scholarly journals Reproducibility of A Posteriori Dietary Patterns across Time and Studies: A Scoping Review

2020 ◽  
Vol 11 (5) ◽  
pp. 1255-1281 ◽  
Author(s):  
Valeria Edefonti ◽  
Roberta De Vito ◽  
Andrea Salvatori ◽  
Francesca Bravi ◽  
Linia Patel ◽  
...  
Keyword(s):  
Statistical Model ◽  
Statistical Methods ◽  
Scoping Review ◽  
Dietary Patterns ◽  
Principal Component ◽  
Systematic Search ◽  
A Posteriori ◽  
Formal Assessment ◽  
Pubmed Database ◽  
Over Time

ABSTRACT Few studies have considered if a posteriori dietary patterns (DPs) are generalizable across different centers or studies, or if they are consistently seen over time. To date, no systematic search of the literature on these topics has been carried out. A scoping review was conducted through a systematic search on the PubMed database. In the current review, we included the 34 articles examining the extent to which a posteriori DPs were consistently seen: 1) across centers from the same study or across different studies potentially representing different populations or countries (here indicated as cross-study reproducibility) and 2) over longer time periods (i.e., ≥2 y) (here indicated as stability over time). Selected articles (published in 1981–2019, 32% from 2010 onwards) were based on observational studies, mostly from Europe and North America. Five articles were based on children and/or adolescents and 14 articles included adults (2 men; 12 women, of whom 3 were pregnant women). A posteriori DPs were mostly derived (32 articles) with principal component or factor analyses. Among the 9 articles assessing DP reproducibility across studies (number of centers/studies: 2–27; median: 3), 5 provided a formal assessment using statistical methods (4 index-based approaches of different complexity, 1 statistical model). A median of 4 DPs was reproduced across centers/studies (range: 1–7). Among the 25 articles assessing DP stability over time (number of time-occasions: 2–6; median: 3), 19 provided a formal assessment with statistical methods (17 index-based and/or test-based approaches, 1 statistical model, 1 with both strategies). The number and composition of DPs remained mostly stable over time. Based on the limited evidence collected, most identified DPs showed good reproducibility across studies and stability over time. However, when present within the single studies, the criteria for the formal assessment of cross-study reproducibility or stability over time were generally very basic.

scholarly journals Sociodemographic and Regional Determinants of Dietary Patterns in Russia

2020 ◽  
Vol 17 (1) ◽  
pp. 328 ◽  
Author(s):  
Sergey Maksimov ◽  
Natalia Karamnova ◽  
Svetlana Shalnova ◽  
Oksana Drapkina
Keyword(s):  
Dietary Patterns ◽  
Age Groups ◽  
Principal Component ◽  
Cross Sectional Study ◽  
Russian Population ◽  
A Posteriori ◽  
Cross Sectional ◽  
Material Wealth ◽  
Face To Face ◽  
Posteriori Analysis

An empirical assessment of diets using a posteriori analysis allows us to define actual dietary patterns (DPs) in the food consumption structure of a population. This study represents an a posteriori assessment of DPs for the Russian population in general as well as their dependence on socio-demographic and regional parameters. The data were obtained from 21,923 individuals aged 25–64 years old from a Russian multicenter study of “Epidemiology of Cardiovascular Diseases in the Regions of the Russian Federation” conducted in 2013–2014. Cross-sectional study subjects were interviewed face-to-face in order to obtain data on their diet. DPs were defined using principal component analysis. Four DPs were specified as “Rational”, “Salt”, “Meat”, and “Mixed”; all these variants together accounted for 55.9% of variance. Diets in gender and age groups corresponded to those for an all-Russian population; in several regions, the defined diets differed from the all-Russian ones. More favorable diet trends were observed among women, people with no family, people not working, and urban dwellers, and diet trends were more favorable with an increase in age, level of education, and material wealth. Thus, a posteriori DPs were defined for the Russian population, which were stable in sex/age groups and were mediated by the socio-demographic characteristics of the population.

scholarly journals Reproducibility and Validity of A Posteriori Dietary Patterns: A Systematic Review

2019 ◽  
Author(s):  
Valeria Edefonti ◽  
Roberta De Vito ◽  
Michela Dalmartello ◽  
Linia Patel ◽  
Andrea Salvatori ◽  
...  
Keyword(s):  
Systematic Review ◽  
Factor Analysis ◽  
Construct Validity ◽  
Dietary Patterns ◽  
Research Question ◽  
A Posteriori ◽  
Food Groups ◽  
Relative Validity ◽  
Pubmed Database ◽  
Statistical Solutions

