Longitudinal Study of Chronic Postsurgical Pain in Children and Adolescents

Chronic postsurgical pain as defined by the International Association for the Study of Pain, i.e.: greater than minimal pain (pain intensity ≥ 3) on more than 50% of a 7 days period, and impairment in health-related quality of life (score of < 74.9 on the Pediatric Quality of Life Inventory, PedsQL). This results in a binary outcome: chronic postsurgical pain yes vs no.

Description of pain trajectories over time, i.e., from baseline through FU3 (at 12 months after surgery). We will estimating group-based trajectory models using participants' Numeric Rating Scale (NRS) values of pain intensity at each time point. Higher ratings on the numeric rating scale indicate more pain.

Description of emotion-related trajectories over time, i.e., from baseline through Follow-up 3 (at 12 months after surgery). We will estimating group-based trajectory models using participants' Visual Analogue Scale (VAS) values of emotional state to calculate emotion differentiation, emotion variability, and emotion regulation at each time point and describe changes over time. Higher values for emotional variability indicate broader range of emotional fluctuations around an individual's mean. Emotion differentiation will be calculated by means of intraclass correlations, with high consistency across predefined episodes indicate poorer differentiation.

Number of steps taken by patients per day, as measured by an ambulatory, non-invasive activity-monitoring device worn around the wrist. Higher number of steps taken suggests more physical activity.