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1.
BMC Infect Dis ; 24(1): 465, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724890

RESUMEN

BACKGROUND: Several models have been used to predict outbreaks during the COVID-19 pandemic, with limited success. We developed a simple mathematical model to accurately predict future epidemic waves. METHODS: We used data from the Ministry of Health, Labour and Welfare of Japan for newly confirmed COVID-19 cases. COVID-19 case data were summarized as weekly data, and epidemic waves were visualized and identified. The periodicity of COVID-19 in each prefecture of Japan was confirmed using time-series analysis and the autocorrelation coefficient, which was used to investigate the longer-term pattern of COVID-19 cases. Outcomes using the autocorrelation coefficient were visualized via a correlogram to capture the periodicity of the data. An algorithm for a simple prediction model of the seventh COVID-19 wave in Japan comprised three steps. Step 1: machine learning techniques were used to depict the regression lines for each epidemic wave, denoting the "rising trend line"; Step 2: an exponential function with good fit was identified from data of rising straight lines up to the sixth wave, and the timing of the rise of the seventh wave and speed of its spread were calculated; Step 3: a logistic function was created using the values calculated in Step 2 as coefficients to predict the seventh wave. The accuracy of the model in predicting the seventh wave was confirmed using data up to the sixth wave. RESULTS: Up to March 31, 2023, the correlation coefficient value was approximately 0.5, indicating significant periodicity. The spread of COVID-19 in Japan was repeated in a cycle of approximately 140 days. Although there was a slight lag in the starting and peak times in our predicted seventh wave compared with the actual epidemic, our developed prediction model had a fairly high degree of accuracy. CONCLUSION: Our newly developed prediction model based on the rising trend line could predict COVID-19 outbreaks up to a few months in advance with high accuracy. The findings of the present study warrant further investigation regarding application to emerging infectious diseases other than COVID-19 in which the epidemic wave has high periodicity.


Asunto(s)
COVID-19 , Modelos Teóricos , SARS-CoV-2 , COVID-19/epidemiología , Humanos , Japón/epidemiología , Brotes de Enfermedades , Pandemias , Algoritmos , Aprendizaje Automático , Predicción/métodos
2.
PLoS One ; 19(5): e0299603, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38728371

RESUMEN

Accurate forecasting of PM2.5 concentrations serves as a critical tool for mitigating air pollution. This study introduces a novel hybrid prediction model, termed MIC-CEEMDAN-CNN-BiGRU, for short-term forecasting of PM2.5 concentrations using a 24-hour historical data window. Utilizing the Maximal Information Coefficient (MIC) for feature selection, the model integrates Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN), Convolutional Neural Network (CNN), and Bidirectional Recurrent Gated Neural Network (BiGRU) to optimize predictive accuracy. We used 2016 PM2.5 monitoring data from Beijing, China as the empirical basis of this study and compared the model with several deep learning frameworks. RNN, LSTM, GRU, and other hybrid models based on GRU, respectively. The experimental results show that the prediction results of the hybrid model proposed in this question are more accurate than those of other models, and the R2 of the hybrid model proposed in this paper improves the R2 by nearly 5 percentage points compared with that of the single model; reduces the MAE by nearly 5 percentage points; and reduces the RMSE by nearly 11 percentage points. The results show that the hybrid prediction model proposed in this study is more accurate than other models in predicting PM2.5.


Asunto(s)
Redes Neurales de la Computación , Material Particulado , Material Particulado/análisis , Monitoreo del Ambiente/métodos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Predicción/métodos , Beijing
3.
Water Sci Technol ; 89(9): 2326-2341, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38747952

RESUMEN

In this paper, we address the critical task of 24-h streamflow forecasting using advanced deep-learning models, with a primary focus on the transformer architecture which has seen limited application in this specific task. We compare the performance of five different models, including persistence, long short-term memory (LSTM), Seq2Seq, GRU, and transformer, across four distinct regions. The evaluation is based on three performance metrics: Nash-Sutcliffe Efficiency (NSE), Pearson's r, and normalized root mean square error (NRMSE). Additionally, we investigate the impact of two data extension methods: zero-padding and persistence, on the model's predictive capabilities. Our findings highlight the transformer's superiority in capturing complex temporal dependencies and patterns in the streamflow data, outperforming all other models in terms of both accuracy and reliability. Specifically, the transformer model demonstrated a substantial improvement in NSE scores by up to 20% compared to other models. The study's insights emphasize the significance of leveraging advanced deep learning techniques, such as the transformer, in hydrological modeling and streamflow forecasting for effective water resource management and flood prediction.


