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Journal of Applied Statistics 2022Functional box plots satisfy two needs; visualization of functional data, and the calculation of important box plot statistics. Data visualization illuminates key...
Functional box plots satisfy two needs; visualization of functional data, and the calculation of important box plot statistics. Data visualization illuminates key characteristics of functional sets missed by statistical tests and summary statistics. The calculation of box plot statistics for functional sets permits a novel comparison more suited to functional data. The functional box plot uses a depth method to visualize and rank smooth functional curves in terms of a mean, box, whiskers, and outliers. The functional box plot improves upon other classic functional data analysis tools such as functional principal components and discriminant analysis for outlier detection. This research adds wavelet analysis as a generating mechanism along with depth for functional box plots to visualize functional data and calculate relevant statistics. The wavelet analysis of variance box plot tool gives competitive error rates in Gaussian test cases with magnitude outliers, and outperforms the functional box plot, for Gaussian test cases with shape outliers. Further, we show wavelet analysis is well suited at approximating irregular and noisy functional data and show the enhanced capability of WANOVA box plots to classify shape outliers which follow a different pattern than other functional data for both simulated and real data instances.
PubMed: 36246858
DOI: 10.1080/02664763.2021.1951685 -
EFORT Open Reviews Jan 2023Recent concerns surrounding joint replacements that have a higher than expected rate of revision have led to stricter controls by regulatory authorities with regards to... (Review)
Review
Recent concerns surrounding joint replacements that have a higher than expected rate of revision have led to stricter controls by regulatory authorities with regards to the introduction of new devices into the marketplace. Implant post-market surveillance remains important, and joint replacement registries are ideally placed to perform this role. This review examined if and how joint replacement registries identified outlier prostheses, outlined problems and suggested solutions to improve post-market surveillance. A search was performed of all joint replacement registries that had electronic or published reports detailing the outcomes of joint replacement. These reports were examined for registry identification of outlier prostheses. Five registries publicly identified outlier prostheses in their reports and the methods by which this was performed, and three others had internal reports. Identification of outlier prostheses is one area that may improve overall joint replacement outcomes; however, further research is needed to determine the optimum methods for identification, including the threshold, the comparator and the numbers required for notification of devices. Co-operation of registries at a global level may lead to earlier identification of devices and thereby further improve the results of joint replacement.
PubMed: 36705620
DOI: 10.1530/EOR-22-0058 -
Brain and Behavior Nov 2023Patients with autism spectrum disorder (ASD) commonly experience aberrant skin sensation sensitivity; however, the causal relationship is not yet clear. This study uses...
BACKGROUND AND AIM
Patients with autism spectrum disorder (ASD) commonly experience aberrant skin sensation sensitivity; however, the causal relationship is not yet clear. This study uses a bidirectional Mendelian randomization (MR) method to explore the relationship between disturbance of skin sensation (DSS) and ASD.
METHODS
Single-nucleotide polymorphisms (SNPs) extracted from the summary data of genome-wide association studies were used as genetic instruments. MR was performed using the inverse-variance-weighted method, with alternate methods (e.g., weighted median, MR-Egger, simple mode, weighted mode, and MR-pleiotropy residual sum and outlier) and multiple sensitivity analyses to assess horizontal pleiotropy and remove outliers.
RESULTS
The results of the analysis using six SNPs as genetic instruments showed that the DSS is associated with an increased risk of ASD (odds ratio = 1.126, 95% confidence interval = 1.029-1.132; p = .010). The results of the sensitivity analyses were robust with no evidence of pleiotropy. The reverse MR analyses showed no causal effects of ASD on DSS.
CONCLUSION
This study's findings suggest that DSS has potential causal effects on ASD, whereas ASD has no effect on DSS. Thus, skin sensitivity may represent a behavioral marker of ASD, by which some populations could be subtyped in the future.
Topics: Humans; Autism Spectrum Disorder; Genome-Wide Association Study; Mendelian Randomization Analysis; Skin; Sensation
PubMed: 37670485
DOI: 10.1002/brb3.3238 -
The Laryngoscope Jul 2022Balloon sinuplasty (BSP) is associated with varied practice patterns. This study sought to identify otolaryngologist characteristics associated with BSP utilization.
OBJECTIVE
Balloon sinuplasty (BSP) is associated with varied practice patterns. This study sought to identify otolaryngologist characteristics associated with BSP utilization.
STUDY DESIGN
Retrospective analysis of Medicare claims data and the National Physician Compare database.
METHODS
Outlier otolaryngologists were compared to non-outliers. Otolaryngologist characteristics included sex, practice size, geographic setting, years of experience, procedure setting, 10 or fewer endoscopic sinus surgeries per year for 3 or more years, and high number of services per unique Medicare beneficiary. Outlier status was defined as performing an annual total of balloon procedures of 2 standard deviations (SDs) above the mean for all otolaryngologists in the same year.
