Tag: statistics

PLoS One. 2021 Jul 15;16(7):e0254538. doi: 10.1371/journal.pone.0254538. eCollection 2021.

ABSTRACT

AIM: The aim was to predict and understand variations in swimmer performance between individual and relay events, and develop a predictive model for the 4×200-m swimming freestyle relay event to help inform team selection and strategy.

DATA AND METHODS: Race data for 716 relay finals (4 x 200-m freestyle) from 14 international competitions between 2010-2018 were analysed. Individual 200-m freestyle season best time for the same year was located for each swimmer. Linear regression and machine learning was applied to 4 x 200-m swimming freestyle relay events.

RESULTS: Compared to the individual event, the lowest ranked swimmer in the team (-0.62 s, CI = [-0.94, -0.30]) and American swimmers (-0.48 s [-0.89, -0.08]) typically swam faster 200-m times in relay events. Random forest models predicted gold, silver, bronze and non-medal with 100%, up to 41%, up to 63%, and 93% sensitivity, respectively.

DISCUSSION: Team finishing position was strongly associated with the differential time to the fastest team (mean decrease in Gini (MDG) when this variable was omitted = 31.3), world rankings of team members (average ranking MDG of 18.9), and the order of swimmers (MDG = 6.9). Differential times are based on the sum of individual swimmer’s season’s best times, and along with world rankings, reflect team strength. In contrast, the order of swimmers reflects strategy. This type of analysis could assist coaches and support staff in selecting swimmers and team orders for relay events to enhance the likelihood of success.

PMID:34265006 | DOI:10.1371/journal.pone.0254538

PLoS One. 2021 Jul 15;16(7):e0254777. doi: 10.1371/journal.pone.0254777. eCollection 2021.

ABSTRACT

A growing trend in the caesarian section (CS) for delivery is a threat to child health as well as maternal health. This study was conducted to identify the potential socioeconomic and demographic factors associated with CS delivery in Bangladesh. Data obtained from the Bangladesh Demographic and Health Survey (BDHS) 2014 has been used for this study. The prevalence of CS delivery among Bangladeshi mothers was 24% (Urban: 36.9%, Rural: 17.9%). A two-level logistic regression showed that mothers having delivery in the private sector or private hospital (adjusted odds ratio [AOR] = 38.70, 95% confidence interval [CI] = 29.58 to 50.62), mother’s age 25-35 years (AOR = 1.73, 95% CI = 1.26 to 2.37), wealth index average (AOR = 1.61, 95% CI = 1.15 to 2.27) and rich (AOR = 1.80, 95% CI = 1.29 to 2.51), antenatal visit 1-2 (AOR = 2.31, 95% CI = 1.47 to 3.64) and ≥ 3 (AOR = 3.68, 95% CI = 2.35 to 5.76), overweight mothers (AOR = 1.44, 95% CI = 1.09 to 1.90), multiple births (AOR = 3.87, 95% CI = 1.15 to 12.58), husband’s occupation professional/technical/managerial (AOR = 1.68, 95% CI = 1.15 to 2.47) were significantly more prone to CS delivery. Also, place of residence, number of family members, birth order, child’s size during birth, and divisions of Bangladesh, were potentially associated with CS delivery. The current epidemiological findings and evidence suggest adopting and implementing some urgent clinical practices and strict guidelines in the healthcare system to avoid unnecessary CS delivery in Bangladesh.

PMID:34265013 | DOI:10.1371/journal.pone.0254777

PLoS One. 2021 Jul 15;16(7):e0254818. doi: 10.1371/journal.pone.0254818. eCollection 2021.

ABSTRACT

INTRODUCTION: Unsafe abortion is a leading cause of maternal mortality, and access to safe abortion services remains a public health priority in sub-Saharan Africa (SSA). A considerable amount of abortion research exists in the region; however, the spread of existing evidence is uneven such that some countries have an acute shortage of data with others over-researched. The imbalance reflects the complexities in prioritization among researchers, academics, and funders, and undeniably impedes effective policy and advocacy efforts. This scoping review aims to identify and map the landscape of abortion research in SSA, summarize existing knowledge, and pinpoint significant gaps, both substantive and geographic, requiring further investigation. This review will provide direction for future research, investments, and offer guidance for policy and programming on safe abortion.

MATERIALS AND METHODS: We utilize the Joanna Briggs Institute’s methodology for conducting scoping reviews. We will perform the search for articles in 8 electronic databases (i.e., PubMed, AJOL, Science Direct, SCOPUS, HINARI, Web of Knowledge, CINAHL, and WHO Regional Databases). We will include studies written in English or French language, produced or published between January 1, 2011, and July 31, 2021, and pertain directly to the subject of abortion in SSA. Using a tailored extraction frame, we will extract relevant information from publications that meet the inclusion criteria. Data will be analyzed using descriptive statistics and thematic analysis in response to key review questions.