Asunto(s)
Hidrología , Modelos Teóricos , Hidrología/métodos , Ríos , Movimientos del Agua , Predicción/métodos , Aprendizaje Profundo
4.
Water Sci Technol ; 89(9): 2367-2383, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38747954

RESUMEN

With the widespread application of machine learning in various fields, enhancing its accuracy in hydrological forecasting has become a focal point of interest for hydrologists. This study, set against the backdrop of the Haihe River Basin, focuses on daily-scale streamflow and explores the application of the Lasso feature selection method alongside three machine learning models (long short-term memory, LSTM; transformer for time series, TTS; random forest, RF) in short-term streamflow prediction. Through comparative experiments, we found that the Lasso method significantly enhances the model's performance, with a respective increase in the generalization capabilities of the three models by 21, 12, and 14%. Among the selected features, lagged streamflow and precipitation play dominant roles, with streamflow closest to the prediction date consistently being the most crucial feature. In comparison to the TTS and RF models, the LSTM model demonstrates superior performance and generalization capabilities in streamflow prediction for 1-7 days, making it more suitable for practical applications in hydrological forecasting in the Haihe River Basin and similar regions. Overall, this study deepens our understanding of feature selection and machine learning models in hydrology, providing valuable insights for hydrological simulations under the influence of complex human activities.


Asunto(s)
Aprendizaje Automático , Ríos , Hidrología , Modelos Teóricos , Movimientos del Agua , China , Predicción/métodos
5.
Sci Rep ; 14(1): 9962, 2024 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-38693172

RESUMEN

The COVID-19 pandemic caused by the novel SARS-COV-2 virus poses a great risk to the world. During the COVID-19 pandemic, observing and forecasting several important indicators of the epidemic (like new confirmed cases, new cases in intensive care unit, and new deaths for each day) helped prepare the appropriate response (e.g., creating additional intensive care unit beds, and implementing strict interventions). Various predictive models and predictor variables have been used to forecast these indicators. However, the impact of prediction models and predictor variables on forecasting performance has not been systematically well analyzed. Here, we compared the forecasting performance using a linear mixed model in terms of prediction models (mathematical, statistical, and AI/machine learning models) and predictor variables (vaccination rate, stringency index, and Omicron variant rate) for seven selected countries with the highest vaccination rates. We decided on our best models based on the Bayesian Information Criterion (BIC) and analyzed the significance of each predictor. Simple models were preferred. The selection of the best prediction models and the use of Omicron variant rate were considered essential in improving prediction accuracies. For the test data period before Omicron variant emergence, the selection of the best models was the most significant factor in improving prediction accuracy. For the test period after Omicron emergence, Omicron variant rate use was considered essential in deciding forecasting accuracy. For prediction models, ARIMA, lightGBM, and TSGLM generally performed well in both test periods. Linear mixed models with country as a random effect has proven that the choice of prediction models and the use of Omicron data was significant in determining forecasting accuracies for the highly vaccinated countries. Relatively simple models, fit with either prediction model or Omicron data, produced best results in enhancing forecasting accuracies with test data.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Predicción , SARS-CoV-2 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/virología , Predicción/métodos , SARS-CoV-2/inmunología , Vacunación , Aprendizaje Automático , Pandemias/prevención & control , Política de Salud , Teorema de Bayes , Modelos Estadísticos
6.
PLoS One ; 19(5): e0300216, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38691574

RESUMEN

This study integrates advanced machine learning techniques, namely Artificial Neural Networks, Long Short-Term Memory, and Gated Recurrent Unit models, to forecast monkeypox outbreaks in Canada, Spain, the USA, and Portugal. The research focuses on the effectiveness of these models in predicting the spread and severity of cases using data from June 3 to December 31, 2022, and evaluates them against test data from January 1 to February 7, 2023. The study highlights the potential of neural networks in epidemiology, especially concerning recent monkeypox outbreaks. It provides a comparative analysis of the models, emphasizing their capabilities in public health strategies. The research identifies optimal model configurations and underscores the efficiency of the Levenberg-Marquardt algorithm in training. The findings suggest that ANN models, particularly those with optimized Root Mean Squared Error, Mean Absolute Percentage Error, and the Coefficient of Determination values, are effective in infectious disease forecasting and can significantly enhance public health responses.


