Methodological Approaches to Pain Memory Assessment in Chronic Pain: A Scoping Review.

Pain memory refers to the ability to encode, store, and recall information related to a specific pain event. Reviewing its common features is crucial, as it provides researchers with a foundational guide for designing studies that assess pain memory in individuals with chronic pain. The primary objective of this study was to examine the common characteristics-particularly the methodological approaches-of existing research on pain memory in adults with chronic pain. A scoping review was conducted using PubMed and Embase as search databases. Studies were included if they met the following criteria. (a) It involved only adults with chronic pain and (b) assessed at least one of the following parameters: pain intensity or pain unpleasantness. The exclusion criteria were the following: (a) not having pain memory assessment as a primary objective, (b) including participants under 18 years of age, (c) involving individuals without chronic pain (e.g., those with acute pain or healthy participants), (d) lacking essential information, or (e) unavailability of the full text. From an initial pool of 4585 papers, 11 studies met the inclusion criteria. All studies exclusively involved adults with chronic pain, and all reported pain intensity, while only 27% assessed pain unpleasantness. Additionally, psychosocial variables were the most frequently reported non-pain-related outcomes. Regarding study protocols, most relied on daily data collection, with the most common recall period being within the first 48 h. The methodological characteristics identified in this review-particularly those with a high frequency of occurrence-should serve as fundamental guidelines for future research on pain memory in adults with chronic pain, and should be carefully considered by investigators in this field.