Assessment of physical activity by movement registration systems in chronic pain: methodological considerations.

OBJECTIVES: Physical activity assessments in chronic pain research have mostly been based on self-report. However, earlier research indicated that chronic pain patients have difficulties in estimating their own daily life activity level. Movement registration systems have been introduced to overcome the limitations of self-reported measures. However, no uniform guidelines for researchers on how to analyze and interpret movement registration data in chronic pain exist. The aim of the study was to provide recommendations for physical activity assessment based on movement registration in patients with chronic pain.
METHODS: First, a systematic review of the procedures and data processing techniques used in movement registration for chronic pain patients will be performed. Second, it will be discussed whether the recommendations for physical activity assessment in healthy individuals are applied in chronic pain research. Last, recommendations regarding assessment procedure and data processing for using movement registration systems in future research in patients with chronic pain will be given.
RESULTS: In chronic pain literature, 27 articles on movement registration were identified. According to the recommendations for activity assessment in healthy individuals, the various descriptions of the assessment procedures in these articles were mostly limited. Especially, information regarding the minimal requirements for the assessment period and the method used for calculation of the final outcome variable were often lacking. DISCUSSION: It is recommended that studies in chronic pain research explicitly apply and report the criteria that have been used to define an assessment day, the total assessment time, and the method for calculating the final test outcome.