HeadPoST: Rightly positioned, or flat out wrong?

ObjectiveTo critique the Head Positioning in Stroke Trial (HeadPoST) study methods in relation to preceding research findings in an aim to clarify the potential efficacy of positioning interventions and direction for future research.MethodsHead positioning research prior to the conduct of HeadPoST was reviewed by a team of international stroke experts, and methods and findings were compared to HeadPoST.ResultsMethods used to select HeadPoST patients differ substantially from those used in original head positioning studies, in particular enrollment of all types of stroke. HeadPoST enrolled primarily minor strokes (median NIH Stroke Scale 4, interquartile range [IQR] 2-8) without vascular imaging confirmation of subtype; elapsed time from stroke symptom onset to the initiation of intervention was late (median 14 hours, IQR 5-35), and time from hospital admission to enrollment was delayed (median 7 hours, IQR 2-26). Intervention integrity was not reported, including ability to achieve/maintain 30° head elevation in beds lacking head elevation capabilities. Deterioration or improvement associated with the intervention is unknown as serial assessments were not completed, and the trial's 3-month outcome was powered using unrelated study data.ConclusionsThe design of HeadPoST was suboptimal to measure differences produced by the intervention. Future head positioning trials in discrete patient cohorts (in particular, large vessel occlusion) with endpoints supported by pilot work are required to understand the efficacy of this simple yet potentially important intervention. © 2018 American Academy of Neurology

Acute Stroke Imaging Research Roadmap II.

The Stroke Imaging Research (STIR) Group, the American Society of Neuroradiology, and the Foundation of the American Society of Neuroradiology sponsored a series of working group meetings >12 months, with the final meeting occurring during the Stroke Treatment Academy Industry Roundtable (STAIR) on March 9 to 10, 2013, in Washington, DC. This process brought together vascular neurologists, neuroradiologists, neuroimaging research scientists, members of the National Institute of Neurological Disorders and Stroke, industry representatives, and members of the US Food and Drug Administration to discuss stroke imaging research priorities, especially in the light of the recent negative results of acute stroke clinical trials that tested the concept of penumbral imaging selection. The goal of this process was to propose a research roadmap for the next 5 years. STIR recommendations include (1) the use of standard terminology, aligned with the National Institute of Neurological Disorders and Stroke Common Data Elements. ; (2) a standardized imaging assessment of revascularization in acute ischemic stroke trials, including a modified Treatment In Cerebral Ischemia (mTICI) score. ; (3) a standardized process to assess whether ischemic core and penumbral imaging methods meet the requirements to be considered as an acceptable selection tool in acute ischemic stroke trials. ; (4) the characteristics of a clinical and imaging data repository to facilitate the development and testing process described in recommendation no. 3. ; (5) the optimal study design for a clinical trial to evaluate whether advanced imaging adds value in selecting acute ischemic stroke patients for revascularization therapy. ; (6) the structure of a stroke neuroimaging network to implement and coordinate the recommendations listed above. All of these recommendations pertain to research, not to clinical care

Knowledge-Based Jobs and the Boundaries of Firms Agent-based Simulation of Firms Learning and Workforce Skill Set Dynamics

The article explores emergence and survival of human resource management strategies and organisational types in a knowledge-based job market. The analysis considers a dynamic environment in which skill requirements change rapidly. We built an agent-based model to simulate a market where firms post job offers to fill vacancies and decide how to select and reward employees; employees, bearing skills, select firms comparing job offers. Taking an evolutionary approach, we explore how hiring strategies, which guarantee survival, emerge from interconnected variation, selection and retention processes. The simulation experiments suggest that, as the rate of change of the environment increases, long-term employment and firm-specific knowledge building emerge as the survival strategy