Methodology Score: 4.5/5
Usefulness Score: 4.5/5
Appelboam A, Reuben A, Mann C, et al.
Lancet. 2015 Aug 24. pii: S0140-6736(15)61485-4.
The REVERT trial, a pragmatic, multicenter RCT evaluating the efficacy of a modified Valsalva maneuver (supine positioning and passive leg elevation after Valsalva strain) vs standard Valsalva in patients with stable SVT, demonstrated a significantly increased success rate in converting patients back to sinus rhythm using the modified technique (43% vs 17%, absolute difference 26.2%, NNT 4). We should consider this modified method in our own ED patients with stable SVT since the treatment is simple, cost-effective, well tolerated, and has no risk of serious adverse events.
By: Dr. Tamara McColl
(Presented September 2015)
Concealment versus Blinding
These clinical trial terms have different meanings but are often confused. Concealment refers to the process whereby the treatment allocation is made unknown or concealed prior to patient randomization. This helps prevent selection bias by ensuring that health providers and research staff are not tempted to include or exclude cases according to their views on the allocated treatment. Blinding refers to the methods employed after randomization to ensure that patients, health care providers, and research staff cannot determine whether the patient is receiving the study or the control treatment. This reduces ascertainment bias (the likelihood of differential assessment of outcome).
By: Dr. Ian Stiell