This report presents the Consolidated Standards of Reporting Trials (CONSORT) extension for the stepped wedge cluster randomised trial (SW-CRT). The SW-CRT involves randomisation of clusters to different sequences that dictate the order (or timing) at which each cluster will switch to the intervention condition. The statement was developed to allow for the unique characteristics of this increasingly used study design. The guideline was developed using a Delphi survey and consensus meeting; and is informed by the CONSORT statements for individual and cluster randomised trials. Reporting items along with explanations and examples are provided. We include a glossary of terms, and explore the key properties of the SW-CRT which require special consideration in their reporting.

Summary At present in the UK there is no consensus regarding the parameters anaesthetists use to indicate adequacy of reversal from neuromuscular blockade. In an attempt to determine current practice, we carried out a survey covering 12 anaesthetic departments throughout the UK. Individuals were asked to give details regarding their usage of available monitors or, alternatively, to list those clinical parameters which they felt offered the best guidance as to the adequacy of recovery from neuromuscular blockade. There was no consensus among anaesthetists as to the most reliable clinical signs of recovery from neuromuscular blockade. There was an apparent lack of understanding of the limitations of some clinical signs used to determine recovery, as well as inappropriate application of others. In all departments where monitors (quantitative or qualitative) were available, there was limited knowledge regarding the current minimum recommended train‐of‐four ratio which should be observed prior to extubation. There is an apparent overall confusion among clinicians as to the best method to confirm recovery from neuromuscular blockade. This is probably due to the lack of a single reliable clinical test which can be applied in the immediate postoperative period. Insufficient reliance is placed upon the use of quantitative monitors. There is a lack of clarity in national anaesthetic guidelines with respect to monitoring of neuromuscular function. Current standards need to be re‐assessed in the light of recent improvements in nerve stimulators.

BackgroundThe stepped wedge (SW) cluster randomized controlled trial (CRCT) design is being used with increasing frequency. However, there is limited published research on the quality of reporting of SW-CRCTs. We address this issue by conducting a literature review.MethodsMedline, Ovid, Web of Knowledge, the Cochrane Library, PsycINFO, the ISRCTN registry, and ClinicalTrials.gov were searched to identify investigations employing the SW-CRCT design up to February 2015. For each included completed study, information was extracted on a selection of criteria, based on the CONSORT extension to CRCTs, to assess the quality of reporting.ResultsA total of 123 studies were included in our review, of which 39 were completed trial reports. The standard of reporting of SW-CRCTs varied in quality. The percentage of trials reporting each criterion varied to as low as 15.4%, with a median of 66.7%.ConclusionsThere is much room for improvement in the quality of reporting of SW-CRCTs. This is consistent with recent findings for CRCTs. A CONSORT extension for SW-CRCTs is warranted to standardize the reporting of SW-CRCTs.Electronic supplementary materialThe online version of this article (doi:10.1186/s13063-017-1783-0) contains supplementary material, which is available to authorized users.

Sample size derivation is a crucial element of planning any confirmatory trial. The required sample size is typically derived based on constraints on the maximal acceptable Type I error rate and minimal desired power. Power depends on the unknown true effect and tends to be calculated either for the smallest relevant effect or a likely point alternative. The former might be problematic if the minimal relevant effect is close to the null, thus requiring an excessively large sample size, while the latter is dubious since it does not account for the a priori uncertainty about the likely alternative effect. A Bayesian perspective on sample size derivation for a frequentist trial can reconcile arguments about the relative a priori plausibility of alternative effects with ideas based on the relevance of effect sizes. Many suggestions as to how such "hybrid" approaches could be implemented in practice have been put forward. However, key quantities are often defined in subtly different ways in the literature. Starting from the traditional entirely frequentist approach to sample size derivation, we derive consistent definitions for the most commonly used hybrid quantities and highlight connections, before discussing and demonstrating their use in sample size derivation for clinical trials.

M ethylene blue inhibits the enzyme guanylate cyclase, avoiding the cyclic guanosine 3Ј5Ј-monophosphate (cGMP)-dependent vasorelaxant effects of nitric oxide in the smooth muscle of vessels. As well as its uses in the treatment of methemoglobinemia and malaria and as a medical dye, methylene blue has been used to treat refractory vasoplegia after cardiopulmonary bypass (CPB), anaphylaxis, and septic shock. 1,2 We describe the first case of methylene blue used in the CPB prime and in the context of refractory hypotension in a patient undergoing valve replacement surgery for infective endocarditis.