Comparison of Standardization Methods for the Harmonization of Phenotype Data: An Application to Cognitive Measures.

Comparison of Standardization Methods for the Harmonization of Phenotype Data: An Application to Cognitive Measures.
Am J Epidemiol. 2016 Oct 21;
Authors: Griffith LE, van den Heuvel E, Raina P, Fortier I, Sohel N, Hofer SM, Payette H, Wolfson C, Belleville S, Kenny M, Doiron D
Abstract
Standardization procedures are commonly used to combine phenotype data that were measured using different instruments, but there is little information on how the choice of standardization method influences pooled estimates and heterogeneity. Heterogeneity is of key importance in meta-analyses of observational studies because it affects the statistical models used and the decision of whether or not it is appropriate to calculate a pooled estimate of effect. Using 2-stage individual participant data analyses, we compared 2 common methods of standardization, T-scores and category-centered scores, to create combinable memory scores using cross-sectional data from 3 Canadian population-based studies (the Canadian Study on Health and Aging (1991-1992), the Canadian Community Health Survey on Healthy Aging (2008-2009), and the Quebec Longitudinal Study on Nutrition and Aging (2004-2005)). A simulation was then conducted to assess the influence of varying the following items across population-based studies: 1) effect size, 2) distribution of confounders, and 3) the relationship between confounders and the outcome. We found that pooled estimates based on the u...

Source: Am J Epidemiol - October 20, 2016 Category: Epidemiology Authors: Griffith LE, van den Heuvel E, Raina P, Fortier I, Sohel N, Hofer SM, Payette H, Wolfson C, Belleville S, Kenny M, Doiron D Tags: Am J Epidemiol Source Type: research