A comparison of laboratory measures of escape and avoidance behavior

Escape and avoidance of the onset of pain and exacerbations of pain can be difficult to distinguish in certain circumstances. This investigation compared measures of participants' (N = 61, 50.8% women) escape and avoidance behavior during an ischemic pain task. Instructions for the ischemic task were manipulated so that one group stopped the task whenever they wanted (eg, before the onset of pain) and another group endured the ischemic pain to tolerance. Delay time before beginning the task and willingness to complete the task were not related to self-reported escape/avoidance (r = -.21, P = .10; r = -.14, P = .30). Also, they were not predicted by fear, anxiety, or catastrophizing. Task duration with the unrestricted stop rule was not related to self-reported escape/avoidance (r = -.13, P = .50) and was not predicted by fear, anxiety, or catastrophizing. However, task duration with the tolerance stop rule was associated with self-reported escape/avoidance (r = -.40, P = .02) and was predicted by catastrophizing (t(29) = -2.92, P < .01). Thus, evidence for the validity of task duration with a tolerance stop rule as a measure of escape from pain or avoidance of pain exacerbation was found.

Measures of avoidance of pain onset were not supported. However, task duration was a valid measure of escape from pain or avoidance of pain exacerbation with tolerance stop rules. Other measures of escape/avoidance behavior and participants' perceptions of stable or increasing pain level throughout a pain task should be examined.