scholarly journals Vial coring and fragmentation incidence after angled penetration of rubber stoppers with single-use hypodermic needles

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Marissa Rase ◽  
Mark Hanlon ◽  
Le Ho ◽  
Doug Duriez ◽  
Cathy Zhao
Keyword(s):  
Statistical Significance ◽  
Test Method ◽  
Data Sets ◽  
End User ◽  
Clinical Context ◽  
Needle Size ◽  
P Values ◽  
Insertion Angle ◽  
Patient Reported ◽  
Single Use

Abstract Objectives Particles due to fragmentation present a clear risk to the patient. Reported fragmentation rates vary, and an insertion angle at 45°, as opposed to 90°, has been proposed as a mitigation strategy. So, this study evaluated the fragmentation rates induced by single-use hypodermic needles using different angled penetration techniques. Methods Needles underwent fragmentation testing using two penetration techniques. In method 1, the needle was inserted through the stopper at 45° and rotated to 90° upon exiting the stopper underside, and in method 2 the needle was rotated only after the bevel was fully enveloped by the stopper. Methods were tested with 18, 20, and 22-gauge needles with bevel faced up, down, and sideways. Fragmentation data sets were subjected to ANOVA and a fit to a General Linear Model was attempted to ascertain the significance of needle size, bevel position, and penetration method; p-values less than 0.05 indicated statistical significance. Results Incidence varied from 0 to 49% and depended on the test method. Needles larger than 22-gauge induced fragmentation the most when the bevel was down. The bevel up position induced fragmentation the least. Generation of large fragments designated “cores” depended on all factors examined, and generation of small fragments designated “fragments” depended on all factors except for the penetration method. Conclusions Clinical context and intended application need to be communicated to manufacturers and considered for functional testing when devising end-user recommendations which must reflect a combination of factors.

scholarly journals RECAP reveals the true statistical significance of ChIP-seq peak calls

2018 ◽  
Author(s):  
Justin G. Chitpin ◽  
Aseel Awdeh ◽  
Theodore J. Perkins
Keyword(s):  
False Discovery Rate ◽  
Statistical Significance ◽  
Statistical Hypothesis ◽  
Data Sets ◽  
Peak Calling ◽  
Statistical Hypothesis Testing ◽  
P Values ◽  
False Discovery ◽  
Genomic Regions ◽  
And Control

AbstractMotivationChlP-seq is used extensively to identify sites of transcription factor binding or regions of epigenetic modifications to the genome. A key step in ChIP-seq analysis is peak calling, where genomic regions enriched for ChIP versus control reads are identified. Many programs have been designed to solve this task, but nearly all fall into the statistical trap of using the data twice—once to determine candidate enriched regions, and again to assess enrichment by classical statistical hypothesis testing. This double use of the data invalidates the statistical significance assigned to enriched regions, and as a consequence, invalidates false discovery rate estimates. Thus, the true significance or reliability of peak calls remains unknown.ResultsUsing simulated and real ChIP-seq data sets, we show that three well-known peak callers, MACS, SICER and diffReps, output optimistically biased p-values, and therefore optimistic false discovery rate estimates—in some cases, many orders of magnitude too optimistic. We propose a wrapper algorithm, RECAP, that uses resampling of ChIP-seq and control data to estimate and correct for biases built into peak calling algorithms. P-values recalibrated by RECAP are approximately uniformly distributed when applied to null hypothesis data, in which ChIP-seq and control come from the same genomic distributions. When applied to non-null data, RECAP p-values give a better estimate of the true statistical significance of candidate peaks and better false discovery rate estimates, which correlate better with empirical reproducibility. RECAP is a powerful new tool for assessing the true statistical significance of ChIP-seq peak calls.AvailabilityThe RECAP software is available on github at https://github.com/theodorejperkins/[email protected]

scholarly journals Do galactic bars depend on environment?: an information theoretic analysis of Galaxy Zoo 2

