Strengths and weaknesses of the study
AWD
SECONDARY, CONTRACTIONS
Our trial has several limitations. First, the AWD that was used as the primary outcome measure showed a large range in both groups at baseline, with a right-skewed distribution. We did not stratify by baseline AWD for the primary outcome analysis. Second, only 160 participants had analysable primary outcome data due to missing treadmill data at baseline and/or 3 months. The number of participants lost to follow-up was higher than first anticipated. Additionally, the COVID-19 pandemic resulted in local centre policy, at some participating centres, dictating that participants were not permitted to attend study appointments face to face. Instead, remote visits were performed with physical assessments, such as the treadmill test, being missed. Certain secondary outcomes, such as haemodynamic measures, were not adjusted for centre effects and thus may not account for centre–centre variability. Finally, there was the absence of a sham device comparator. This was considered during the protocol design but was deemed impractical to implement due to the patient setting the stimulation level to a threshold where calf contractions are visible (the IsoRocker feature allows the device to tilt back and forth).The main strength of the NESIC trial is that this is the first moderately sized RCT looking at the adjuvant benefit of NMES in patients with IC. The results of this trial are generalizable across vascular units that provide SET and those that provide BMT only. A further strength is that compliance data were collected separately for NMES, SET and exercise advice, with clear definitions on what is deemed as compliant.