ETHICS AND DISSEMINATION: Formal ethical approval is not required, as no primary data will be collected. The findings of this study will be disseminated through peer-reviewed publications and conference presentations.

PMID:34264992 | DOI:10.1371/journal.pone.0254818

PLoS One. 2021 Jul 15;16(7):e0254754. doi: 10.1371/journal.pone.0254754. eCollection 2021.

ABSTRACT

INTRODUCTION: Head injury, a common presentation to the emergency department (ED), is a substantial problem in developing countries like Nepal. The current national institute for health and clinical excellence (NICE) guideline revised in January 2014 focuses on effective clinical assessment and early management of head injuries according to their severity in all age groups. This study assessed the impact of implementing this guideline on the proportions of computed tomography (CT) head scans, guideline adherence, and confidence level of the attending physicians.

METHODS: We consecutively recruited 139 traumatic head injury (THI) patients in this prospective pre-post interventional study conducted in the ED of a tertiary care center. We implemented the NICE guideline into routine practice using multimodal intervention through physicians’ education sessions, information sheets and guideline-dissemination. The pre and post-implementation CT head scan rates were compared. The post-implementation guideline adherence was assessed. Online Google form-questionnaires including 12 validated case scenarios were distributed to the attending physicians at the end of both phases to assess their confidence levels.

RESULTS: The implementation resulted in a statistically significant decrease in the proportion of CT head scan rates from 92.0% to 70.0% (p-value = 0.005). Following educational interventions, improved guideline adherence of 20.3 percentage points (p-value = 0.001) was observed. Nine ED attending physicians were enrolled in the study who showed statistically significant improvement in their confidence level following the intervention. The NICE guideline showed a sensitivity and specificity of 93.6% and 76.4% with 82.6% accuracy compared to that of clinical judgment (100%, 34.6%, and 58.1% respectively) in detecting intracranial lesions.

CONCLUSION: The implementation was successful in satisfying the aim of the NICE guideline by decreasing the proportion of CT head scans, improving guideline adherence and increasing the confidence of the attending physicians.

PMID:34264993 | DOI:10.1371/journal.pone.0254754

PLoS One. 2021 Jul 15;16(7):e0253926. doi: 10.1371/journal.pone.0253926. eCollection 2021.

ABSTRACT

BACKGROUND: Mitochondrial dysfunction is involved in many complex diseases. Efficient and accurate evaluation of mitochondrial functionality is crucial for understanding pathology as well as facilitating novel therapeutic developments. As a popular platform, Seahorse extracellular flux (XF) analyzer is widely used for measuring mitochondrial oxygen consumption rate (OCR) in living cells. A hidden feature of Seahorse XF OCR data is that it has a complex data structure, caused by nesting and crossing between measurement cycles, wells and plates. Surprisingly, statistical analysis of Seahorse XF data has not received sufficient attention, and current methods completely ignore the complex data structure, impairing the robustness of statistical inference.

RESULTS: To rigorously incorporate the complex structure into data analysis, here we developed a Bayesian hierarchical modeling framework, OCRbayes, and demonstrated its applicability based on analysis of published data sets.

CONCLUSIONS: We showed that OCRbayes can analyze Seahorse XF OCR experimental data derived from either single or multiple plates. Moreover, OCRbayes has potential to be used for diagnosing patients with mitochondrial diseases.

PMID:34265000 | DOI:10.1371/journal.pone.0253926

PLoS One. 2021 Jul 15;16(7):e0254366. doi: 10.1371/journal.pone.0254366. eCollection 2021.

ABSTRACT

BACKGROUND: To develop a clinical prediction model to identify children at risk for revisits with serious illness to the emergency department.