Asunto(s)
Predicción , Aprendizaje Automático , Mpox , Redes Neurales de la Computación , Humanos , Predicción/métodos , Mpox/epidemiología , Portugal/epidemiología , España/epidemiología , Brotes de Enfermedades , Canadá/epidemiología , Estados Unidos/epidemiología , Algoritmos
7.
PLoS One ; 19(4): e0297391, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38652720

RESUMEN

Platelet products are both expensive and have very short shelf lives. As usage rates for platelets are highly variable, the effective management of platelet demand and supply is very important yet challenging. The primary goal of this paper is to present an efficient forecasting model for platelet demand at Canadian Blood Services (CBS). To accomplish this goal, five different demand forecasting methods, ARIMA (Auto Regressive Integrated Moving Average), Prophet, lasso regression (least absolute shrinkage and selection operator), random forest, and LSTM (Long Short-Term Memory) networks are utilized and evaluated via a rolling window method. We use a large clinical dataset for a centralized blood distribution centre for four hospitals in Hamilton, Ontario, spanning from 2010 to 2018 and consisting of daily platelet transfusions along with information such as the product specifications, the recipients' characteristics, and the recipients' laboratory test results. This study is the first to utilize different methods from statistical time series models to data-driven regression and machine learning techniques for platelet transfusion using clinical predictors and with different amounts of data. We find that the multivariable approaches have the highest accuracy in general, however, if sufficient data are available, a simpler time series approach appears to be sufficient. We also comment on the approach to choose predictors for the multivariable models.


Asunto(s)
Predicción , Transfusión de Plaquetas , Humanos , Transfusión de Plaquetas/métodos , Predicción/métodos , Plaquetas , Masculino , Femenino , Ontario , Aprendizaje Automático , Persona de Mediana Edad , Modelos Estadísticos , Anciano , Análisis Multivariante
8.
Comput Biol Med ; 175: 108442, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38678939

RESUMEN

In the global effort to address the outbreak of the new coronavirus pneumonia (COVID-19) pandemic, accurate forecasting of epidemic patterns has become crucial for implementing successful interventions aimed at preventing and controlling the spread of the disease. The correct prediction of the course of COVID-19 outbreaks is a complex and challenging task, mainly because of the significant volatility in the data series related to COVID-19. Previous studies have been limited by the exclusive use of individual forecasting techniques in epidemic modeling, disregarding the integration of diverse prediction procedures. The lack of attention to detail in this situation can yield worse-than-ideal results. Consequently, this study introduces a novel ensemble framework that integrates three machine learning methods (kernel ridge regression (KRidge), Deep random vector functional link (dRVFL), and ridge regression) within a linear relationship (L-KRidge-dRVFL-Ridge). The optimization of this framework is accomplished through a distinctive approach, specifically adaptive differential evolution and particle swarm optimization (A-DEPSO). Moreover, an effective decomposition method, known as time-varying filter empirical mode decomposition (TVF-EMD), is employed to decompose the input variables. A feature selection technique, specifically using the light gradient boosting machine (LGBM), is also implemented to extract the most influential input variables. The daily datasets of COVID-19 collected from two countries, namely Italy and Poland, were used as the experimental examples. Additionally, all models are implemented to forecast COVID-19 at two-time horizons: 10- and 14-day ahead (t+10 and t+14). According to the results, the proposed model can yield higher correlation coefficient (R) for both case studies: Italy (t+10 = 0.965, t+14 = 0.961) and Poland (t+10 = 0.952, t+14 = 0.940) than the other models. The experimental results demonstrate that the model suggested in this paper has outstanding results in various kinds of complex epidemic prediction situations. The proposed ensemble model demonstrates exceptional accuracy and resilience, outperforming all similar models in terms of efficacy.