2020 ◽  
Vol 501 (1) ◽  
pp. 994-1001
Author(s):  
Suman Sarkar ◽  
Biswajit Pandey ◽  
Snehasish Bhattacharjee
Keyword(s):  
Spatial Distribution ◽  
Mutual Information ◽  
Local Density ◽  
Statistical Significance ◽  
Distribution Functions ◽  
Cumulative Distribution ◽  
Host Galaxy ◽  
Data Sets ◽  
Data Set ◽  
Information Theoretic

ABSTRACT We use an information theoretic framework to analyse data from the Galaxy Zoo 2 project and study if there are any statistically significant correlations between the presence of bars in spiral galaxies and their environment. We measure the mutual information between the barredness of galaxies and their environments in a volume limited sample (Mr ≤ −21) and compare it with the same in data sets where (i) the bar/unbar classifications are randomized and (ii) the spatial distribution of galaxies are shuffled on different length scales. We assess the statistical significance of the differences in the mutual information using a t-test and find that both randomization of morphological classifications and shuffling of spatial distribution do not alter the mutual information in a statistically significant way. The non-zero mutual information between the barredness and environment arises due to the finite and discrete nature of the data set that can be entirely explained by mock Poisson distributions. We also separately compare the cumulative distribution functions of the barred and unbarred galaxies as a function of their local density. Using a Kolmogorov–Smirnov test, we find that the null hypothesis cannot be rejected even at $75{{\ \rm per\ cent}}$ confidence level. Our analysis indicates that environments do not play a significant role in the formation of a bar, which is largely determined by the internal processes of the host galaxy.

Wilderness Medicine Education

2021 ◽  
Vol 9 (1) ◽  
pp. 49-55
Author(s):  
Seth C. Hawkins ◽  
Corey Winstead
Keyword(s):  
Continuing Education ◽  
First Aid ◽  
Program Director ◽  
End User ◽  
First Responder ◽  
Remote Areas ◽  
History Of ◽  
Single Use ◽  
Field Schools ◽  
Medicine Education

AbstractWilderness medicine classes are widely available to archaeologists and field scientists, but because wilderness medicine is an unregulated field, knowing what the various courses and products mean can be difficult. Based on the education chapter in the recently published textbook Wilderness EMS, this article—written by same two authors as the book—explores a number of topics relevant for the field scientist, program director, or administrator seeking to obtain wilderness medicine training for archaeologists. The article first explores the history of wilderness medicine products and certificates available to interested parties. It then differentiates between the various products available today along with their benefits and limitations for the end user. Products and trainings described include certifications (including Wilderness First Aid [WFA], Wilderness Advanced First Aid [WAFA], Advanced Wilderness First Aid [AWFA], and Wilderness First Responder [WFR]), as well as single use or continuing education trainings (including Stop the Bleed, CPR, conference courses, and field schools). Particular attention is paid to the specific and actionable needs of a field scientist in remote areas.

scholarly journals Cavalier Use of Inferential Statistics Is a Major Source of False and Irreproducible Scientific Findings

Mathematics ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 603
Author(s):  
Leonid Hanin
Keyword(s):  
Sample Size ◽  
Gaussian Approximation ◽  
Statistical Significance ◽  
Statistical Analyses ◽  
Random Sample Size ◽  
P Values ◽  
The Central Limit Theorem ◽  
Fixed Sample ◽  
Large Numbers ◽  
Significance Levels

I uncover previously underappreciated systematic sources of false and irreproducible results in natural, biomedical and social sciences that are rooted in statistical methodology. They include the inevitably occurring deviations from basic assumptions behind statistical analyses and the use of various approximations. I show through a number of examples that (a) arbitrarily small deviations from distributional homogeneity can lead to arbitrarily large deviations in the outcomes of statistical analyses; (b) samples of random size may violate the Law of Large Numbers and thus are generally unsuitable for conventional statistical inference; (c) the same is true, in particular, when random sample size and observations are stochastically dependent; and (d) the use of the Gaussian approximation based on the Central Limit Theorem has dramatic implications for p-values and statistical significance essentially making pursuit of small significance levels and p-values for a fixed sample size meaningless. The latter is proven rigorously in the case of one-sided Z test. This article could serve as a cautionary guidance to scientists and practitioners employing statistical methods in their work.

