Technical Report: Proper Task Instructions and the Two-out-of-Five Test

Difference tests continue to play a prominent role as businesses investigate the sensory effects of ingredient or process changes. Even so, the importance of correct instructions in these tests is not always appreciated- incorrect instructions can reduce the ability of a test to detect real differences. The effect of instructions on the outcome of sensory difference testing was recognized when the difference between the 3-AFC and Triangle test was explained and when the relative power of difference testing methods was explored. This topic has resurfaced as other difference testing methods, such as the Two-out-of-Five test, have become more commonly used. In this report, we explain how incorrect instructions can sabotage a method, and we provide guidance for the optimal set of test instructions for the Two-out-of-Five test.

This technical report appears as:
Ennis, J. M., Rousseau, B., and Ennis, D. M.  (2012). Proper Task Instructions and the Two-out-of-Five Test. IFPress, 15(4) 4-5.

Colleagues can download this technical report here:
Proper Task Instructions and the Two-out-of-Five Test

Not a Colleague? Click here to join for free!

This technical report also appears in our book, Tools and Applications of Sensory and Consumer Science.

Upcoming Webinar

September 21, 2017

Large TURF Problems: Finding Custom Solutions


Announcing the release of the 2016 Webinar Series Package!

Offered at a discounted rate of 50% off regular price, this package contains recordings of all four webinars offered during the 2016 Quarterly Webinar Series.

Create Your Own Webinar Package


Webinar calendar


Become a Colleague!

Join now to gain access to our technical reports, presentations, and more!

Click here to login or join.

Student Award

Now accepting applications for the
2017 Institute for Perception Student Award

site search