Follow-on tests: how to request them

(Aotea News, June 2011)

Occasionally, abnormal test results indicate additional testing is needed, and we perform a number of these follow-on -- or ‘reflex’ -- tests as part of our standard testing protocols.

We can also do follow-on testing after a referring practitioner has received a result, assessed it, decided that additional testing is required and informed us of this.

The laboratory is not, however, able to respond to “If..then” requests from referrers. (By “If... then” we mean: “Please perform Test A, and if the result is X then please add Test B.”)

The difficulties of “If...then” testing

Follow-on testing may shorten the time to diagnosis and save the patient from having a second specimen collected, but it creates many difficulties for the laboratory.

For instance:

  • the sample needed for the reflex testing may not be available
  • the time taken for the initial testing compromises the quality of the specimen
  • the patient may not have been properly prepared (fasted, for example)
  • the request received is not sufficiently specific as to what tests are needed.