Strengths and Limitations
This study has some strengths. To our knowledge, it is the first randomized clinical trial evaluating the effect of PROM-based remote monitoring among patients receiving joint replacements. The randomized clinical trial design has several advantages, including randomization on the patient level, inclusion of multiple hospitals, and patient blinding, as well as the nonchangeability of group assignment via study nurses through the digital solution, and the large sample size. Moreover, the mixed-effects model accounts for several potential confounders. Because the intervention was not separated from routine care, the trial can give insights into the translation into routine practice.This study also has some limitations. The main limitation is the difficulty of isolating the intervention effect. We cannot determine which part of the intervention impacted the changes in health outcomes. Moreover, we cannot determine whether the differences were meaningful to patients or might have been partially explained through a learning effect. On the one hand, it would have been helpful to include earlier PROMs without alerts among the control group to evaluate whether a treatment effect before the 12-month mark could be observed. On the other hand, the control and intervention groups would have been more similar by both experiencing the monitoring step of the intervention. As in routine care, there might have been heterogeneity in the operationalization of the study design across hospitals. This possibility was addressed as much as possible via the study protocol, workshops, and regular check-ins with study nurses from all hospitals and controlling for the hospital in the mixed-effect model. Additionally, results might differ depending on the hospital implementing the intervention (eg, those with lower case volumes).