ABSTRACT The effective use of dietary patterns (DPs) remains limited. There is a need to assess their consistency over multiple administrations of the same dietary source, different dietary sources, or across different studies. Similarly, their generalizability should be based on a previous assessment of DP construct validity. However, to date, no systematic reviews of reproducibility and validity of a posteriori DPs have been carried out. In addition, several methodological questions related to their identification are still open and prevent a fair comparison of epidemiological results on DPs and disease. A systematic review of the literature on the PubMed database was conducted. We identified 218 articles, 64 of which met the inclusion criteria. Of these, the 38 articles dealing with reproducibility and relative and construct validity of DPs were included. These articles (published in 1999–2017, 53% from 2010 onwards) were based on observational studies conducted worldwide. The 14 articles that assessed DP reproducibility across different statistical solutions examined different research questions. Included were: the number of food groups or subjects; input variable format (as well as adjustment for energy intake); algorithms and the number of DPs to retain in cluster analysis; rotation method; and score calculation in factor analysis. However, we identified at most 3 articles per research question on DP reproducibility across statistical solutions. From another 15 articles, reproducibility of DPs over shorter (≤1 y) time periods was generally good and higher than DP relative validity (as measured across different dietary sources). Confirmatory factor analysis was used in 15 of the included articles. It provided reassuring results in identifying valid dietary constructs characterizing the populations under consideration. Based on the available evidence, only suggestive conclusions can be derived on reproducibility across different statistical solutions. Nevertheless, most identified DPs showed good reproducibility, fair relative validity, and good construct validity.

scholarly journals A scoping review of studies using observational data to optimise dynamic treatment regimens

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Robert K. Mahar ◽  
Myra B. McGuinness ◽  
Bibhas Chakraborty ◽  
John B. Carlin ◽  
Maarten J. IJzerman ◽  
...  
Keyword(s):  
Observational Data ◽  
Statistical Methods ◽  
Scoping Review ◽  
Real World ◽  
Inverse Probability Weighting ◽  
Probability Weighting ◽  
Inverse Probability ◽  
Treatment Regimens ◽  
Pubmed Database ◽  
Dynamic Treatment

Abstract Background Dynamic treatment regimens (DTRs) formalise the multi-stage and dynamic decision problems that clinicians often face when treating chronic or progressive medical conditions. Compared to randomised controlled trials, using observational data to optimise DTRs may allow a wider range of treatments to be evaluated at a lower cost. This review aimed to provide an overview of how DTRs are optimised with observational data in practice. Methods Using the PubMed database, a scoping review of studies in which DTRs were optimised using observational data was performed in October 2020. Data extracted from eligible articles included target medical condition, source and type of data, statistical methods, and translational relevance of the included studies. Results From 209 PubMed abstracts, 37 full-text articles were identified, and a further 26 were screened from the reference lists, totalling 63 articles for inclusion in a narrative data synthesis. Observational DTR models are a recent development and their application has been concentrated in a few medical areas, primarily HIV/AIDS (27, 43%), followed by cancer (8, 13%), and diabetes (6, 10%). There was substantial variation in the scope, intent, complexity, and quality between the included studies. Statistical methods that were used included inverse-probability weighting (26, 41%), the parametric G-formula (16, 25%), Q-learning (10, 16%), G-estimation (4, 6%), targeted maximum likelihood/minimum loss-based estimation (4, 6%), regret regression (3, 5%), and other less common approaches (10, 16%). Notably, studies that were primarily intended to address real-world clinical questions (18, 29%) tended to use inverse-probability weighting and the parametric G-formula, relatively well-established methods, along with a large amount of data. Studies focused on methodological developments (45, 71%) tended to be more complicated and included a demonstrative real-world application only. Conclusions As chronic and progressive conditions become more common, the need will grow for personalised treatments and methods to estimate the effects of DTRs. Observational DTR studies will be necessary, but so far their use to inform clinical practice has been limited. Focusing on simple DTRs, collecting large and rich clinical datasets, and fostering tight partnerships between content experts and data analysts may result in more clinically relevant observational DTR studies.

scholarly journals Dietary patterns and nutritional adequacy in a Mediterranean country

2009 ◽  
Vol 101 (S2) ◽  
pp. S21-S28 ◽  
Author(s):  
Lluís Serra-Majem ◽  
Maira Bes-Rastrollo ◽  
Blanca Román-Viñas ◽  
Karina Pfrimer ◽  
Almudena Sánchez-Villegas ◽  
...  
Keyword(s):  
Folic Acid ◽  
Dietary Patterns ◽  
Nutrient Intake ◽  
Principal Component ◽  
Vitamin B ◽  
Mediterranean Country ◽  
A Posteriori ◽  
Diet Patterns ◽  
Study Participants ◽  
Adequate Nutrient

