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1.
Entropy (Basel) ; 26(1)2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38248187

RESUMEN

Parameter estimation is an important component of statistical inference, and how to improve the accuracy of parameter estimation is a key issue in research. This paper proposes a linear Bayesian estimation for estimating parameters in a misrecorded Poisson distribution. The linear Bayesian estimation method not only adopts prior information but also avoids the cumbersome calculation of posterior expectations. On the premise of ensuring the accuracy and stability of computational results, we derived the explicit solution of the linear Bayesian estimation. Its superiority was verified through numerical simulations and illustrative examples.

2.
J Affect Disord ; 350: 916-925, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38244788

RESUMEN

BACKGROUND: Which life satisfaction components could be a target of positive psychological interventions for longevity is largely unknown. We aimed to investigate association of the composite measure of life satisfaction and its individual components with mortality. METHODS: This cohort study included UK Biobank participants who responded to questions concerning five components of life satisfaction at baseline. We generated a composite score representing overall life satisfaction, ranging from 0 (lowest) to 5 (highest). The outcomes were all-cause and cause-specific mortality. We used multivariable Cox regression to estimate hazard ratios (HR) for the associations of interest. RESULTS: Among 165,842 eligible participants, 12,261 all-cause deaths were observed over a median of 12.9-year follow-up. Overall life satisfaction was inversely associated with all-cause mortality (adjusted HR 0.94 [95% CI: 0.93-0.95] per 1 score increment). Health satisfaction showed the strongest association with all-cause mortality, with a fully adjusted HR of 0.52 (95% CI: 0.49-0.55) for high/extreme satisfaction and 0.63 (95% CI: 0.59-0.66) for moderate satisfaction, compared with unsatisfaction (P-trend<0.001), independent of other satisfaction components, regardless of physical health and sociodemographics. The association for family, friendship, work and financial satisfaction was attenuated when adjusted for other life satisfaction components. Similar findings were observed for cause-specific mortality. LIMITATIONS: Observational study with single baseline measurement of life satisfaction precludes the ability to establish causal relationship. CONCLUSIONS: Higher overall life satisfaction was associated with lower mortality. As the major contributor to lower mortality regardless of physical health and sociodemographics, health satisfaction could be an important target of positive psychological interventions for longevity.


Asunto(s)
Enfermedades Cardiovasculares , Satisfacción Personal , Humanos , Estudios de Cohortes , Causas de Muerte , Estudios Prospectivos , Factores de Riesgo
3.
JAMA Netw Open ; 6(3): e234219, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36951864

RESUMEN

Importance: Systematic reviews can help to justify a new randomized clinical trial (RCT), inform its design, and interpret its results in the context of prior evidence. Objective: To assess trends and factors associated with citing (a marker of the use of) prior systematic reviews in RCT reports. Design, Setting, and Participants: This cross-sectional study investigated 737 Cochrane reviews assessing health interventions to identify 4003 eligible RCTs, defined as those included in an updated version but not in the first version of a Cochrane review and published 2 years after the first version of the Cochrane review was published. Main Outcomes and Measures: The primary outcome was the citation of prior systematic reviews, Cochrane or others, as determined by screening references of eligible RCTs. Factors that may be associated with the citation of prior systematic reviews were also examined. Results: Among 4003 eligible RCTs, 1241 studies (31.0%) cited Cochrane reviews, 1698 studies (42.4%) cited prior non-Cochrane reviews, and 2265 studies (56.6%) cited either type of systematic review or both; 1738 RCTs (43.4%) cited no systematic reviews. The percentage of RCTs citing prior Cochrane reviews, non-Cochrane reviews, and either or both types of review increased from 28 studies (15.3%), 46 studies (25.1%), and 65 studies (35.5%) of 183 RCTs before 2008 to 42 studies (40.8%), 65 studies (64.1%), and 73 studies (71.8%) of 102 RCTs since 2020, respectively; the annual increases were 1.9% (95% CI, 1.4%-2.3%), 3.3% (95% CI, 2.9%-3.7%), and 3.0% (95% CI, 2.5%-3.5%), respectively. The proportion of RCTs citating prior systematic reviews varied considerably across clinical specialties, ranging from 28 of 106 RCTs (26.4%) in ophthalmology to 386 of 553 RCTs (69.8%) in psychiatry (P < .001). RCTs with 100 participants or more (risk ratio [RR], 1.16; 95% CI, 1.03-1.30), nonindustry funding (RR, 1.43; 95% CI, 1.27-1.61), and authors from high-income countries (RR, 1.10; 95% CI, 1.03-1.17) were more likely to cite systematic reviews than those with fewer than 100 participants, industry funding, and authors from low- and middle-income countries, respectively. A journal requirement to cite systematic reviews was not associated with the likelihood of citing a systematic review. Conclusions and Relevance: This study found that the citation of prior systematic reviews in RCT reports improved over time, but approximately 40% of RCTs failed to do so. These findings suggest that reference to prior evidence for initiating, designing, and reporting RCTs should be further emphasized to assure clinical relevance, improve methodological quality, and facilitate interpretation of new results.


