| 1. |
|
|
| 2. |
- Terrera, G.M., et al.
(författare)
-
Joint modeling of longitudinal change and survival
- 2011
-
Ingår i: GeroPsych: The Journal of Gerontopsychology and Geriatric Psychiatry. - : Hogrefe Publishing Group. - 1662-9647 .- 1662-971X. ; 24:4, s. 177-185
-
Tidskriftsartikel (refereegranskat)abstract
- Joint longitudinal-survival models are useful when repeated measures and event time data are available and possibly associated. The application of this joint model in aging research is relatively rare, albeit particularly useful, when there is the potential for nonrandom dropout. In this article we illustrate the method and discuss some issues that may arise when fitting joint models of this type. Using prose recall scores from the Swedish OCTO-Twin Longitudinal Study of Aging, we fitted a joint longitudinal-survival model to investigate the association between risk of mortality and individual differences in rates of change in memory. A model describing change in memory scores as following an accelerating decline trajectory and a Weibull survival model was identified as the best fitting. This model adjusted for random effects representing individual variation in initial memory performance and change in rate of decline as linking terms between the longitudinal and survival models. Memory performance and change in rate of memory decline were significant predictors of proximity to death. Joint longitudinal-survival models permit researchers to gain a better understanding of the association between change functions and risk of particular events, such as disease diagnosis or death. Careful consideration of computational issues may be required because of the complexities of joint modeling methodologies. © 2011 by Hogrefe Publishing.
|
|
| 3. |
|
|
| 4. |
- Piccinin, A. M., et al.
(författare)
-
Coordinated analysis of age, sex, and education effects on change in MMSE scores
- 2013
-
Ingår i: The journals of gerontology. Series B, Psychological sciences and social sciences. - : Oxford University Press (OUP). - 1079-5014 .- 1758-5368. ; 68:3, s. 374-390
-
Tidskriftsartikel (refereegranskat)abstract
- We describe and compare the expected performance trajectories of older adults on the Mini-Mental Status Examination (MMSE) across six independent studies from four countries in the context of a collaborative network of longitudinal studies of aging. A coordinated analysis approach is used to compare patterns of change conditional on sample composition differences related to age, sex, and education. Such coordination accelerates evaluation of particular hypotheses. In particular, we focus on the effect of educational attainment on cognitive decline. Regular and Tobit mixed models were fit to MMSE scores from each study separately. The effects of age, sex, and education were examined based on more than one centering point. Findings were relatively consistent across studies. On average, MMSE scores were lower for older individuals and declined over time. Education predicted MMSE score, but, with two exceptions, was not associated with decline in MMSE over time. A straightforward association between educational attainment and rate of cognitive decline was not supported. Thoughtful consideration is needed when synthesizing evidence across studies, as methodologies adopted and sample characteristics, such as educational attainment, invariably differ.
|
|