Dietary patterns have been related to health outcomes and morbi-mortality. Mediterranean diet indexes are correlated with adequate nutrient intake. The objective of the present study was to analyse the adequacy of nutrient intake ofa posterioridefined Mediterranean (MDP) and Western (WDP) diet patterns in the Seguimiento Universidad de Navarra (SUN) cohort. A sample of 17 197 subjects participated in the study. Participants completed a 136-item validated semi-quantitative FFQ. Principal component analysis was used to define dietary patterns. Individuals were classified according to quintiles of adherence based on dietary pattern scores. Non-dietary variables, such as smoking and physical activity habits, were also taken into account. The probability approach was used to assess nutrient intake adequacy of certain vitamins (vitamins B12, B6, B3, B2, B1, A, C, D and E) and minerals (Na, Zn, iodine, Se, folic acid, P, Mg, K, Fe and Ca). Logistic regression analysis was used to assess the adequacy of nutrient intake according to adherence to dietary patterns. WDP and MDP were defined. A higher quintile of adherence to an MDP was associated to a lower prevalence of inadequacy for the intake of Zn, iodine, vitamin E, Mg, Fe, vitamin B1, vitamin A, Se, vitamin C and folic acid. The adjusted OR for not reaching at least six (or at least ten) nutrient recommendations were 0·09 (95 % CI: 0·07, 0·11) (and 0·02 (95 % CI: 0·00, 0·16)) for the upper quintile of MDP and 4·4 (95 % CI: 3·6, 5·5) and 2·5 (95 % CI: 1·1, 5·4) for the WDP. The MDP was associated to a better profile of nutrient intake.

scholarly journals Exploration of the Principal Component Analysis (PCA) Approach in Synthesizing the Diet Quality of the Malaysian Population

Nutrients ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 70
Author(s):  
Asma’ Ali ◽  
Barrie M. Margetts ◽  
Ahmad Ali Zainuddin
Keyword(s):  
Principal Component Analysis ◽  
Dietary Patterns ◽  
Dietary Pattern ◽  
Dietary Assessment ◽  
Principal Component ◽  
Positive Association ◽  
Component Analysis ◽  
Peninsular Malaysia ◽  
A Posteriori ◽  
Malaysian Population

(1) Background: One of the most main dietary assessments is through a posteriori application. Although extensive research has incorporated dietary assessment of a population through a posteriori application, this study is the first to examine the Malaysian population and use an a posteriori method and principal component analysis (PCA) to assess the dietary patterns of the Malaysian population. The correlation between all dietary patterns derived via PCA and selected nutrient intake were determined in this sample of study; (2) Methods: A total of 3063 respondents (18 to 59 years old) covering Peninsular Malaysia, Sabah, and Sarawak, participated in this study. PCA was applied on the food frequency questionnaire collected from the respondents, and descriptive statistics and PCA were performed using SPSS version 21; (3) Results: Six patterns were identified: “traditional”, “ prudent”, “ modern”, “western”, “Chinese”, and “combination” diets. All together, these six patterns were able to explain 45.9% of the total variability. Few components derived from the factor loadings showed positive association with several nutrient markers. The traditional dietary pattern showed a moderate, positive correlation with total protein and total sugar intake, there was a significant moderate correlation between the prudent dietary pattern and dietary fibre, and there was a moderate positive association between the Chinese dietary pattern and total energy; and (4) Conclusions: The exploration of the PCA approach above may provide justification for assessment of dietary patterns rather than reliance on single nutrients or foods to identify potential connections to overall nutritional wellbeing as well as to explore the diet–disease relationship. However, study of pattern analysis must be conducted among the Malaysian population to produce validity and reproducibility for this dietary approach in light of the numerous methodological issues that arise when performing PCA.

scholarly journals Tracking of Dietary Patterns From Pregnancy to 6 Years Post-pregnancy in a Multiethnic Asian Cohort: The Growing Up in Singapore Towards Healthy Outcomes (GUSTO) Study

2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 423-423
Author(s):  
Yu Qi Lee ◽  
Marjorelee Colega ◽  
Ray Sugianto ◽  
Jun Shi Lai ◽  
Keith M Godfrey ◽  
...  
Keyword(s):  
Dietary Patterns ◽  
Healthy Lifestyle ◽  
Academic Research ◽  
Correlation Coefficients ◽  
Principal Component ◽  
Weighted Kappa ◽  
Lifestyle Factors ◽  
Poor Correlation ◽  
Physically Active ◽  
Over Time