Asunto(s)
Ensayos Clínicos Controlados Aleatorios como Asunto , Revisiones Sistemáticas como Asunto , Humanos
4.
Lancet Microbe ; 4(4): e236-e246, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36868258

RESUMEN

BACKGROUND: The efficacy of SARS-CoV-2 vaccines in preventing severe COVID-19 illness and death is uncertain due to the rarity of data in individual trials. How well the antibody concentrations can predict the efficacy is also uncertain. We aimed to assess the efficacy of these vaccines in preventing SARS-CoV-2 infections of different severities and the dose-response relationship between the antibody concentrations and efficacy. METHODS: We did a systematic review and meta-analysis of randomised controlled trials (RCTs). We searched PubMed, Embase, Scopus, Web of Science, Cochrane Library, WHO, bioRxiv, and medRxiv for papers published between Jan 1, 2020 and Sep 12, 2022. RCTs on the efficacy of SARS-CoV-2 vaccines were eligible. Risk of bias was assessed using the Cochrane tool. A frequentist, random-effects model was used to combine efficacy for common outcomes (ie, symptomatic and asymptomatic infections) and a Bayesian random-effects model was used for rare outcomes (ie, hospital admission, severe infection, and death). Potential sources of heterogeneity were investigated. The dose-response relationships of neutralising, spike-specific IgG and receptor binding domain-specific IgG antibody titres with efficacy in preventing SARS-CoV-2 symptomatic and severe infections were examined by meta-regression. This systematic review is registered with PROSPERO, CRD42021287238. FINDINGS: 28 RCTs (n=286 915 in vaccination groups and n=233 236 in placebo groups; median follow-up 1-6 months after last vaccination) across 32 publications were included in this review. The combined efficacy of full vaccination was 44·5% (95% CI 27·8-57·4) for preventing asymptomatic infections, 76·5% (69·8-81·7) for preventing symptomatic infections, 95·4% (95% credible interval 88·0-98·7) for preventing hospitalisation, 90·8% (85·5-95·1) for preventing severe infection, and 85·8% (68·7-94·6) for preventing death. There was heterogeneity in the efficacy of SARS-CoV-2 vaccines against asymptomatic and symptomatic infections but insufficient evidence to suggest whether the efficacy could differ according to the type of vaccine, age of the vaccinated individual, and between-dose interval (p>0·05 for all). Vaccine efficacy against symptomatic infection waned over time after full vaccination, with an average decrease of 13·6% (95% CI 5·5-22·3; p=0·0007) per month but can be enhanced by a booster. We found a significant non-linear relationship between each type of antibody and efficacy against symptomatic and severe infections (p<0·0001 for all), but there remained considerable heterogeneity in the efficacy, which cannot be explained by antibody concentrations. The risk of bias was low in most studies. INTERPRETATION: The efficacy of SARS-CoV-2 vaccines is higher for preventing severe infection and death than for preventing milder infection. Vaccine efficacy wanes over time but can be enhanced by a booster. Higher antibody titres are associated with higher estimates of efficacy but precise predictions are difficult due to large unexplained heterogeneity. These findings provide an important knowledge base for interpretation and application of future studies on these issues. FUNDING: Shenzhen Science and Technology Programs.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , Vacunas contra la COVID-19/uso terapéutico , Infecciones Asintomáticas , COVID-19/prevención & control , SARS-CoV-2 , Inmunoglobulina G , Ensayos Clínicos Controlados Aleatorios como Asunto
5.
Cancer Epidemiol Biomarkers Prev ; 32(4): 531-541, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36716122

