Minor head injury in anticoagulated patients: performance of biomarkers S100B, NSE, GFAP, UCH-L1 and Alinity TBI in the detection of intracranial injury. A prospective observational study.

OBJECTIVES: Data in literature indicate that in patients suffering a minor head injury (MHI), biomarkers serum levels could be effective to predict the absence of intracranial injury (ICI) on head CT scan. Use of these biomarkers in case of patients taking oral anticoagulants who experience MHI is very limited. We investigated biomarkers as predictors of ICI in anticoagulated patients managed in an ED. METHODS: We conducted a single-cohort, prospective, observational study in an ED. Our structured clinical pathway included a first head CT scan, 24 h observation and a second CT scan. The outcome was delayed ICI (dICI), defined as ICI on the second CT scan after a first negative CT scan. We assessed the sensitivity (SE), specificity (SP), negative predictive value (NNV) and positive predictive value (PPV) of the biomarkers S100B, NSE, GFAP, UCH-L1 and Alinity TBI in order to identify dICI. RESULTS: Our study population was of 234 patients with a negative first CT scan who underwent a second CT scan. The rate of dICI was 4.7 %. The NPV for the detection of dICI were respectively (IC 95 %): S100B 92.7 % (86.0-96.8 %,); ubiquitin C-terminal hydrolase-L1 (UCH-L1) 91.8 % (83.8-96.6 %); glial fibrillary protein (GFP) 100 % (83.2-100 %); TBI 100 % (66.4-100 %). The AUC for the detection of dICI was 0.407 for S100B, 0.563 for neuron-specific enolase (NSE), 0.510 for UCH-L1 and 0.720 for glial fibrillary acidic protein (GFAP), respectively. CONCLUSIONS: The NPV of the analyzed biomarkers were high and they potentially could limit the number of head CT scan for detecting dICI in anticoagulated patients suffering MHI. GFAP and Alinity TBI seem to be effective to rule out a dCI, but future trials are needed.

[Methodological problems associated with the planning of.]. / Problematiche metodologiche nella pianificazione e nel calcolo della dimensione del campione di un cluster randomized trial (CRT): il caso del Progetto Raffaello.

Cluster randomization, where groups (or clusters) of subjects, rather than single individuals, are randomly allocated to intervention groups, is increasingly being adopted in studies to evaluate interventions directed at a whole area or healthcare unit (such as a hospital ward, or a medical practice). Studies that use this method of randomization are referred to as cluster randomized trials (CRT) and have considerable organizational and economic advantages. However, CRTs have distinctive ethical issues that need to be considered and most importantly, require a series of methodological modifications during data analysis and calculation of sample size (during which additional parameters, such as the intracluster correlation coefficient and the design effect, need to be obtained). Methodological guidelines for conducting CRTs have been published in November 2002. However, no scientific articles dealing with the methodology associated with the design and analysis of this type of study have yet been published in Italian. The aim of this article, therefore, is to provide methodological support to healthcare researchers who are planning a CRT, through a description of the methodology used in the Raffaello project. This project is in the start-off phase in the Marche and Abruzzo regions of Italy and represents an excellent case study, it being a CRT aimed at evaluating the efficacy of a Disease Management model in the general population (with general practitioners therefore, being the cluster of randomization).