Long-Term Follow-Up of a Person-Centered Prehabilitation Program Based on Cognitive-Behavioral Physical Therapy for Patients Scheduled for Lumbar Fusion.

The initial power analysis did not account for between-group differences in the primary outcome at the 1- and 2-year follow-ups, potentially undermining the study's ability to detect meaningful differences at these later time points. Loss to follow-up occurred, with 46 intervention and 52 control participants remaining at 24 months, which may have further reduced statistical power. No power analyses were conducted for secondary outcomes, so non-significant results may be due to the study being underpowered to detect differences in these variables. The content of the conventional care was not strictly controlled, and physical therapists delivering it may have incorporated psychologically informed techniques, potentially making the control intervention more effective than anticipated. Minimal Important Change (MIC) was analyzed based on group means, which hides individual participants who may have achieved clinically relevant change. Causal conclusions about changes over time across groups are limited because there was no randomized wait-list control to distinguish the effects of surgery from the effects of the interventions.

The funders (Swedish Research Council, Eurospine Research, AFA Research) played no role in the design, conduct, and reporting of this study.

Do not conclude that prehabilitation is ineffective for all outcomes or that physical activity improvements are unnecessary. The study was underpowered for long-term secondary outcomes and showed that physical activity did not increase despite functional gains, suggesting a need for targeted activity interventions rather than dismissing the value of activity.