Asunto(s)
COVID-19 , Predicción , SARS-CoV-2 , Humanos , COVID-19/epidemiología , Predicción/métodos , Aprendizaje Automático , Pandemias , Modelos Estadísticos , Algoritmos , Modelos Epidemiológicos
10.
Artículo en Inglés | MEDLINE | ID: mdl-38673408

RESUMEN

The SARS-CoV-2 global pandemic prompted governments, institutions, and researchers to investigate its impact, developing strategies based on general indicators to make the most precise predictions possible. Approaches based on epidemiological models were used but the outcomes demonstrated forecasting with uncertainty due to insufficient or missing data. Besides the lack of data, machine-learning models including random forest, support vector regression, LSTM, Auto-encoders, and traditional time-series models such as Prophet and ARIMA were employed in the task, achieving remarkable results with limited effectiveness. Some of these methodologies have precision constraints in dealing with multi-variable inputs, which are important for problems like pandemics that require short and long-term forecasting. Given the under-supply in this scenario, we propose a novel approach for time-series prediction based on stacking auto-encoder structures using three variations of the same model for the training step and weight adjustment to evaluate its forecasting performance. We conducted comparison experiments with previously published data on COVID-19 cases, deaths, temperature, humidity, and air quality index (AQI) in São Paulo City, Brazil. Additionally, we used the percentage of COVID-19 cases from the top ten affected countries worldwide until May 4th, 2020. The results show 80.7% and 10.3% decrease in RMSE to entire and test data over the distribution of 50 trial-trained models, respectively, compared to the first experiment comparison. Also, model type#3 achieved 4th better overall ranking performance, overcoming the NBEATS, Prophet, and Glounts time-series models in the second experiment comparison. This model shows promising forecast capacity and versatility across different input dataset lengths, making it a prominent forecasting model for time-series tasks.


Asunto(s)
COVID-19 , Predicción , COVID-19/epidemiología , Humanos , Predicción/métodos , Brasil/epidemiología , Pandemias , Aprendizaje Automático , SARS-CoV-2 , Modelos Estadísticos , Modelos Epidemiológicos
11.
BMC Infect Dis ; 24(1): 432, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654199

RESUMEN

BACKGROUND: Influenza-like illness (ILI) imposes a significant burden on patients, employers and society. However, there is no analysis and prediction at the hospital level in Chongqing. We aimed to characterize the seasonality of ILI, examine age heterogeneity in visits, and predict ILI peaks and assess whether they affect hospital operations. METHODS: The multiplicative decomposition model was employed to decompose the trend and seasonality of ILI, and the Seasonal Auto-Regressive Integrated Moving Average with exogenous factors (SARIMAX) model was used for the trend and short-term prediction of ILI. We used Grid Search and Akaike information criterion (AIC) to calibrate and verify the optimal hyperparameters, and verified the residuals of the multiplicative decomposition and SARIMAX model, which are both white noise. RESULTS: During the 12-year study period, ILI showed a continuous upward trend, peaking in winter (Dec. - Jan.) and a small spike in May-June in the 2-4-year-old high-risk group for severe disease. The mean length of stay (LOS) in ILI peaked around summer (about Aug.), and the LOS in the 0-1 and ≥ 65 years old severely high-risk group was more irregular than the others. We found some anomalies in the predictive analysis of the test set, which were basically consistent with the dynamic zero-COVID policy at the time. CONCLUSION: The ILI patient visits showed a clear cyclical and seasonal pattern. ILI prevention and control activities can be conducted seasonally on an annual basis, and age heterogeneity should be considered in the health resource planning. Targeted immunization policies are essential to mitigate potential pandemic threats. The SARIMAX model has good short-term forecasting ability and accuracy. It can help explore the epidemiological characteristics of ILI and provide an early warning and decision-making basis for the allocation of medical resources related to ILI visits.


Asunto(s)
Predicción , Gripe Humana , Estaciones del Año , Humanos , Gripe Humana/epidemiología , China/epidemiología , Persona de Mediana Edad , Predicción/métodos , Niño , Preescolar , Adulto , Anciano , Lactante , Adolescente , Adulto Joven , Recién Nacido , Masculino , Femenino , Tiempo de Internación/estadística & datos numéricos , Modelos Estadísticos
12.
PLoS One ; 19(4): e0302197, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38662755

RESUMEN

Our study aims to investigate the interdependence between international stock markets and sentiments from financial news in stock forecasting. We adopt the Temporal Fusion Transformers (TFT) to incorporate intra and inter-market correlations and the interaction between the information flow, i.e. causality, of financial news sentiment and the dynamics of the stock market. The current study distinguishes itself from existing research by adopting Dynamic Transfer Entropy (DTE) to establish an accurate information flow propagation between stock and sentiments. DTE has the advantage of providing time series that mine information flow propagation paths between certain parts of the time series, highlighting marginal events such as spikes or sudden jumps, which are crucial in financial time series. The proposed methodological approach involves the following elements: a FinBERT-based textual analysis of financial news articles to extract sentiment time series, the use of the Transfer Entropy and corresponding heat maps to analyze the net information flows, the calculation of the DTE time series, which are considered as co-occurring covariates of stock Price, and TFT-based stock forecasting. The Dow Jones Industrial Average index of 13 countries, along with daily financial news data obtained through the New York Times API, are used to demonstrate the validity and superiority of the proposed DTE-based causality method along with TFT for accurate stock Price and Return forecasting compared to state-of-the-art time series forecasting methods.