RESUMEN

BACKGROUND: Previous studies indicated that glucosamine supplements may have a general anticancer effect. This study aimed to assess whether the potential effect differs across different types of cancers in a large prospective cohort study. METHODS: All participants from the UK Biobank who were free of cancers and had complete information on glucosamine use at baseline were included and followed up from 2006 until 2021. Cox proportional hazards models were used to assess the associations between regular glucosamine use and different site-specific cancers. Subgroup analyses were performed to explore potential interactions. Several sensitivity analyses were conducted to assess the robustness of the main findings. RESULTS: A total of 450,207 eligible participants (mean age: 56.2 years; females: 53.3%) were included, of whom 84,895 (18.9%) reported regular glucosamine use at baseline. During a median of 12.5 years follow-up, glucosamine use was significantly associated with an increased risk of overall cancer [HR, 1.04; 95% confidence interval (CI), 1.01-1.06], skin cancer (HR, 1.11; 95% CI, 1.07-1.15), and prostate cancer (HR, 1.07; 95% CI, 1.01-1.13), and with a reduced risk of lung cancer (HR, 0.88; 95% CI, 0.79-0.97) after adjusting for potential confounders. Statistical interaction was observed for gender, age, and education for the association of glucosamine use with overall cancer risk (all Pinteraction < 0.027). These results remained unchanged in the sensitivity analyses. CONCLUSIONS: Regular glucosamine use was associated with lower risk of lung cancer but higher risk of skin cancer, prostate cancer, and overall cancer. IMPACT: The roles of glucosamine use potentially differ in the development of different site-specific cancers.


Asunto(s)
Neoplasias Pulmonares , Neoplasias de la Próstata , Neoplasias Cutáneas , Masculino , Humanos , Persona de Mediana Edad , Glucosamina/uso terapéutico , Estudios Prospectivos , Factores de Riesgo , Suplementos Dietéticos , Neoplasias Pulmonares/prevención & control
6.
Front Oncol ; 12: 1002693, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36531057

RESUMEN

Background: Conventional universal endoscopic screening with pathology-based endoscopic re-examination for esophageal squamous cell carcinoma is in need of reform in China. We established a "two-step" precision screening strategy using two risk prediction models and have evaluated the cost-effectiveness of this precision strategy compared with the traditional strategy based on a large population-level randomized controlled trial from a healthcare provider's perspective. Methods: Four precision screening strategies with different risk cutoffs at baseline screening and endoscopic surveillance were constructed, and then compared with traditional strategy through modeling using subjects from the screening cohort of the ESECC (Endoscopic Screening for Esophageal Cancer in China) trial. Total screening costs and the number of SDA (severe dysplasia and above in lesions of the esophagus) cases were obtained to calculate the average screening cost per SDA detected, the incremental cost-effectiveness ratio (ICER) and protection rates. Sensitivity analysis was conducted to evaluate uncertainties. Results: Compared to traditional strategy, all precision screening strategies have much lower average costs for detection of one SDA case ($7,148~$11,537 vs. $14,944). In addition, precision strategies 1&2 (strategies 1,2,3,4 described below) achieved higher effectiveness (143~150 vs. 136) and higher protection rates (87.7%~92.0% vs. 83.4%) at lower cost ($1,649,727~$1,672,221 vs. $2,032,386), generating negative ICERs (-$54,666/SDA~-$25,726/SDA) when compared to the traditional strategy. The optimal strategies within different willingness-to-pay (WTP) ranges were all precision screening strategies, and higher model sensitivities were adopted as WTP increased. Conclusions: Precision screening strategy for esophageal cancer based on risk stratification is more cost-effective than use of traditional screening strategy and has practical implications for esophageal cancer screening programs in China.

7.
Front Oncol ; 12: 849368, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35387122

RESUMEN

Objectives: Upper gastrointestinal (G.I.) cancer screening has been conducted in China for decades. However, the economic burden for treatment "intensively" occurred in advance due to screening in resource-limited communities remain unclear. Methods: We compared the treatment costs for upper G.I. cancers from the screening and control arms of a population-based randomized trial in a high-risk area for esophageal cancer (EC) in China based on claims data from the health insurance system in the local area which included whole population coverage. Results: The average out-of-pocket cost per treatment of EC in the screening arm was lower than that in the control arm ($5,972 vs. $7,557). This difference was a consequence of down-staging from screening which resulted in lower cost therapy for earlier stage cancers. Moreover, this result is similar for cardial and non-cardial gastric cancer in the two study arms ($7,933 vs. $10,605). However, three times as many (103 vs. 36) families in the screening arm suffered catastrophic health expenditure for all cancer types. The overall treatment cost for all EC patients in the screening arm ($1,045,119) was 2.44 times that in the control arm ($428,292), and the ratio for cardial and non-cardial gastric cancer was 1.12 ($393,261 vs. $351,557). Conclusion: Cancer treatment secondary to screening may triple the likelihood of catastrophic patient medical expenditure, and sharply increase the economic pressure on the local community, particularly for cancer types which are of high prevalence. Financial support for patients and the health insurance system should be taken into consideration when planning budgets for cancer screening programs in communities which are resource-limited.