METHODS AND FINDINGS: A secondary analysis of a prospective multicentre observational study in five European EDs (the TRIAGE study), including consecutive children aged <16 years who were discharged following their initial ED visit (‘index’ visit), in 2012-2015. Standardised data on patient characteristics, Manchester Triage System urgency classification, vital signs, clinical interventions and procedures were collected. The outcome measure was serious illness defined as hospital admission or PICU admission or death in ED after an unplanned revisit within 7 days of the index visit. Prediction models were developed using multivariable logistic regression using characteristics of the index visit to predict the likelihood of a revisit with a serious illness. The clinical model included day and time of presentation, season, age, gender, presenting problem, triage urgency, and vital signs. An extended model added laboratory investigations, imaging, and intravenous medications. Cross validation between the five sites was performed, and discrimination and calibration were assessed using random effects models. A digital calculator was constructed for clinical implementation. 7,891 children out of 98,561 children had a revisit to the ED (8.0%), of whom 1,026 children (1.0%) returned to the ED with a serious illness. Rates of revisits with serious illness varied between the hospitals (range 0.7-2.2%). The clinical model had a summary Area under the operating curve (AUC) of 0.70 (95% CI 0.65-0.74) and summary calibration slope of 0.83 (95% CI 0.67-0.99). 4,433 children (5%) had a risk of > = 3%, which was useful for ruling in a revisit with serious illness, with positive likelihood ratio 4.41 (95% CI 3.87-5.01) and specificity 0.96 (95% CI 0.95-0.96). 37,546 (39%) had a risk <0.5%, which was useful for ruling out a revisit with serious illness (negative likelihood ratio 0.30 (95% CI 0.25-0.35), sensitivity 0.88 (95% CI 0.86-0.90)). The extended model had an improved summary AUC of 0.71 (95% CI 0.68-0.75) and summary calibration slope of 0.84 (95% CI 0.71-0.97). As study limitations, variables on ethnicity and social deprivation could not be included, and only return visits to the original hospital and not to those of surrounding hospitals were recorded.

CONCLUSION: We developed a prediction model and a digital calculator which can aid physicians identifying those children at highest and lowest risks for developing a serious illness after initial discharge from the ED, allowing for more targeted safety netting advice and follow-up.

PMID:34264983 | DOI:10.1371/journal.pone.0254366

PLoS One. 2021 Jul 15;16(7):e0254413. doi: 10.1371/journal.pone.0254413. eCollection 2021.

ABSTRACT

The best agro-industrial performance presented by a crop genotype in one environment may not be reproduced in another owing to complex edaphoclimatic variations. Therefore, breeding programs are constantly attempting to obtain, through artificial hybridization, novel genotypes with high adaptability and stability potential. The objective of this study was to analyze genetic divergence in sugarcane based on the genotypic values of adaptability and stability. A total of 11 sugarcane genotypes were analyzed for eight agro-industrial traits. The genotypic values of the traits were determined using mixed model methodology, and the genetic divergence based on phenotypic and genotypic values was measured using the Mahalanobis distance. The distance matrices were correlated using the Mantel test, and the genotypes were grouped using the Tocher method. Genetic divergence is more accurate when based on genotypic values free of genotype-environment interactions and will differ from genetic divergence based on phenotypic data, changing the genotype allocations in the groups. The above methodology can be applied to assess genetic divergence to obtain novel sugarcane genotypes with higher productivity that are adapted to intensive agricultural systems using diverse technologies. This methodology can also be tested in other crops to increase accuracy in selecting the parents to be crossed.

PMID:34264990 | DOI:10.1371/journal.pone.0254413

PLoS One. 2021 Jul 15;16(7):e0254343. doi: 10.1371/journal.pone.0254343. eCollection 2021.

ABSTRACT

This study aimed to assess the value of quick sequential organ failure assessment (qSOFA) combined with other risk factors in predicting in-hospital mortality in patients presenting to the emergency department with suspected infection. This post-hoc analysis of a prospective multicenter study dataset included 34 emergency departments across Japan (December 2017 to February 2018). We included adult patients (age ≥16 years) who presented to the emergency department with suspected infection. qSOFA was calculated and recorded by senior emergency physicians when they suspected an infection. Different types of sepsis-related risk factors (demographic, functional, and laboratory values) were chosen from prior studies. A logistic regression model was used to assess the predictive value of qSOFA for in-hospital mortality in models based on the following combination of predictors: 1) qSOFA-Only; 2) qSOFA+Age; 3) qSOFA+Clinical Frailty Scale (CFS); 4) qSOFA+Charlson Comorbidity Index (CCI); 5) qSOFA+lactate levels; 6) qSOFA+Age+CCI+CFS+lactate levels. We calculated the area under the receiver operating characteristic curve (AUC) and other key clinical statistics at Youden’s index, where the sum of sensitivity and specificity is maximized. Following prior literature, an AUC >0.9 was deemed to indicate high accuracy; 0.7-0.9, moderate accuracy; 0.5-0.7, low accuracy; and 0.5, a chance result. Of the 951 patients included in the analysis, 151 (15.9%) died during hospitalization. The AUC for predicting in-hospital mortality was 0.627 (95% confidence interval [CI]: 0.580-0.673) for the qSOFA-Only model. Addition of other variables only marginally improved the model’s AUC; the model that included all potentially relevant variables yielded an AUC of only 0.730 (95% CI: 0.687-0.774). Other key statistic values were similar among all models, with sensitivity and specificity of 0.55-0.65 and 0.60-0.75, respectively. In this post-hoc data analysis from a prospective multicenter study based in Japan, combining qSOFA with other sepsis-related risk factors only marginally improved the model’s predictive value.

