Selective processing of threat‐related cues in day surgery patients and prediction of post‐operative pain

Objective: To investigate the use of a measure of selective processing bias associated with anxiety as a predictor of post‐operative pain independently of self‐report measures of anxiety. Methods: Forty‐seven women admitted for minor gynaecological surgical procedures completed a selective processing task (modified Stroop) and the State‐Trait Anxiety Inventory immediately prior to surgery. Following surgery they completed the McGill Short‐Form Pain Questionnaire. Intraoperative analgesia consumption was also recorded. Results: Participants demonstrated significantly slower colour‐naming times for physical threat cues than control cues. This was not due to an emotionality effect, as colour‐naming times for neutral and positive cues were not significantly different. This bias was congruent with the participants’ current concerns, as colour‐naming times were significantly slower for physical threat words than for social threat words. This index of selective processing bias significantly predicted post‐operative pain independently of self‐reported state and trait anxiety. Conclusions: The advantages of measures of psychological constructs that are not reliant on self‐reporting are discussed.