Asunto(s)
Predicción , Inversiones en Salud , Inversiones en Salud/economía , Predicción/métodos , Humanos , Entropía , Modelos Económicos , Comercio/tendencias
13.
PLoS One ; 19(4): e0299530, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38662787

RESUMEN

Typhoons are natural disasters characterized by their high frequency of occurrence and significant impact, often leading to secondary disasters. In this study, we propose a prediction model for the trend of typhoon disasters. Utilizing neural networks, we calculate the forgetting gate, update gate, and output gate to forecast typhoon intensity, position, and disaster trends. By employing the concept of big data, we collected typhoon data using Python technology and verified the model's performance. Overall, the model exhibited a good fit, particularly for strong tropical storms. However, improvements are needed to enhance the forecasting accuracy for tropical depressions, typhoons, and strong typhoons. The model demonstrated a small average error in predicting the latitude and longitude of the typhoon's center position, and the predicted path closely aligned with the actual trajectory.


Asunto(s)
Macrodatos , Tormentas Ciclónicas , Predicción , Predicción/métodos , Redes Neurales de la Computación , Desastres , Humanos , Planificación en Desastres/métodos
14.
Ecology ; 105(5): e4297, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38613235

RESUMEN

Forecasting invasion risk under future climate conditions is critical for the effective management of invasive species, and species distribution models (SDMs) are key tools for doing so. However, SDM-based forecasts are uncertain, especially when correlative statistical models extrapolate to nonanalog environmental domains, such as future climate conditions. Different assumptions about the functional form of the temperature-suitability relationship can impact predicted habitat suitability under novel conditions. Hence, methods to understand the sources of uncertainty are critical when applying SDMs. Here, we use high-resolution predictions of lake water temperatures to project changes in habitat suitability under future climate conditions for an invasive macrophyte (Myriophyllym spicatum). Future suitability was predicted using five global circulation models and three statistical models that assumed different species-temperature functional responses. The suitability of lakes for M. spicatum was overall predicted to increase under future climate conditions, but the magnitude and direction of change in suitability varied greatly among lakes. Variability was most pronounced for lakes under nonanalog temperature conditions, indicating that predictions for these lakes remained highly uncertain. Integrating predictions from SDMs that differ in their species-environment response function, while explicitly quantifying uncertainty across analog and nonanalog domains, can provide a more robust and useful approach to forecasting invasive species distribution under climate change.


Asunto(s)
Cambio Climático , Especies Introducidas , Modelos Biológicos , Incertidumbre , Lagos , Demografía , Magnoliopsida/fisiología , Ecosistema , Temperatura , Predicción/métodos
15.
Nature ; 627(8004): 559-563, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38509278

RESUMEN

Floods are one of the most common natural disasters, with a disproportionate impact in developing countries that often lack dense streamflow gauge networks1. Accurate and timely warnings are critical for mitigating flood risks2, but hydrological simulation models typically must be calibrated to long data records in each watershed. Here we show that artificial intelligence-based forecasting achieves reliability in predicting extreme riverine events in ungauged watersheds at up to a five-day lead time that is similar to or better than the reliability of nowcasts (zero-day lead time) from a current state-of-the-art global modelling system (the Copernicus Emergency Management Service Global Flood Awareness System). In addition, we achieve accuracies over five-year return period events that are similar to or better than current accuracies over one-year return period events. This means that artificial intelligence can provide flood warnings earlier and over larger and more impactful events in ungauged basins. The model developed here was incorporated into an operational early warning system that produces publicly available (free and open) forecasts in real time in over 80 countries. This work highlights a need for increasing the availability of hydrological data to continue to improve global access to reliable flood warnings.


