Neuromuscular Electrical Stimulation Improves Activities of Daily Living Post Stroke: A Systematic Review and Meta-analysis.

Mean PEDro score was 5.8 out of 10, which the authors rate as fair quality. None of the 20 trials used blinded therapists, and only 2 blinded participants, so performance bias is a real concern. The protocol was not preregistered, which the authors acknowledge introduces the possibility of reporting bias. The search was limited to English-language publications and no grey literature was included. No trials included patients with mild paresis, and very few covered the acute (first week) or chronic (beyond 6 months) stages, so the findings cannot be generalised to those populations. Stimulation parameters varied widely across trials (frequency, pulse width, session duration, number of channels), and no two studies used the same protocol, making it hard to identify what specifically produced the effect. The intervention group received NMES outside formal therapy sessions, adding extra therapy time. The authors themselves note that time in therapy is a known predictor of recovery and that this may account for part of the ADL benefit. The motor ability subgroup for severe paresis included only 4 studies, and the authors caution that half the studies were excluded from that subgroup due to poor data reporting.

Do not read the ADL improvement as evidence that NMES improves motor strength or movement quality. The motor ability outcome was not significant (P = .30), and the ADL benefit may partly reflect the extra therapy time the stimulation group received outside formal sessions rather than the electrical stimulation itself.