scholarly journals Psychosocial Telephone Counseling for Survivors of Cervical Cancer: Results of a Randomized Biobehavioral Trial

2015 ◽  
Vol 33 (10) ◽  
pp. 1171-1179 ◽  
Author(s):  
Lari Wenzel ◽  
Kathryn Osann ◽  
Susie Hsieh ◽  
Jo A. Tucker ◽  
Bradley J. Monk ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Repeated Measures ◽  
Statistical Significance ◽  
Multivariable Analysis ◽  
Telephone Counseling ◽  
Longitudinal Change ◽  
Categorical Variables ◽  
Patient Reported ◽  
Cytokine Levels ◽  
Cancer Experience

Purpose Survivors of cervical cancer experience quality-of-life (QOL) disruptions that persist years after treatment. This study examines the effect of a psychosocial telephone counseling (PTC) intervention on QOL domains and associations with biomarkers. Patients and Methods We conducted a randomized clinical trial in survivors of cervical cancer, who were ≥ 9 and less than 30 months from diagnosis (n = 204), to compare PTC to usual care (UC). PTC included five weekly sessions and a 1-month booster. Patient-reported outcomes (PROs) and biospecimens were collected at baseline and 4 and 9 months after enrollment. Changes in PROs over time and associations with longitudinal change in cytokines as categorical variables were analyzed using multivariable analysis of variance for repeated measures. Results Participant mean age was 43 years; 40% of women were Hispanic, and 51% were non-Hispanic white. Adjusting for age and baseline scores, participants receiving PTC had significantly improved depression and improved gynecologic and cancer-specific concerns at 4 months compared with UC participants (all P < .05); significant differences in gynecologic and cancer-specific concerns (P < .05) were sustained at 9 months. Longitudinal change in overall QOL and anxiety did not reach statistical significance. Participants with decreasing interleukin (IL) -4, IL-5, IL-10, and IL-13 had significantly greater improvement in QOL than those with increasing cytokine levels. Conclusion This trial confirms that PTC benefits mood and QOL cancer-specific and gynecologic concerns for a multiethnic underserved population of survivors of cancer. The improvement in PROs with decreases in T-helper type 2 and counter-regulatory cytokines supports a potential biobehavioral pathway relevant to cancer survivorship.

scholarly journals Intraperitoneal Microdialysis as a Monitoring Method in the Intensive Care Unit

2014 ◽  
Vol 99 (6) ◽  
pp. 729-733 ◽  
Author(s):  
Tasiopoulos Konstantinos ◽  
Komnos Apostolos ◽  
Paraforos Georgios ◽  
Tepetes Konstantinos
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Glucose Concentration ◽  
Repeated Measures ◽  
Statistical Significance ◽  
Monitoring Method ◽  
P Values ◽  
Repeated Measures Analysis ◽  
Low Glucose ◽  
Surgical Condition

Abstract Studies on surgical patients provide some evidence of prompt detection of enteric ischemia with microdialysis. The purpose of the study was to measure intraperitoneal microdialysis values (glucose, glycerol, pyruvate, and lactate) in patients hospitalized in an intensive care unit (ICU) with an underlying abdominal surgical condition and to correlate these values with patients' outcomes. Twenty-one patients, 10 female, were enrolled in the study. The intraperitoneal metabolite values were measured for 3 consecutive days, starting from the first day of ICU hospitalization. Descriptive and inferential statistics were performed. The t-test, repeated measures analysis, Holm's test, and a logistic regression model were applied. Level of statistical significance was set at P = 0.05. Mean age of participants was 68.10 ± 8.02 years old. Survivors exhibited statistically significantly higher glucose values on day 3 (6.61 ± 2.01 against 3.67 ± 1.62; P = 0.002). Mean lactate/ pyruvate (L/P) values were above 20 (35.35 ± 27.11). All non-survivors had a mean three day L/P values greater than 25.94. Low L/P values were related to increased survival possibilities. High microdialysis glucose concentration, high L/P ratio and low glucose concentration were the major findings during the first three ICU hospitalization days in non-survivors. Intraperitoneal microdialysis may serve as a useful tool in understanding enteric ischemia pathophysiology.