Asunto(s)
Inteligencia Artificial , Simulación por Computador , Inundaciones , Predicción , Predicción/métodos , Reproducibilidad de los Resultados , Ríos , Hidrología , Calibración , Factores de Tiempo , Planificación en Desastres/métodos
16.
Emergencias (Sant Vicenç dels Horts) ; 36(1): 48-62, feb. 2024. ilus, tab
Artículo en Español | IBECS | ID: ibc-229849

RESUMEN

Objetivo. La obtención de hemocultivos (HC) se realiza en el 15% de los pacientes atendidos con sospecha de infección en los servicios de urgencias (SU) con una rentabilidad diagnóstica variable (2-20%). La mortalidad a 30 días de estos pacientes con bacteriemia es elevada, doble o triple que el resto con el mismo proceso. Así, encontrar un modelo predictivo de bacteriemia eficaz y aplicable en los SU sería muy importante. Clásicamente, el modelo de Shapiro ha sido la referencia en todo el mundo. El objetivo de esta revisión sistemática (RS) es comparar la capacidad para predecir bacteriemia en los SU de los distintos modelos predictivos publicados desde el año 2008 (fecha de publicación del modelo de Shapiro). Métodos. Se realiza una RS siguiendo la normativa PRISMA en las bases de datos de PubMed, Web of Science, EMBASE, Lilacs, Cochrane, Epistemonikos, Tripdatabase y ClinicalTrials.gov desde enero de 2008 hasta 31 mayo 2023 sin restricción de idiomas y utilizando una combinación de términos MESH: “Bacteremia/Bacteraemia/Blood Stream Infection”, “Prediction Model/Clinical Prediction Rule/Risk Prediction Model”, “Emergencies/Emergency/Emergency Department” y “Adults”. Se incluyeron estudios de cohortes observacionales (analíticos de rendimiento diagnóstico). Para valorar la calidad del método empleado y el riesgo de sesgos de los artículos incluidos se utilizó la NewcastleOttawa Scale (NOS). No se incluyeron estudios de casos y controles, revisiones narrativas y en otros tipos de artículos. No se realizaron técnicas de metanálisis, pero los resultados se compararon narrativamente. El protocolo de la RS se registró en PROSPERO (CRD42023426327). Resultados. Se identificaron 917 artículos y se analizaron finalmente 20 que cumplían los criterios de inclusión. Los estudios incluidos contienen 33.182 HC procesados con 5.074 bacteriemias (15,3%). Once estudios fueron calificados de calidad alta, 7 moderada y 2 baja... (AU)


Objective. Blood cultures are ordered in emergency departments for 15% of patients with suspected infection. The diagnostic yield varies from 2% to 20%. Thirty-day mortality in patients with bacteremia is high, doubling or tripling the rate in patients with the same infection but without bacteremia. Thus, finding an effective model to predict bacteremia that is applicable in emergency departments is an important goal. Shapiro’s model is the one traditionally used as a reference internationally. The aim of this systematic review was to compare the predictive power of bacteremia risk models published since 2008, when Shapiro’s model first appeared. Methods. We followed the recommendations of the Preferred Reporting Items for Systematic Reviews and MetaAnalyses (PRISMA) statement, searching in the following databases for articles published between January 2008 and May 31, 2023: PubMed, Web of Science, EMBASE, Lilacs, Cochrane, Epistemonikos, Trip Medical Database, and ClinicalTrials.gov. No language restrictions were specified. The search terms were the following Medical Subject Headings: bacteremia/bacteraemia/blood stream infection, prediction model/clinical prediction rule/risk prediction model, emergencies/emergency/emergency department, and adults. Observational cohort studies analyzing diagnostic yield were included; case-control studies, narrative reviews, and other types of articles were excluded. The Newcastle-Ottawa Scale was used to score quality and risk of bias in the included studies. The results were compared descriptively, without meta-analysis. The protocol was included in the PROSPERO register (CRD42023426327). Results. Twenty studies out of a total of 917 were found to meet the inclusion criteria. The included studies together analyzed 33 182 blood cultures, which detected 5074 cases of bacteremia (15.3%). Eleven studies were of high quality, 7 of moderate quality, and 2 of low quality... (AU)


Asunto(s)
Bacteriemia , Predicción/métodos , Servicios Médicos de Urgencia
17.
Emergencias (Sant Vicenç dels Horts) ; 36(1): 48-62, feb. 2024. ilus, tab
Artículo en Español | IBECS | ID: ibc-EMG-467

