ArticleStatistical methods in medical research2018
Sigmoidal mixed models for longitudinal data.
Article in Statistical methods in medical research, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 1 of them a synthesis that pooled it.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
13 citing papers in PubMed, 1 synthesis or guideline pooled it.
- When does cognitive decline begin? A systematic review of change point studies on accelerated decline in cognitive and neurological outcomes preceding mild cognitive impairment, dementia, and death.Psychology and aging · 2018Pooled it
- The dynamics of cognitive decline toward Alzheimer's disease progression: Results from ADSP-PHC's harmonized cognitive composites.Alzheimer's & dementia : the journal of the Alzheimer's Association · 2025Article
- Brain Insulin Signaling is Associated with Late-Life Cognitive Decline.Aging and disease · 2024Article
- nlive: an R package to facilitate the application of the sigmoidal and random changepoint mixed models.BMC medical research methodology · 2023Article
- Brain β-Amyloid Links the Association of Change in Body Mass Index With Cognitive Decline in Community-Dwelling Older Adults.The journals of gerontology. Series A, Biological sciences and medical sciences · 2023Article
- Body Mass Index, Waist Circumference, and Cognitive Decline Among Chinese Older Adults: A Nationwide Retrospective Cohort Study.Frontiers in aging neuroscience · 2022Article
- Influence of Subject-Specific Effects in Longitudinal Modelling of Cognitive Decline in Alzheimer's Disease.Journal of Alzheimer's disease : JAD · 2022Article
- Changes in Body Mass Index Are Related to Faster Cognitive Decline Among African American Older Adults.Journal of the American Geriatrics Society · 2020Article
- Association of Low Systolic Blood Pressure with Postmortem Amyloid-β and Tau.Journal of Alzheimer's disease : JAD · 2020Article
- Time-to-event data with time-varying biomarkers measured only at study entry, with applications to Alzheimer's disease.Statistics in medicine · 2018Article
- Body Mass Index and Decline in Cognitive Function in Older Black and White Persons.The journals of gerontology. Series A, Biological sciences and medical sciences · 2018Article
- Religious Orders Study and Rush Memory and Aging Project.Journal of Alzheimer's disease : JAD · 2018Review
- Hierarchical Bayesian estimation of motor-evoked potential recruitment curves yields accurate and robust estimates.Brain stimulationArticle
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Authors and funding
6 authors.
Funding
Abstract
Linear mixed models are widely used to analyze longitudinal cognitive data. Often, however, the trajectory of cognitive function is nonlinear. For example, some participants may experience cognitive decline that accelerates as death approaches. Polynomial regression and piecewise linear models are common approaches used to characterize nonlinear trajectories, although both have assumptions that may not correspond with the actual trajectories. An alternative is to use a flexible sigmoidal mixed model based on the logistic family of curves. We describe a general class of such a model, which has up to five parameters, representing (1) final level, (2) rate of decline, (3) midpoint of decline, (4) initial level before decline, and (5) asymmetry. Focusing on a four-parameter symmetric sub-class of the model, with random effects on two of the parameters, we demonstrate that a likelihood approach to fitting this model produces accurate estimates of mean levels across time, even in the case of model misspecification. We also illustrate the method on deceased participants who had completed at least 5 years of annual cognitive testing and annual assessment of body mass. We show that departures from a stable body can modify the trajectory curves and anticipate cognitive decline.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.