Using factorial mediation analysis to better understand the effects of interventions

Author(s):  
Jillian C Strayhorn ◽  
Linda M Collins ◽  
Timothy R Brick ◽  
Sara H Marchese ◽  
Angela Fidler Pfammatter ◽  
...  

Abstract To improve understanding of how interventions work or why they do not work, there is need for methods of testing hypotheses about the causal mechanisms underlying the individual and combined effects of the components that make up interventions. Factorial mediation analysis, i.e., mediation analysis applied to data from a factorial optimization trial, enables testing such hypotheses. In this commentary, we demonstrate how factorial mediation analysis can contribute detailed information about an intervention’s causal mechanisms. We briefly review the multiphase optimization strategy (MOST) and the factorial experiment. We use an empirical example from a 25 factorial optimization trial to demonstrate how factorial mediation analysis opens possibilities for better understanding the individual and combined effects of intervention components. Factorial mediation analysis has important potential to advance theory about interventions and to inform intervention improvements.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pi-Hsia Lee ◽  
Ting-Ting Yeh ◽  
Hsin-Yen Yen ◽  
Wan-Ling Hsu ◽  
Valeria Jia-Yi Chiu ◽  
...  

AbstractStroke and cognitive impairment are common in older population. They often occur together and their combined effects significantly increase disability in both basic (BADLs) and instrumental (IADLs) activities of daily living. We investigated the individual and combined impacts of stroke and cognitive impairment on BADLs and IADLs. A total of 3331 community-dwelling older adults were enrolled from the Taiwan longitudinal study on aging in 2011. Both BADLs and IADLs were analyzed. Combination of stroke and cognitive impairment increased severity of ADL disabilities, but similar prevalence, similar numbers of summed BADL and IADL tasks with disability, and similar levels of difficulty for each BADL and IADL task were found between the stroke group and cognitive impairment group. The former had more difficult in dressing while the latter had more difficult in using the telephone, transport, and managing finances. A hierarchy of ADLs was also observed in all groups. ADL skill training supplemented with cognitive and physical interventions should focus on secondary prevention of dementia and improve motor functional capacity to reduce loss of ADLs.


1989 ◽  
Vol 19 (4) ◽  
pp. 395-415 ◽  
Author(s):  
Jan H. Spyridakis

This study investigated the role of signaling in helping good readers comprehend expository text. As the existing literature on signaling, reviewed in the last issue of this Journal, pointed to deficiencies in previous studies' methodologies, one goal of this study was to refine prose research methods. Two passages were designed in one of eight signaled versions each. The design was constructed to assess the individual and combined effects of headings, previews, and logical connectives. The study also assessed the effect of passage length, familiarity, and difficulty. The results showed that signals do improve a reader's comprehension, particularly comprehension two weeks after the reading of a passage and comprehension of superordinate and superordinate inferential information. This study supports the hypothesis that signals can influence retention of text-based information, particularly with long, unfamiliar, or difficult passages.


2021 ◽  
Vol 22 (12) ◽  
pp. 6281
Author(s):  
Adrienn Balázs ◽  
Zelma Faisal ◽  
Rita Csepregi ◽  
Tamás Kőszegi ◽  
Balázs Kriszt ◽  
...  

Mycotoxins are toxic metabolites of filamentous fungi. Previous studies demonstrated the co-occurrence of Fusarium and Alternaria toxins, including zearalenone (ZEN), ZEN metabolites, and alternariol (AOH). These xenoestrogenic mycotoxins appear in soy-based meals and dietary supplements, resulting in the co-exposure to ZEN and AOH with the phytoestrogen genistein (GEN). In this study, the cytotoxic and estrogenic effects of ZEN, reduced ZEN metabolites, AOH, and GEN are examined to evaluate their individual and combined impacts. Our results demonstrate that reduced ZEN metabolites, AOH, and GEN can aggravate ZEN-induced toxicity; in addition, the compounds tested exerted mostly synergism or additive combined effects regarding cytotoxicity and/or estrogenicity. Therefore, these observations underline the importance and the considerable risk of mycotoxin co-exposure and the combined effects of mycoestrogens with phytoestrogens.


