The most commonly used technique without "control" questions is the relevant/irrelevant (R/I) "test." Instead of comparing reactions to relevant questions against reactions to "control" questions, the polygrapher asks a series of relevant questions several times, each time in a different order. If the examinee reacts strongly and consistently to a relevant question, then he is deemed to be deceptive.
One approach to countermeasuring the R/I technique is to augment reactions to two different relevant questions during each question series, in order to prevent reactions to any single relevant question from standing out.
However, because of the very high false positive rate that would be expected with the R/I technique, it
might be easier to explain away any reactions than it would be with a probable-lie CQT, and behavioral countermeasures (see Ch. 4 of
The Lie Behind the Lie Detector) might be enough to get one through the ordeal.
If the polygrapher sees no significant reaction to any of the relevant questions, he may throw in a "control" question to see if the examinee will show a reaction to that. A common way of doing this is to mis-state an irrelevant question that has previously been reviewed, for example, by asking, "Were you born on June 19th, 1980?" when it had previously been made clear that your birth date was June 9th, 1980. In other cases, a standard probable-lie "control" question may be inserted. If a "control" question is added to a relevant/irrelevant question series, then it would be beneficial to show a reaction to it.
In addition, some polygraphers may use announcements of the beggining and ending of the examination as a sort of "control" stimulus against which reactions to relevant questions will also be compared. Before asking the questions in a series, the examiner will state, "The test is about to begin." And at the end, he will state, "The test is now over." It would be beneficial to show a reaction to these announcements, too, if made.
For further reading on the R/I technique, see
TLBTLD (p. 115 ff. of the 3rd ed.).