RESUMEN

Objetivo. La obtención de hemocultivos (HC) se realiza en el 15% de los pacientes atendidos con sospecha de infección en los servicios de urgencias (SU) con una rentabilidad diagnóstica variable (2-20%). La mortalidad a 30 días de estos pacientes con bacteriemia es elevada, doble o triple que el resto con el mismo proceso. Así, encontrar un modelo predictivo de bacteriemia eficaz y aplicable en los SU sería muy importante. Clásicamente, el modelo de Shapiro ha sido la referencia en todo el mundo. El objetivo de esta revisión sistemática (RS) es comparar la capacidad para predecir bacteriemia en los SU de los distintos modelos predictivos publicados desde el año 2008 (fecha de publicación del modelo de Shapiro). Métodos. Se realiza una RS siguiendo la normativa PRISMA en las bases de datos de PubMed, Web of Science, EMBASE, Lilacs, Cochrane, Epistemonikos, Tripdatabase y ClinicalTrials.gov desde enero de 2008 hasta 31 mayo 2023 sin restricción de idiomas y utilizando una combinación de términos MESH: “Bacteremia/Bacteraemia/Blood Stream Infection”, “Prediction Model/Clinical Prediction Rule/Risk Prediction Model”, “Emergencies/Emergency/Emergency Department” y “Adults”. Se incluyeron estudios de cohortes observacionales (analíticos de rendimiento diagnóstico). Para valorar la calidad del método empleado y el riesgo de sesgos de los artículos incluidos se utilizó la NewcastleOttawa Scale (NOS). No se incluyeron estudios de casos y controles, revisiones narrativas y en otros tipos de artículos. No se realizaron técnicas de metanálisis, pero los resultados se compararon narrativamente. El protocolo de la RS se registró en PROSPERO (CRD42023426327). Resultados. Se identificaron 917 artículos y se analizaron finalmente 20 que cumplían los criterios de inclusión. Los estudios incluidos contienen 33.182 HC procesados con 5.074 bacteriemias (15,3%). Once estudios fueron calificados de calidad alta, 7 moderada y 2 baja... (AU)


Objective. Blood cultures are ordered in emergency departments for 15% of patients with suspected infection. The diagnostic yield varies from 2% to 20%. Thirty-day mortality in patients with bacteremia is high, doubling or tripling the rate in patients with the same infection but without bacteremia. Thus, finding an effective model to predict bacteremia that is applicable in emergency departments is an important goal. Shapiro’s model is the one traditionally used as a reference internationally. The aim of this systematic review was to compare the predictive power of bacteremia risk models published since 2008, when Shapiro’s model first appeared. Methods. We followed the recommendations of the Preferred Reporting Items for Systematic Reviews and MetaAnalyses (PRISMA) statement, searching in the following databases for articles published between January 2008 and May 31, 2023: PubMed, Web of Science, EMBASE, Lilacs, Cochrane, Epistemonikos, Trip Medical Database, and ClinicalTrials.gov. No language restrictions were specified. The search terms were the following Medical Subject Headings: bacteremia/bacteraemia/blood stream infection, prediction model/clinical prediction rule/risk prediction model, emergencies/emergency/emergency department, and adults. Observational cohort studies analyzing diagnostic yield were included; case-control studies, narrative reviews, and other types of articles were excluded. The Newcastle-Ottawa Scale was used to score quality and risk of bias in the included studies. The results were compared descriptively, without meta-analysis. The protocol was included in the PROSPERO register (CRD42023426327). Results. Twenty studies out of a total of 917 were found to meet the inclusion criteria. The included studies together analyzed 33 182 blood cultures, which detected 5074 cases of bacteremia (15.3%). Eleven studies were of high quality, 7 of moderate quality, and 2 of low quality... (AU)


Asunto(s)
Bacteriemia , Predicción/métodos , Servicios Médicos de Urgencia
18.
J Epidemiol Glob Health ; 14(1): 234-242, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38353917