RESULTS
Between January 2012 and December 2017, 1,408 otolaryngologists performed 101,662 endoscopic sinus surgeries and 97,680 BSP procedures. Sixty-six outlier otolaryngologists (4.7%) accounted for 44.3% of all BSP procedures. Outlier status was associated with practice size of 10 or fewer individual providers (OR, 5.15; 95% CI, 2.73-9.74; P < .001), performance of 10 or fewer total endoscopic sinus surgeries per year for 3 or more years (OR, 3.90; 95% CI, 1.59-9.57; P = .003), and high number of overall services per beneficiary (OR 6.70; 95% CI, 1.19-37.84; P = .031). Provider sex, years of experience, and geographic setting were not associated with outlier status.
CONCLUSION
Outlier BSP patterns are associated with a few otolaryngologists who are more likely to be identified in small practices and record low numbers of endoscopic surgeries. Although BSP is an appropriate and effective tool, identification of outlier patterns may help to facilitate peer-to-peer counsel.
LEVEL OF EVIDENCE
3 Laryngoscope, 132:1340-1345, 2022.
Topics: Aged; Endoscopy; Humans; Medicare; Otolaryngologists; Paranasal Sinuses; Practice Patterns, Physicians'; Retrospective Studies; United States
PubMed: 34405899
DOI: 10.1002/lary.29824 -
Brain and Behavior Mar 2024Despite numerous investigations into the relationship between physical activities (PA) and epilepsy, the causal effects remain contentious. Thus, we conducted a...
BACKGROUND
Despite numerous investigations into the relationship between physical activities (PA) and epilepsy, the causal effects remain contentious. Thus, we conducted a two-sample Mendelian randomization (MR) study to assess the potential causality.
METHODS
Single-nucleotide polymorphisms (SNPs) predisposed to self-reported moderate and vigorous physical activities (MPA and VPA) and overall acceleration average (OAA) calculated through wrist-worn accelerometers were selected as exposure instrumental variables. Five subtypes of epilepsy, including all epilepsy, focal epilepsy and generalized epilepsy (with or without each other), focal epilepsy-strict definition and generalized epilepsy-strict definition (without overlap), were chosen as the outcomes. The MR study utilized the inverse-variance weighted (IVW) method as the primary analytical tool, supplemented by MR-Egger, simple mode, weighted mode, and weighted median methods. Cochran's Q and MR-Egger intercept tests were employed to assess heterogeneity and pleiotropy, while MR pleiotropy residual sum and outlier and leave-one-out analyses were conducted to identify potential SNP outliers.
RESULTS
The study indicated that OAA was genetically linked to a decreased risk of both focal epilepsy (OR = 0.812, 95% CI: 0.687-0.960, p = .015, IVW) and focal epilepsy-strict definition (OR = 0.732, 95% CI: 0.596-0.900, p = .003, IVW; OR = 0.749, 95% CI: 0.573-0.979, p = .035, Weighted median). Genetically predicted MPA and VPA did not exhibit a causal association with all epilepsy or its subtypes (p>.05). No evidence of heterogeneity, pleiotropy, or SNP outlier was observed.
CONCLUSIONS
Our findings suggested that PA with accelerometer monitoring may potentially reduce the risk of focal epilepsy, while there is no evidence supporting causal association between self-reported MPA or VPA and either focal or generalized epilepsy.
Topics: Humans; Mendelian Randomization Analysis; Epilepsy; Epilepsies, Partial; Epilepsy, Generalized; Exercise
PubMed: 38451009
DOI: 10.1002/brb3.3463 -
Scientific Reports Mar 2023There is still some controversy about the relationship between lipids and venous thrombosis (VTE). A bidirectional Mendelian randomization (MR) study was conducted to... (Randomized Controlled Trial)
Randomized Controlled Trial
There is still some controversy about the relationship between lipids and venous thrombosis (VTE). A bidirectional Mendelian randomization (MR) study was conducted to clarify the causal relationship between three classical lipids (low-density lipoprotein (LDL), high-density lipoprotein (HDL) and triglycerides (TGs)) and venous thromboembolism (VTE) (deep venous thrombosis (DVT) and pulmonary embolism (PE)). Three classical lipids and VTE were analysed by bidirectional Mendelian randomization (MR). We used the random effect inverse variance weighted (IVW) model as the main analysis model and the weighted median method, simple mode method, weighted mode method and MR-Egger methods as supplementary methods. The leave-one-out test was used to determine the influence of outliers. The heterogeneity was calculated by using Cochran Q statistics in the MR-Egger and IVW methods. The intercept term in the MR‒Egger regression was used to indicate whether horizontal pleiotropy affected the results of the MR analysis. In addition, MR-PRESSO identified outlier single-nucleotide polymorphisms (SNPs) and obtained a stable result by removing outlier SNPs and then performing MR analysis. When we used three classical lipids (LDL, HDL and TGs) as exposure variables, no causal relationship between them and VTE (DVT and PE) was found. In addition, we did not find significant causal effects of VTE on the three classical lipids in reverse MR analysis. There is no significant causal relationship between three classical lipids (LDL, HDL and TGs) and VTE (DVT and PE) from a genetic point of view.
