Discordance between Subjective and Objective Assessments of Activity after Pediatric Appendectomy

Background: Physical activity recovery after pediatric surgery can be assessed using objective measures such as step counts, but practice currently relies on subjective assessment by proxy. It is unclear how subjective and objective assessments of activity relate. We compared caregiver assessment of return to normal physical activity after pediatric appendectomy to step count recovery measured by a Fitbit. Methods: Pediatric patients who underwent appendectomy were recruited between 2020 and 2022 to be monitored for 21 d with a Fitbit. Patients were grouped by the postoperative day (POD) (7, 14, or 21) their caregiver first reported their activity was "back to normal." Objective return to normal step count was estimated for each group by modeling the inflection point from increasing steps to a plateau. These measures were determined discordant if the subjective report remained outside the modeled 95% confidence interval (CI) for the day the group plateaued. Results: Thirty-nine simple appendicitis and 40 complicated appendicitis patients were recruited. Among simple appendicitis patients, daily steps plateaued on POD 10.8 (95% CI 7.4-14.3), POD 14.0 (95% CI 11.0-17.1), and POD 11.1 (95% CI 6.9-15.3) for the day 7, day 14, and day 21 groups, respectively. Complicated appendicitis groups plateaued on POD 12.8 (95% CI 8.7-16.9), POD 15.2 (95% CI 11.1-19.3), and POD 16.7 (95% CI 12.3-21.0), respectively. the day 7 and day 14 simple groups and for the day 7 complicated group.