PMID:34264977 | DOI:10.1371/journal.pone.0254343

J Magn Reson Imaging. 2021 Jul 15. doi: 10.1002/jmri.27823. Online ahead of print.

ABSTRACT

BACKGROUND: Although perfusion imaging plays a key role in the management of steno-occlusive diseases, the clinical usefulness of arterial spin labeling (ASL) is limited by technical issues.

PURPOSE: To examine the effect of arterial transit time (ATT) prolongation on cerebral blood flow (CBF) measurement accuracy and identify the best CBF measurement protocol for steno-occlusive diseases.

STUDY TYPE: Prospective.

POPULATION: Moyamoya (n = 10) and atherosclerotic diseases (n = 8).

FIELD STRENGTH/SEQUENCE: A 3.0T/3DT₁ -weighted and ASL.

ASSESSMENT: Hadamard-encoded multidelay ASL scans with/without vessel suppression (VS) and single-delay ASL scans with long-label duration (LD) and long postlabeling delay (PLD), referred to as long-label long-delay (LLLD), were acquired. CBF measurement accuracy and its ATT dependency, measured as the correlation between the relative CBF measurement difference (ASL-single-photon emission computed tomography [SPECT]) and ATT, were compared among 1) Combo (incorporating multidelay and LLLD data based on ATT), 2) standard (LD/PLD = 1333/2333 msec), and 3) LLLD (LD/PLD = 4000/4000 msec) protocols, using whole-brain voxel-wise correlation with reference standard SPECT CBF. The effect of VS on CBF measurement accuracy was also assessed.

STATISTICAL TESTS: Pearson’s correlation coefficient, repeated-measures analysis of variance, t-test. P< 0.05 was considered significant.

RESULTS: Pearson’s correlation coefficients between ASL and SPECT CBF measurements were as follows: Combo = 0.55 ± 0.09; standard = 0.52 ± 0.12; LLLD = 0.41 ± 0.10. CBF measurement was least accurate in LLLD and most accurate in Combo. VS significantly improved overall CBF measurement accuracy in the standard protocol and in moyamoya patients for the Combo. ATT dependency analysis revealed that, compared with Combo, the standard and LLLD protocols showed significantly lower and negative and significantly higher and positive correlations, respectively (standard = -0.12 ± 0.04, Combo = -0.04 ± 0.03, LLLD = 0.17 ± 0.03).

DATA CONCLUSION: By using ATT-corrected CBF derived from LD/PLD = 1333/2333 msec as a base and by compensating underestimation in delayed regions using multidelay scans, the ATT-based Combo strategy improves CBF measurement accuracy compared with single-delay protocols in severe steno-occlusive diseases.

EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.

PMID:34263988 | DOI:10.1002/jmri.27823

Minerva Dent Oral Sci. 2021 Jul 15. doi: 10.23736/S2724-6329.21.04523-X. Online ahead of print.

ABSTRACT

AIM: The purpose of this research was to evaluate the dentinal microcracks formation after root canal preparation with Hyflex EDM (Electrical Discharge Machining), Neolix Neoniti A1 EDM, Wave One Gold and Edge File X1 under illumination and magnification.

MATERIALS AND METHODS: 150 mandibular molars with 2 different mesial canals extracted for periodontal reasons were included in the study. The samples were decoronated at 15mm from the apex using a carborundum disc under copious water cooling. Access opening was done using a round bur. Sectioning of the distal root was done. Patency of mesial canals were checked using a 10K file. The samples were randomly divided into 5 groups using simple randomization technique. Group 1: Uninstrumented group. Group 2: Hyflex EDM(HEDM). Group 3: Neolix Neoniti A1(NA1). Group 4: Wave One Gold (WOG). Group 5: Edge File X1(EFX). Biomechanical preparation in all groups was done following the manufacturer’s instructions. Sectioning was done at 3mm, 6mm, and 9mm from the apex using a 0.13mm circular saw under copious water cooling. Sections were observed at 16x magnification under the dental operating microscope and illumination using a Light Emitting Diode (LED) curing light. The chi-square test was used to determine the statistically significant differences at P < .05. Intergroup comparison was done by the Post hoc Tukey test.

RESULTS: Total of 1800 images were analyzed. The highest number of cracks was seen in Neoniti A1 group (43.33%) while the least number of cracks were seen with Wave One Gold group (13.33%). There was statistically difference between reciprocating groups and the rotary group.

CONCLUSIONS: Within the limitations of this study, it can be concluded that all the heat-treated file systems produced dentinal microcracks. Rotary group(NA1 and HEDM) produced significantly more cracks than Reciprocation group (WOG and EFX).

PMID:34264044 | DOI:10.23736/S2724-6329.21.04523-X