Topics: Humans; Venous Thromboembolism; Venous Thrombosis; Lipids; Pulmonary Embolism; Triglycerides; Lipoproteins, HDL; Mendelian Randomization Analysis; Polymorphism, Single Nucleotide; Genome-Wide Association Study
PubMed: 36890190
DOI: 10.1038/s41598-023-31067-z -
Journal of Applied Statistics 2023Discriminative subspace clustering (DSC) can make full use of linear discriminant analysis (LDA) to reduce the dimension of data and achieve effective clustering...
Discriminative subspace clustering (DSC) can make full use of linear discriminant analysis (LDA) to reduce the dimension of data and achieve effective clustering high-dimension data by clustering low-dimension data in discriminant subspace. However, most existing DSC algorithms do not consider the noise and outliers that may be contained in data sets, and when they are applied to the data sets with noise or outliers, and they often obtain poor performance due to the influence of noise and outliers. In this paper, we address the problem of the sensitivity of DSC to noise and outlier. Replacing the Euclidean distance in the objective function of LDA by an exponential non-Euclidean distance, we first develop a noise-insensitive LDA (NILDA) algorithm. Then, combining the proposed NILDA and a noise-insensitive fuzzy clustering algorithm: AFKM, we propose a noise-insensitive discriminative subspace fuzzy clustering (NIDSFC) algorithm. Experiments on some benchmark data sets show the effectiveness of the proposed NIDSFC algorithm.
PubMed: 36819072
DOI: 10.1080/02664763.2021.1937583 -
Economics Letters Feb 2022COVID-19 hit the economy in an unprecedented way, changing the data generating process of many series. We compare different seasonal adjustment methods through...
COVID-19 hit the economy in an unprecedented way, changing the data generating process of many series. We compare different seasonal adjustment methods through simulations, introducing outliers in the trend and seasonality to reproduce the heterogeneity in the series during COVID-19.
PubMed: 34931098
DOI: 10.1016/j.econlet.2021.110206 -
Sensors (Basel, Switzerland) Aug 2022Analysing human physiological data allows access to the health state and the state of mind of the subject individual. Whenever a person is sick, having a panic attack,...
Analysing human physiological data allows access to the health state and the state of mind of the subject individual. Whenever a person is sick, having a panic attack, happy or scared, physiological signals will be different. In terms of physiological signals, we focus, in this manuscript, on monitoring breathing patterns. The scope can be extended to also address heart rate and other variables. We describe an analysis of breathing rate patterns during activities including resting, walking, running and watching a movie. We model normal breathing behaviours by statistically analysing signals, processed to represent quantities of interest. We consider moving maximum/minimum, the amplitude and the Fourier transform of the respiration signal, working with different window sizes. We then learn a statistical model for the basal behaviour, per individual, and detect outliers. When outliers are detected, a system that incorporates our approach would send a visible signal through a smart garment or through other means. We describe alert generation performance in two datasets-one literature dataset and one collected as a field study for this work. In particular, when learning personal rest distributions for the breathing signals of 14 subjects, we see alerts generated more often when the same individual is running than when they are tested in rest conditions.
Topics: Humans; Models, Statistical; Respiration; Respiratory Rate; Rest
PubMed: 36016067
DOI: 10.3390/s22166306 -
Transfusion Medicine (Oxford, England) Jun 2023To investigate if time to initiate a blood transfusion after an informative laboratory test could feasibly be used by the transfusion medicine service as a metric to...
OBJECTIVES
To investigate if time to initiate a blood transfusion after an informative laboratory test could feasibly be used by the transfusion medicine service as a metric to monitor for transfusion delays.
BACKGROUND
Delayed transfusions may result in patient morbidity and mortality, but no standards for timely transfusion have been developed. Information technology tools could be implemented to identify gaps in provision of blood and to recognise areas of improvement.
MATERIALS AND METHODS
Data obtained from a children's hospital's data science platform and time from the release of laboratory results to the initiation of transfusions were calculated and weekly medians were used for trend analyses. Outlier events were obtained using locally estimated scatterplot smoothing and generalised extreme studentized deviate test.
RESULTS
Overall, the number of outlier events on the timing of transfusions based on patients' haemoglobin level and platelet count were small (n = 1 and n = 0 for 139 weeks, respectively). Investigation of these events for adverse clinical outcomes was non-significant.
CONCLUSIONS
Herein, we propose that the trends and outlier events could be further investigated and used to make decisions and implement protocols to improve patient care.
Topics: Child; Humans; Blood Transfusion; Platelet Count
PubMed: 36807938
DOI: 10.1111/tme.12960