Abstract Objectives We assessed the stability of maternal dietary patterns from pregnancy to 6 years post-pregnancy and their associated-sociodemographic and lifestyle factors. Methods At 26–28 weeks’ gestation and 6 years post-pregnancy, 24-hour recalls and food frequency questionnaires were collected, respectively, from women in the GUSTO mother-offspring cohort (n = 709). Data on maternal sociodemographic and lifestyle factors were collected at recruitment and again during the 4 to 6-year follow-up visits. Dietary patterns were identified using principal component analysis and stability assessed using Pearson's correlation coefficients and Cohen's weighted kappa. Associations were assessed by multivariable logistic regression, with adjustment for covariates. Results The ‘Fruits, Vegetables and Legumes’ (FVL) and ‘Seafood, Noodle, Soup’ (SNS) patterns were identified at both time points, with poor correlation for the dietary pattern z-scores (correlation coefficients: 0.2 and 0.3, respectively) and modest agreement in tertile assignment (weighted κ: 0.11 and 0.15, respectively), suggesting poor stability. An ‘unhealthy’ pattern was only observed at 6 years post-pregnancy. Women with only primary/secondary level education tended to decrease adherence to FVL pattern over time. Women who had gestational diabetes during pregnancy tended to maintain high adherence to FVL pattern over time. Other health conditions such as hypertension during pregnancy and post-delivery development of type 2 diabetes and hypertension did not appear to influence change in women's diet. Women who showed increased adherence to FVL pattern also exhibited healthy lifestyle behaviours, such as being more physically active, post-pregnancy. Women who adhered more closely to the ‘unhealthy’ pattern at 6 years post-pregnancy tended to be younger, of Malay ethnicity, had lower education, had lower household income at 5 years post-pregnancy, were less physically active and had additional pregnancies. Conclusions Study findings may be used to inform the design of public health interventions for certain subgroups of women during pregnancy and at post-pregnancy that target key dietary and lifestyle risk behaviours. Funding Sources Singapore Ministry of Health's NMRC, Singapore—NMRC/TCR/004-NUS/2008; NMRC/TCR/012-NUHS/2014, SICS, A*STAR, and MOE Academic Research Fund.

Cardiorespiratory fitness is positively associated with both healthy and western dietary pattern in Iranian middle-aged

2020 ◽  
pp. 1-10
Author(s):  
Hossein Shahinfar ◽  
Farhang Djafari ◽  
Nadia Babaei ◽  
Samira Davarzani ◽  
Mojdeh Ebaditabar ◽  
...  
Keyword(s):  
Cardiorespiratory Fitness ◽  
Dietary Patterns ◽  
Dietary Pattern ◽  
Principal Component ◽  
Total Sample ◽  
Linear Regression Models ◽  
Middle Aged ◽  
Anthropometric Measures ◽  
Western Dietary Pattern ◽  
Healthy Dietary Pattern

Abstract. Background: The association between dietary patterns and cardiorespiratory fitness (CRF) is not well established. Objective: We sought to investigate association between a posteriori dietary pattern and CRF in middle-aged adults. Design: Adults (n = 276), aged 20–74 years, who were residents of Tehran, Iran were recruited. Diet was assessed by using a validated 168-item semi-quantitative food frequency questionnaire. Principal component analysis was used to derive dietary patterns. Socio-economic status, anthropometric measures, body composition, and blood pressure were recorded. CRF was assessed by using a graded exercise treadmill test. Analysis of variance and linear regression models were used to discern the association between dietary patterns and CRF. Results: Higher scores of the healthy dietary pattern had no association with VO2max (p = 0.13 ). After controlling for potential confounders, VO2max was positively associated across tertiles of healthy dietary patterns (p < 0.001). Higher adherence to the “mixed” dietary pattern was inversely related to VO2max (p < 0.01). After adjusting for confounders, the significant association disappeared (p = 0.14). Higher scores of the “Western” dietary pattern was not associated with VO2max (p = 0.06). However, after controlling for potential confounders, VO2max was positively associated with the “Western” dietary pattern (p = 0.01). A positive linear association between the “healthy” dietary pattern and CRF for the total sample (R2 = 0.02; p < 0.01) were presented. Conclusions: Overall, our findings suggest that higher adherence to a “healthy” and “Western” dietary pattern was positively associated with CRF. However, further studies are required to examine and clarify the causal relationship between dietary patterns and CRF.

