet,
however, it has not been proven that validation systems
allow clinical laboratories to reduce errors, thus
improving patient safety and outcomes. This is owing
to difficulties in performing longitudinal studies with
a design that allows the identification of real errors
and a comparison with historical error rates. However,
validation systems may be considered valid ‘‘preventive
action’’. Another well-recognized source of
post-analytical problems is inter-laboratory variability
and inaccuracy of reference intervals (57–60). Reference
intervals for healthy subjects and diseased populations
are important benchmarks for the clinical
interpretation of laboratory test values. The use of different,
sometimes erroneous, reference intervals may
markedly affect the clinical interpretation of laboratory
data, leading to errors in clinical decision-making
(57). The production and release of the laboratory
report is the crucial step in post-analytical procedures,
as its format, content, and communication significantly
affect the interpretation and utilization of
laboratory data by clinicians. The importance of information
technology in improving reliability and security
of result reporting is widely recognized.
Requirements for information technology in laboratory
medicine now go well beyond the provision of
purely analytical data and include fundamental
aspects of data communication, namely the notification
of results that fall within established critical or
alert intervals (61). In particular, the possible role of
interpretative comments in improving patient outcomes
has generated a lot of interest. Guidelines for
the provision of interpretative comments have been
released (62) and schemes for assessing the quality
of comments have been initiated (63). The results
obtained indicate that interpretation provided by laboratory
professionals with inadequate expertise can
be dangerous, and highlight the need for improve-