A systematic review with subset meta-analysis of studies exploring memory recall biases for pain-related information in adults with chronic pain

Pain-related memory biases have been frequently explored in individuals with chronic pain, and along with attentional and interpretation biases are hypothesised to contribute to the onset and/or maintenance of chronic pain. The aim of this review is to provide a systematic review and synthesis of studies exploring memory recall biases for pain-related information in individuals with chronic pain relative to healthy controls and the recall of neutral information. Studies were identified through a search of Medline, PsychINFO, Web of Science, CINAHL, Cochrane Library, and Open Grey databases. Search terms were memory, recall, recognition, and bias*, intersected with pain. Eighteen studies meeting the inclusion criteria were included. Subset meta-analyses are also reported from 12 studies with relevant between-groups data (comparing recall in chronic pain vs healthy control groups) and 12 studies with relevant within-groups data (eg, comparing recall of pain-related/emotional vs neutral words). Between-groups analysis revealed significantly weaker recall bias for affective-pain words in individuals with chronic pain relative to healthy controls, but only when nondepressed chronic pain individuals were included. No significant differences were found between groups in the recall of sensory-pain, illness-related, or depression-related words. Within-groups analysis revealed individuals with chronic pain show a significant recall bias favouring sensory-pain words relative to neutral and affective-pain words, and a bias for illness-related words relative to depression-related words. A recall bias favouring neutral words was found in healthy individuals. Evidence for the presence of pain-related memory biases in patients with chronic pain is inconclusive. Further methodologically rigorous research is required.