2013 ◽  
Vol 9 (1) ◽  
Author(s):  
Dalton Lopes Martins ◽  
Sueli Mara Soares Pinto Ferreira

Resumo O entendimento das causas e as principais razões que influenciam o modo como os pesquisadores se articulam e constroem suas redes de colaboração científica ainda é uma questão em aberto na pesquisa acadêmica. De fundamental importância para o desenvolvimento de novos indicadores e modos de avaliação da produção científica, o conceito de redes sociais permite operar novos planos de análise, contribuindo com seus aspectos estruturais e dinâmicos ao estudo dos mecanismos e gatilhos causais que levam à constituição dessas redes de colaboração científica. A obtenção de atributos individuais dos pesquisadores, de dados de constituição das redes ao longo do tempo e o modo de desambiguação dos nomes que compõem essas redes de colaboração têm se mostrado os principais desafios de estudos das redes. O objetivo deste artigo é descrever como concebemos uma maneira de estudar as redes de colaboração de uma universidade, com foco específico na Universidade de São Paulo, identificando suas principais estratégias de conectividade e mecanismos causais, além de encontrar as relações entre suas redes e diferentes níveis de produtividade científica de seus participantes. Vale frisar que o artigo apenas descreve as questões da pesquisa e o modo de tratá-las, ficando sua execução para os próximos passos deste trabalho de pesquisa. Para tanto, pretende utilizar como base de análise uma Biblioteca de Produção Científica Institucional em desenvolvimento pelo SiBi/USP, que coleta os artigos publicados por membros da universidade em bases de dados de indexação de revistas nacionais e internacionais, tais como Scielo, Web of Science e BioMed, além da utilização da base de dados institucional para obtenção dos atributos individuais dos pesquisadores participantes dessas redes de colaboração.Palavras-chave análise de redes sociais, indicadores, cientometria, modelos causais.Abstract The understanding of the causes that influence how researchers articulate and build their scientific collaboration networks is still an open question in academic research. Of fundamental importance for the development of new indicators and methods of evaluation of scientific literature, the concept of social networking helps operate new levels of analysis, contributing their structural and dynamic aspects to the study of causal mechanisms and triggers that lead to the formation of these networks of scientific collaboration. Obtaining attributes of individual researchers, data on the constitution of networks over time and mode of disambiguation of the names that make up these collaboration networks have been the main challenges in the area of research networks. The purpose of this article is to describe how we designed a way to study a university’s collaboration networks, focusing on the University of São Paulo, and identifying their key strategies, connectivity and causal mechanisms, as well as finding links between their networks and different levels of participants’ productivity. It should be noted that this article only describes the research questions and how to treat them, leaving their implementation to the next steps of this research. The database used for analysis was the Institutional Scientific Production being developed by Sibi/USP, which collects articles published by members of the university indexed in national and international databases such as Scielo, Web of Science and BioMed, as well as an institutional database to obtain the individual attributes of the researchers participating in these networks.Keywords social network analysis, indicators, scientometrics, causal model


2021 ◽  
pp. 106573
Author(s):  
Evan M. Forman ◽  
Christina Chwyl ◽  
Michael P. Berry ◽  
Lauren C. Taylor ◽  
Meghan L. Butryn ◽  
...  

2020 ◽  
Author(s):  
Jonathan A. Mitchell ◽  
Knashawn H. Morales ◽  
Ariel A. Williamson ◽  
Nicholas Huffnagle ◽  
Casey Eck ◽  
...  

AbstractBackgroundPediatricians lack tools to support families at home for the promotion of childhood sleep. We are using the Multiphase Optimization Strategy (MOST) framework to guide the development of a mobile health platform for childhood sleep promotion.PurposeUnder the preparation phase of the MOST framework, to demonstrate feasibility of a mobile health platform towards treating children with insufficient sleep.MethodsChildren aged 10-12y were enrolled (Study #1: N=30; Study #2: N=43). Participants wore a sleep tracker to measure sleep duration. Data were retrieved by a mobile health platform, programmed to send introductory messages during run-in (2 weeks) and goal achievement messages during intervention (7 weeks) periods. In study #1, participants were randomized to control, gain-framed incentive or loss-framed incentive arms. In study #2, participants were randomized to control, loss-framed incentive, normative feedback or loss-framed incentive plus normative feedback arms.ResultsIn study #1, 1,514 nights of data were captured (69%) and sleep duration during the intervention was higher by an average of 21 (95% CI: -8, 51) and 34 (95% CI: 7, 61) minutes per night for the gain-framed and loss-framed arms, respectively, compared to controls. In study #2, 2,689 nights of data were captured (81%), with no major differences in average sleep duration between the control and the loss-framed or normative feedback arms.ConclusionWe have developed and deployed a mobile health platform that can capture sleep data and remotely communicate with families. Promising candidate intervention components will be further investigated under the optimization phase of the MOST framework.


2019 ◽  
Vol 107 (4) ◽  
pp. 1970-1981 ◽  
Author(s):  
Gabriella L. Pardee ◽  
Isaac O. Jensen ◽  
David W. Inouye ◽  
Rebecca E. Irwin

Sign in / Sign up

Export Citation Format

Share Document