Editor

We welcome Spence and colleagues' comments on the LaCeS randomised controlled feasibility trial1. The LaCeS feasibility trial was designed as an external feasibility trial to assess our ability to recruit patients and implement key trial processes in the emergency colorectal setting whilst delivering definitive surgical care. The results informed the design of our NIHR HTA funded (Ref NIHR128815) definitive, phase III trial LaCeS2, which will assess the effectiveness and cost-effectiveness of emergency laparoscopic colorectal surgery.

LaCeS was designed with an embedded qualitative study using in depth, one to one qualitative interviews (separate manuscript in preparation). The aim was to explore patient and clinician acceptability of trial processes, including recruitment, randomisation and follow up. A purposive sampling strategy was employed to ensure all key patient and healthcare professionals demographics were captured. All patients approached to participate in the trial were invited to participate in an interview irrespective of patient consent or dissent to the trial. Principle investigators and recruiters from all sites participated in qualitative interviews. All qualitative data was analysed using the principles of thematic analysis2 with data collection and analysis running in parallel to the point data saturation was reached.

The challenges of blinding in surgical trials have been widely acknowledged, with potential difficulties in blinding both patients and surgeons3. Blinding outcome assessors is a recognised strategy employed in surgical trials to reduce bias, however, in practice is only used in a quarter of surgical trials4. Given the complexity of conducting an emergency surgery trial and the early reporting of patient-reported outcomes a pragmatic decision was made to design the trial as a single-blinded trial with blinding of patients alone. There is some emerging evidence that there is no difference in estimated treatment effects between trials with and without blinded patients, healthcare providers, or outcome assessors, suggesting blinding is not as methodologically important as previously assumed5.