Harms, ancillary, and post-trial care
ADVERSE EVENTS
The adverse events were collected by weekly recording the number of adverse events throughout the intervention period. A closed-ended question with two options (yes or no) sent by the app at the end of each week: “During the last week of the study, did you present any different symptoms or worsening of the initial condition?”. Also, in case of a positive answer, a second closed question was asked: “Do you think this symptom or worsening of the initial condition was generated by the treatment provided in this study?”.At least two researchers discuss all adverse events: the main researcher (EFM), the study manager (CLA), and medical consultants and experts if necessary. If the treatment is causing the participant to deteriorate, a video call is offered with one of the study physiotherapists to evaluate the issue or suggest discontinuation of the treatment for the participant.In the case of the proven effectiveness of the exercises provided by the app in managing CLBP, access to the effective app version for participants in the control group after the end of the study period was provided.