Limitations of this study
An unexpected problem was the longer than expected time for patients on the surgical waiting list who had been allocated laparoscopic cholecystectomy. When designing the trial, it was anticipated that the waiting time would be, on average, six months. Therefore 18 months was chosen as the primary outcome follow-up time to reflect a time equivalent to 12 months after surgery. During the trial, however, we observed that patients often experienced longer waiting times for surgery, initially due to limited NHS resources, later compounded by the impact of covid-19 related restrictions. To address this, we added a 24 month follow-up point. Our sensitivity analyses on adherence to treatment suggested that the waiting list was unlikely to bias the study findings. The waiting list may, however, limit generalisability to some other countries’ jurisdictions. A further limitation was the non-blinding of participants and treating surgeons to allocation. In this trial, the pragmatic research question tested the most effective treatment strategy in a real life setting, leading to an inevitable lack of blinding. Finally, the cost effectiveness analysis was conducted from an NHS perspective, which may impact the generalisability of its results to other healthcare settings.