Comparing Midterm Outcomes of High-Level Athletes Versus Nonathletes Undergoing Primary Hip Arthroscopy: A Propensity-Matched Comparison With Minimum 5-Year Follow-up

2021 ◽  
pp. 036354652110417
Author(s):  
Andrew E. Jimenez ◽  
Peter F. Monahan ◽  
David R. Maldonado ◽  
Benjamin R. Saks ◽  
Hari K. Ankem ◽  
...  
Keyword(s):  
Hip Arthroscopy ◽  
Statistical Significance ◽  
Arthroscopic Surgery ◽  
Harris Hip Score ◽  
Control Group ◽  
Level Of Evidence ◽  
Femoroacetabular Impingement Syndrome ◽  
Patient Reported ◽  
High Level

Background: High-level athletes (HLAs) have been shown to have better short-term outcomes than nonathletes (NAs) after hip arthroscopy. Purpose: (1) To report midterm outcomes of HLAs after primary hip arthroscopy and (2) to compare their results with a propensity-matched cohort of NA patients. Study Design: Cohort study; Level of evidence, 3. Methods: Data were prospectively collected and retrospectively reviewed between February 2008 and November 2015 for HLAs (professional, college, or high school) who underwent primary hip arthroscopy in the setting of femoroacetabular impingement syndrome (FAIS). HLAs were included if they had preoperative, minimum 2-year, and minimum 5-year follow-up data for the modified Harris Hip Score (mHHS), Non-Arthritic Hip Score (NAHS), and Hip Outcome Score Sports-Specific Subscale (HOS-SSS). Radiographic and intraoperative findings, surgical procedures, patient-reported outcomes (PROs), patient acceptable symptomatic state (PASS), minimal clinically important difference (MCID), and return to sport were reported. The HLA study group was propensity-matched to a control group of NA patients for comparison. Results: A total 65 HLA patients (67 hips) were included in the final analysis with mean follow-up time of 74.6 ± 16.7 months. HLAs showed significant improvement in all PROs recorded, achieved high rates of MCID and PASS for mHHS (74.6% and 79.4%, respectively) and HOS-SSS (67.7% and 66.1%, respectively), and returned to sport at high rates (80.4%). When compared with the propensity-matched NA control group, HLAs reported higher baseline but comparable postoperative scores for the mHHS and NAHS. HLA patients achieved MCID and PASS for mHHS at similar rates as NA patients, but the HLA patients achieved PASS for HOS-SSS at higher rates that trended toward statistical significance (66.1% vs 48.4%; P = .07). NA patients underwent revision arthroscopic surgery at similar rates as HLA patients (14.9% vs 9.0%, respectively; P = .424). Conclusion: Primary hip arthroscopy results in favorable midterm outcomes in HLAs. When compared with a propensity-matched NA control group, HLAs demonstrated a tendency toward higher rates of achieving PASS for HOS-SSS but similar arthroscopic revision rates at minimum 5-year follow-up.

Abstract MP11: Circulating Plasma Biomarkers Associated With Brain Arteriovenous Malformations

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Sarah E Wetzel-Strong ◽  
Shantel M Weinsheimer ◽  
Jeffrey Nelson ◽  
Ludmila Pawlikowska ◽  
Dewi Clark ◽  
...  
Keyword(s):  
Multiple Testing ◽  
Statistical Significance ◽  
Protein Profiling ◽  
P Value ◽  
P Values ◽  
Plasma Biomarkers ◽  
Standard Curve ◽  
Disease States ◽  
Heparin Plasma ◽  
Circulating Levels