RESUMEN

BACKGROUND: Malaria remains a formidable worldwide health challenge, with approximately half of the global population at high risk of catching the infection. This research study aimed to address the pressing public health issue of malaria's escalating prevalence in Khyber Pakhtunkhwa (KP) province, Pakistan, and endeavors to estimate the trend for the future growth of the infection. METHODS: The data were collected from the IDSRS of KP, covering a period of 5 years from 2018 to 2022. We proposed a hybrid model that integrated Prophet and TBATS methods, allowing us to efficiently capture the complications of the malaria data and improve forecasting accuracy. To ensure an inclusive assessment, we compared the prediction performance of the proposed hybrid model with other widely used time series models, such as ARIMA, ETS, and ANN. The models were developed through R-statistical software (version 4.2.2). RESULTS: For the prediction of malaria incidence, the suggested hybrid model (Prophet and TBATS) surpassed commonly used time series approaches (ARIMA, ETS, and ANN). Hybrid model assessment metrics portrayed higher accuracy and reliability with lower MAE (8913.9), RMSE (3850.2), and MAPE (0.301) values. According to our forecasts, malaria infections were predicted to spread around 99,301 by December 2023. CONCLUSIONS: We found the hybrid model (Prophet and TBATS) outperformed common time series approaches for forecasting malaria. By December 2023, KP's malaria incidence is expected to be around 99,301, making future incidence forecasts important. Policymakers will be able to use these findings to curb disease and implement efficient policies for malaria control.


Asunto(s)
Predicción , Malaria , Pakistán/epidemiología , Humanos , Malaria/epidemiología , Predicción/métodos , Incidencia , Modelos Estadísticos
19.
Environ Res ; 249: 118329, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38325781

RESUMEN

Pollutant emissions from chemical plants are a major concern in the context of environmental safety. A reliable emission forecasting model can provide important information for optimizing the process and improving the environmental performance. In this work, forecasting models are developed for the prediction of SO2 emission from a Sulfur Recovery Unit (SRU). Since SRUs incorporate complex chemical reactions, first-principle models are not suitable to predict emission levels based on a given feed condition. Accordingly, artificial intelligence-based models such as standard machine learning (ML) algorithms, multi-layer perceptron (MLP), long short-term memory (LSTM), one-dimensional convolution (1D-CNN), and CNN-LSTM models were tested, and their performance was evaluated. The input features and hyperparameters of the models were optimized to achieve maximum performance. The performance was evaluated in terms of mean squared error (MSE) and mean absolute percentage Error (MAPE) for 1 h, 3 h and 5 h ahead of forecasting. The reported results show that the CNN-LSTM encoder-decoder model outperforms other tested models, with its superiority becoming more pronounced as the forecasting horizon increased from 1 h to 5 h. For the 5-h ahead forecasting, the proposed model showed a MAPE advantage of 17.23%, 4.41%, and 2.83%, respectively over the 1D-CNN, Deep LSTM, and single-layer LSTM models in the larger dataset.


Asunto(s)
Contaminantes Atmosféricos , Inteligencia Artificial , Predicción , Incineración , Dióxido de Azufre , Dióxido de Azufre/análisis , Predicción/métodos , Contaminantes Atmosféricos/análisis , Azufre/análisis , Modelos Teóricos , Monitoreo del Ambiente/métodos , Redes Neurales de la Computación , Aprendizaje Automático
20.
Environ Res ; 249: 118438, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38350546

RESUMEN

Air pollution constitutes a substantial peril to human health, thereby catalyzing the evolution of an array of air quality prediction models. These models span from mechanistic and statistical strategies to machine learning methodologies. The burgeoning field of deep learning has given rise to a plethora of advanced models, which have demonstrated commendable performance. However, previous investigations have overlooked the salience of quantifying prediction uncertainties and potential future interconnections among air monitoring stations. Moreover, prior research typically utilized static predetermined spatial relationships, neglecting dynamic dependencies. To address these limitations, we propose a model named Dynamic Spatial-Temporal Denoising Diffusion Probabilistic Model (DST-DDPM) for air quality prediction. Our model is underpinned by the renowned denoising diffusion model, aiding us in discerning indeterminacy. In order to encapsulate dynamic patterns, we design a dynamic context encoder to generate dynamic adjacency matrices, whilst maintaining static spatial information. Furthermore, we incorporate a spatial-temporal denoising model to concurrently learn both spatial and temporal dependencies. Authenticating our model's performance using a real-world dataset collected in Beijing, the outcomes indicate that our model eclipses other baseline models in terms of both short-term and long-term predictions by 1.36% and 11.62% respectively. Finally, we conduct a case study to exhibit our model's capacity to quantify uncertainties.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Monitoreo del Ambiente , Predicción , Modelos Estadísticos , Incertidumbre , Contaminación del Aire/análisis , Monitoreo del Ambiente/métodos , Contaminantes Atmosféricos/análisis , Predicción/métodos , Análisis Espacio-Temporal , Beijing , Material Particulado/análisis
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