It is better an approximate answer to the right question than the exact answer to the wrong question : the case of the psychometric analysis of the ASQ:SE

2020 ◽  
Author(s):  
Luis Anunciacao ◽  
janet squires ◽  
J. Landeira-Fernandez
Keyword(s):  
Internal Structure ◽  
Statistical Methods ◽  
Principal Component ◽  
Psychological Theory ◽  
Published Data ◽  
Multivariate Statistical ◽  
Exact Answer ◽  
Wide Range ◽  
Ages And Stages Questionnaire ◽  
The Right

One of the main activities in psychometrics is to analyze the internal structure of a test. Multivariate statistical methods, including Exploratory Factor analysis (EFA) and Principal Component Analysis (PCA) are frequently used to do this, but the growth of Network Analysis (NA) places this method as a promising candidate. The results obtained by these methods are of valuable interest, as they not only produce evidence to explore if the test is measuring its intended construct, but also to deal with the substantive theory that motivated the test development. However, these different statistical methods come up with different answers, providing the basis for different analytical and theoretical strategies when one needs to choose a solution. In this study, we took advantage of a large volume of published data (n = 22,331) obtained by the Ages and Stages Questionnaire Social-Emotional (ASQ:SE), and formed a subset of 500 children to present and discuss alternative psychometric solutions to its internal structure, and also to its subjacent theory. The analyses were based on a polychoric matrix, the number of factors to retain followed several well-known rules of thumb, and a wide range of exploratory methods was fitted to the data, including EFA, PCA, and NA. The statistical outcomes were divergent, varying from 1 to 6 domains, allowing a flexible interpretation of the results. We argue that the use of statistical methods in the absence of a well-grounded psychological theory has limited applications, despite its appeal. All data and codes are available at https://osf.io/z6gwv/.

scholarly journals Development of the Statistical Model for Monitoring Salinization in the Mekong Delta of Vietnam Using Remote Sensing Data and In-Situ Measurements

Proceedings ◽  
2018 ◽  
Vol 2 (10) ◽  
pp. 565
Author(s):  
Nguyen Nguyen Vu ◽  
Le Van Trung ◽  
Tran Thi Van
Keyword(s):  
Statistical Model ◽  
Mekong Delta ◽  
Remote Sensing Data ◽  
Principal Component ◽  
Measured Data ◽  
In Situ Measurements ◽  
Landsat 8 ◽  
Spectral Bands ◽  
Component Band

This article presents the methodology for developing a statistical model for monitoring salinity intrusion in the Mekong Delta based on the integration of satellite imagery and in-situ measurements. We used Landsat-8 Operational Land Imager and Thermal Infrared Sensor (Landsat- 8 OLI and TIRS) satellite data to establish the relationship between the planetary reflectance and the ground measured data in the dry season during 2014. The three spectral bands (blue, green, red) and the principal component band were used to obtain the most suitable models. The selected model showed a good correlation with the exponential function of the principal component band and the ground measured data (R2 > 0.8). Simulation of the salinity distribution along the river shows the intrusion of a 4 g/L salt boundary from the estuary to the inner field of more than 50 km. The developed model will be an active contribution, providing managers with adaptation and response solutions suitable for intrusion in the estuary as well as the inner field of the Mekong Delta.

Supporting the Mental Health and Well-Being of First Responders from Career to Retirement: A Scoping Review

2021 ◽  
pp. 1-6
Author(s):  
Erin Smith ◽  
Greg Dean ◽  
Lisa Holmes
Keyword(s):  
Mental Health ◽  
Scoping Review ◽  
Help Seeking ◽  
First Responders ◽  
Well Being ◽  
First Responder ◽  
Help Seeking Behaviors ◽  
Holistic Approaches ◽  
Pubmed Database ◽  
Health And Well Being

Abstract Introduction: First responders are at greater risk of mental ill health and compromised well-being compared to the general population. It is important to identify strategies that will be effective in supporting mental health, both during and after the first responder’s career. Methods: A scoping review was conducted using the PubMed database (1966 to October 1, 2020) and the Google Scholar database (October 1, 2020) using relevant search terms, truncation symbols, and Boolean combination functions. The reference lists of all relevant publications were also reviewed to identify further publications. Results: A total of 172 publications were retrieved by the combined search strategies. Of these, 56 met the inclusion criteria and informed the results of this overview paper. These publications identified that strategies supporting first responder mental health and well-being need to break down stigma and build resilience. Normalizing conversations around mental health is integral for increasing help-seeking behaviors, both during a first responder’s career and in retirement. Organizations should consider the implementation of both pre-retirement and post-retirement support strategies to improve mental health and well-being. Conclusion: Strategies for supporting mental health and well-being need to be implemented early in the first responder career and reinforced throughout and into retirement. They should utilize holistic approaches which encourage “reaching in” rather than placing an onus on first responders to “reach out” when they are in crisis.

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