Objective: Circulating plasma protein profiling may aid in the identification of cerebrovascular disease signatures. This study aimed to identify circulating angiogenic and inflammatory biomarkers that may serve as biomarkers to differentiate sporadic brain arteriovenous malformation (bAVM) patients from other conditions with brain AVMs, including hereditary hemorrhagic telangiectasia (HHT) patients. Methods: The Quantibody Human Angiogenesis Array 1000 (Raybiotech) is an ELISA multiplex panel that was used to assess the levels of 60 proteins related to angiogenesis and inflammation in heparin plasma samples from 13 sporadic unruptured bAVM patients (69% male, mean age 51 years) and 37 patients with HHT (40% male, mean age 47 years, n=19 (51%) with bAVM). The Quantibody Q-Analyzer tool was used to calculate biomarker concentrations based on the standard curve for each marker and log-transformed marker levels were evaluated for associations between disease states using a multivariable interval regression model adjusted for age, sex, ethnicity and collection site. Statistical significance was based on Bonferroni correction for multiple testing of 60 biomarkers (P< 8.3x10 - 4 ). Results: Circulating levels of two plasma proteins differed significantly between sporadic bAVM and HHT patients: PDGF-BB (P=2.6x10 -4 , PI= 3.37, 95% CI:1.76-6.46) and CCL5 (P=6.0x10 -6 , PI=3.50, 95% CI=2.04-6.03). When considering markers with a nominal p-value of less than 0.01, MMP1 and angiostatin levels also differed between patients with sporadic bAVM and HHT. Markers with nominal p-values less than 0.05 when comparing sporadic brain AVM and HHT patients also included angiostatin, IL2, VEGF, GRO, CXCL16, ITAC, and TGFB3. Among HHT patients, the circulating levels of UPAR and IL6 were elevated in patients with documented bAVMs when considering markers with nominal p-values less than 0.05. Conclusions: This study identified differential expression of two promising plasma biomarkers that differentiate sporadic bAVMs from patients with HHT. Furthermore, this study allowed us to evaluate markers that are associated with the presence of bAVMs in HHT patients, which may offer insight into mechanisms underlying bAVM pathophysiology.

scholarly journals Children with 5′-end NF1 gene mutations are more likely to have glioma

2017 ◽  
Vol 3 (5) ◽  
pp. e192 ◽  
Author(s):  
Corina Anastasaki ◽  
Stephanie M. Morris ◽  
Feng Gao ◽  
David H. Gutmann
Keyword(s):  
Gene Mutation ◽  
Statistical Significance ◽  
Gene Mutations ◽  
Neurofibromatosis Type ◽  
Published Data ◽  
Data Sets ◽  
Nonsense Mutations ◽  
Data Set ◽  
Nf1 Gene ◽  
The Relationship

Objective:To ascertain the relationship between the germline NF1 gene mutation and glioma development in patients with neurofibromatosis type 1 (NF1).Methods:The relationship between the type and location of the germline NF1 mutation and the presence of a glioma was analyzed in 37 participants with NF1 from one institution (Washington University School of Medicine [WUSM]) with a clinical diagnosis of NF1. Odds ratios (ORs) were calculated using both unadjusted and weighted analyses of this data set in combination with 4 previously published data sets.Results:While no statistical significance was observed between the location and type of the NF1 mutation and glioma in the WUSM cohort, power calculations revealed that a sample size of 307 participants would be required to determine the predictive value of the position or type of the NF1 gene mutation. Combining our data set with 4 previously published data sets (n = 310), children with glioma were found to be more likely to harbor 5′-end gene mutations (OR = 2; p = 0.006). Moreover, while not clinically predictive due to insufficient sensitivity and specificity, this association with glioma was stronger for participants with 5′-end truncating (OR = 2.32; p = 0.005) or 5′-end nonsense (OR = 3.93; p = 0.005) mutations relative to those without glioma.Conclusions:Individuals with NF1 and glioma are more likely to harbor nonsense mutations in the 5′ end of the NF1 gene, suggesting that the NF1 mutation may be one predictive factor for glioma in this at-risk population.

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