8.
China CDC Wkly ; 4(50): 1131-1135, 2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36751557

RESUMEN

What is already known about this topic?: After the initial coronavirus disease 2019 (COVID-19) outbreak in Wuhan, China, the outbreaks during the dynamic-zero policy period in the mainland of China have not been systematically documented. What is added by this report?: We summarized the characteristics of 74 imported COVID-19 outbreaks between March 19, 2020 and December 31, 2021. All outbreaks of early severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants were successfully contained with the aid of nucleic acid testing, modern communication technologies, and non-pharmacological interventions. What are the implications for public health practice?: These findings provide us with confidence for the containment of future emerging infectious diseases alike at early stages to prevent pandemics or to win time to gain experience, develop vaccines and drugs, vaccinate people, and wait for the possible lessening of the virus' pathogenicity.

9.
China CDC Wkly ; 4(52): 1176-1180, 2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-36779170

RESUMEN

What is already known about this topic?: During the coronavirus disease 2019 (COVID-19) pandemic, tremendous efforts have been made in countries to suppress epidemic peaks and strengthen hospital services to avoid hospital strain and ultimately reduce the risk of death from COVID-19. However, there is limited empirical evidence that hospital strain increases COVID-19 deaths. What is added by this report?: We found the risk of death from COVID-19 was linearly associated with the number of patients currently in hospitals, a measure of hospital strain, before the Omicron period. This risk could be increased by a maximum of 188.0%. What are the implications for public health practice?: These findings suggest that any (additional) effort to reduce hospital strain would be beneficial during early large COVID-19 outbreaks and possibly also others alike. During an Omicron outbreak, vigilance remains necessary to prevent excess deaths caused by hospital strain as happened in Hong Kong Special Administrative Region, China.

10.
PLoS One ; 16(8): e0256128, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34398909

RESUMEN

Change-point detection in health care data has recently obtained considerable attention due to the increased availability of complex data in real-time. In many applications, the observed data is an ordinal time series. Two kinds of test statistics are proposed to detect the structural change of cumulative logistic regression model, which is often used in applications for the analysis of ordinal time series. One is the standardized efficient score vector, the other one is the quadratic form of the efficient score vector with a weight function. Under the null hypothesis, we derive the asymptotic distribution of the two test statistics, and prove the consistency under the alternative hypothesis. We also study the consistency of the change-point estimator, and a binary segmentation procedure is suggested for estimating the locations of possible multiple change-points. Simulation results show that the former statistic performs better when the change-point occurs at the centre of the data, but the latter is preferable when the change-point occurs at the beginning or end of the data. Furthermore, the former statistic could find the reason for rejecting the null hypothesis. Finally, we apply the two test statistics to a group of sleep data, the results show that there exists a structural change in the data.


Asunto(s)
Reconocimiento de Normas Patrones Automatizadas/métodos , Polisomnografía/métodos , Sueño/fisiología , Algoritmos , Simulación por Computador , Interpretación Estadística de Datos , Humanos , Modelos Biológicos , Factores de Tiempo
11.
Pharmacoeconomics ; 37(6): 819-827, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30809788

RESUMEN

BACKGROUND AND OBJECTIVE: Population-level endoscopic screening for esophageal cancer has been conducted in China for years. In this study, we aim to provide an updated and precise cost estimation for esophageal cancer screening based on a randomized controlled trial in a high-risk area in China. METHODS: We estimated the cost of esophageal cancer screening with chromoendoscopy using a micro-costing approach based on primary data of the ESECC (Endoscopic Screening for Esophageal Cancer in China) randomized controlled trial (NCT01688908) from a health sector perspective. Unit costs and quantities of resources were collected to obtain annual screening costs. The screening project was then theoretically expanded to a 10-year period to explore long-term trends of costs. Costs were adjusted to US dollars for the year 2018. RESULTS: In the ESECC trial, screening cost per endoscopy with a valid pathologic diagnosis was $196, accounting for 3.82% of the gross domestic product per capita in Hua County, and the costs for detecting one esophageal cancer and one early-stage esophageal cancer were $26,347 and $37,687, respectively. In conventional screening in which protocol-driven costs were excluded, costs as above were $134, $18,074, and $25,853. The cost for detecting one gastric cardia cancer or stomach cancer was nine times higher than detecting one esophageal cancer owing to low prevalences of the two cancers. In a simulated 10-year screening project, annual cost decreased notably over time. CONCLUSIONS: Despite the relatively low absolute cost, population-level endoscopic screening will still be a heavy burden on local government considering the socioeconomic conditions. Long-lasting programs would be less costly and population-level screening would make little sense in non-high-risk regions.


Asunto(s)
Detección Precoz del Cáncer/economía , Neoplasias Esofágicas/diagnóstico , Esofagoscopía/economía , Costos de la Atención en Salud , Anciano , Humanos , Persona de Mediana Edad
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