A commentary on “Efficacy of a smartphone application assisting home-based rehabilitation and symptom management for patients with lung cancer undergoing video-assisted thoracoscopic lobectomy: a prospective, single-blinded, randomised control trial (POPPER study)”

Dear Editor, We read with great interest the report on the POPPER randomized controlled trial, which evaluated a smartphone-based application for home symptom management and rehabilitation following thoracoscopic lobectomy[1]. The authors proposed an innovative digital intervention integrating a symptom alert system, exercise modules, and educational content, demonstrating statistically significant improvements in pulmonary function recovery and patient-reported outcomes. We commend the investigators for their timely contribution to postoperative digital care; however, several methodological and interpretative issues merit further discussion. Although the difference in pulmonary function recovery rate (PFRR) between the app group and the standard care group reached statistical significance (79.32% vs. 75.73%; P = 0.04), the absolute improvement of approximately 3.6% may not translate into a clinically meaningful benefit. The study did not define the minimal clinically important difference for PFRR, nor did it report outcomes beyond 30 days. Given the natural recovery trajectory after thoracoscopic surgery, the short-term improvement observed may reflect an early motivational effect rather than sustained physiological gains. In addition, the single-blind design, in which clinicians and nurses were aware of group allocation, introduces potential performance bias. Participants in the app group received more frequent guidance, monitoring, and contact through the alert system, which may have enhanced adherence and engagement independently of the app’s intrinsic efficacy. Thus, the observed effects might largely represent an attention or engagement bias rather than the true functional value of the digital platform itself. The inclusion criteria limited enrollment to relatively healthy individuals (ECOG 0–1, capable of performing spirometry and exercise), restricting generalizability to older, frail, or less tech-savvy patients – who in fact constitute a substantial proportion of the post-lobectomy population. The mean age of 61 years and the very high satisfaction rate (95.5%) suggest participants had a good level of digital literacy, a feature that may not be easily replicated in real-world practice, where many elderly patients still face barriers to smartphone use. Furthermore, excluding patients with prolonged hospital stays or postoperative complications may underestimate the challenges of implementing this intervention in more complex recovery scenarios. The authors reported that participants who triggered alerts exhibited higher exercise intensity and greater pulmonary recovery. However, this finding may be confounded, as more motivated individuals are naturally inclined to report symptoms and adhere to exercise regimens more diligently. The causal direction between symptom monitoring and rehabilitation remains unclear, whether monitoring promotes recovery or recovery itself encourages more reporting. Without time-series analysis, attributing functional improvement directly to the alert mechanism remains speculative. Although no app-related adverse events were reported, the app group showed a numerically higher rate of emergency department visits (8.8% vs. 2.9%), which, despite lacking statistical significance, warrants attention. Heightened symptom awareness could lead to unnecessary consultations, reflecting potential hypersensitivity rather than improved self-management. Moreover, the study did not assess cost-effectiveness, caregiver burden, or healthcare resource utilization – key dimensions for evaluating digital health interventions. The recovery trajectory after pulmonary lobectomy typically extends beyond 1 month, with pulmonary function and quality of life continuing to improve over 3–6 months[2]. Without long-term follow-up data, it remains uncertain whether the observed benefits persist, plateau, or diminish once the intervention ceases. Extending follow-up with repeated assessments of lung function and quality of life would greatly enhance the clinical validity of the findings. In summary, the POPPER trial represents a valuable step toward digital-assisted postoperative rehabilitation in thoracic surgery. Nevertheless, its short-term effects, methodological limitations, and interpretive ambiguities temper the strength of its conclusions. Future research should incorporate clinically meaningful endpoints, ensure blinded assessment and balanced follow-up, include more diverse patient populations, and evaluate cost-effectiveness and long-term outcomes to establish the sustained value of such digital interventions. Consistent with the 2025 TITAN Guidelines[3], our review fully adheres to these guidelines.