Biostatistics Commons^™

Trends In The Prevalence And Mortality Of Cognitive Impairment In The United States: Is There Evidence Of A Compression Of Cognitive Morbidity, Kenneth Langa, Eric Larson, Jason Karlawish, David Cutler, Mohammed Kabeto, Scott Kim, Allison Rosen

Jason Karlawish

BACKGROUND: Recent medical, demographic, and social trends might have had an important impact on the cognitive health of older adults. To assess the impact of these multiple trends, we compared the prevalence and 2-year mortality of cognitive impairment (CI) consistent with dementia in the United States in 1993 to 1995 and 2002 to 2004. METHODS: We used data from the Health and Retirement Study (HRS), a nationally representative population-based longitudinal survey of U.S. adults. Individuals aged 70 years or older from the 1993 (N = 7,406) and 2002 (N = 7,104) waves of the HRS were included. CI was determined …

Cluster Randomized Trials And Statistical Power, Stephen A. Lauer, Nicholas G. Reich

Nicholas G Reich

The cluster-randomized trial (CRT) is a common study design in public health research. In situations where dividing a group of individuals into treatment and controls is unethical or impossible, a CRT design maintains the strengths of a randomized study design. By comparing the outcomes of small populations (clusters), we can observe the impacts of interventions on the community as a whole. Public health researchers around the world have utilized CRTs to measure the effect of, for example, de-worming medication on school attendance, financial incentives on doctor absenteeism, and providing chlorine to waterholes. The CRT can be a potent tool, however …

Depicting Estimates Using The Intercept In Meta-Regression Models: The Moving Constant Technique, Blair T. Johnson Dr., Tania B. Huedo-Medina Dr.

Blair T. Johnson

In any scientific discipline, the ability to portray research patterns graphically often aids greatly in interpreting a phenomenon. In part to depict phenomena, the statistics and capabilities of meta-analytic models have grown increasingly sophisticated. Accordingly, this article details how to move the constant in weighted meta-analysis regression models (viz. “meta-regression”) to illuminate the patterns in such models across a range of complexities. Although it is commonly ignored in practice, the constant (or intercept) in such models can be indispensible when it is not relegated to its usual static role. The moving constant technique makes possible estimates and confidence intervals at …

Adaptive Pair-Matching In The Search Trial And Estimation Of The Intervention Effect, Laura Balzer, Maya L. Petersen, Mark J. Van Der Laan

Laura B. Balzer

In randomized trials, pair-matching is an intuitive design strategy to protect study validity and to potentially increase study power. In a common design, candidate units are identified, and their baseline characteristics used to create the best n/2 matched pairs. Within the resulting pairs, the intervention is randomized, and the outcomes measured at the end of follow-up. We consider this design to be adaptive, because the construction of the matched pairs depends on the baseline covariates of all candidate units. As consequence, the observed data cannot be considered as n/2 independent, identically distributed (i.i.d.) pairs of units, as current practice assumes. …

Spatial Epidemiology And Climatic Predictors Of Paediatric Dengue Infections Captured Via Sentinel Site Surveillance, Phnom Penh Cambodia 2011–2012, Andrew A. Lover, Philippe Buchy, Anne Rachline, Duch Moniboth, Rekol Huy, Chour Y. Meng, Yee Sin Leo, Kdan Yuvatha, Ung Sophal, Ngan Chantha, Bunthin Y, Veasna Duong, Sophie Goyet, Jeremy Brett, Arnaud Tarantola, Philippe Cavailler

Andrew Lover

Retention And Risk Factors For Attrition In A Large Public Health Art Program In Myanmar: A Retrospective Cohort Analysis, Aye Thida, Sai Thein Than Tun, Sai Ko Ko Zaw, Andrew A. Lover, Philippe Cavailler, Jennifer Chunn, Mar Mar Aye, Par Par, Kyaw Win Naing, Kaung Nyunt Zan, Myint Shwe Shwe, Thar Tun Kyaw, Zaw Htoon Waing, Philippe Clevenbergh

Andrew Lover

Note On The Origin Of The Madagascar Strain Of Plasmodium Vivax, Andrew A. Lover

Andrew Lover

Demographic And Spatial Predictors Of Anemia In Women Of Reproductive Age In Timor-Leste: Implications For Health Program Prioritization, Andrew A. Lover, Mikael Hartman, Kee Seng Chia, David L. Heymann

Andrew Lover

The Distribution Of Incubation And Relapse Times In Experimental Human Infections With The Malaria Parasite Plasmodium Vivax, Andrew A. Lover, Xiahong Zhao, Zheng Gao, Richard J. Coker, Alex R. Cook

Andrew Lover