Dataset Information

Assessment of vibration of effects due to model specification can demonstrate the instability of observational associations.

ABSTRACT:

Objectives

Model specification-what adjusting variables are analytically modeled-may influence results of observational associations. We present a standardized approach to quantify the variability of results obtained with choices of adjustments called the "vibration of effects" (VoE).

Study design and setting

We estimated the VoE for 417 clinical, environmental, and physiological variables in association with all-cause mortality using National Health and Nutrition Examination Survey data. We selected 13 variables as adjustment covariates and computed 8,192 Cox models for each of 417 variables' associations with all-cause mortality.

Results

We present the VoE by assessing the variance of the effect size and in the -log10(P-value) obtained by different combinations of adjustments. We present whether there are multimodality patterns in effect sizes and P-values and the trajectory of results with increasing adjustments. For 31% of the 417 variables, we observed a Janus effect, with the effect being in opposite direction in the 99th versus the 1st percentile of analyses. For example, the vitamin E variant α-tocopherol had a VoE that indicated higher and lower risk for mortality.

Conclusion

Estimating VoE offers empirical estimates of associations are under different model specifications. When VoE is large, claims for observational associations should be very cautious.

SUBMITTER: Patel CJ

PROVIDER: S-EPMC4555355 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Publications

Assessment of vibration of effects due to model specification can demonstrate the instability of observational associations.

Patel Chirag J CJ Burford Belinda B Ioannidis John P A JP

Journal of clinical epidemiology 20150606 9

<h4>Objectives</h4>Model specification-what adjusting variables are analytically modeled-may influence results of observational associations. We present a standardized approach to quantify the variability of results obtained with choices of adjustments called the "vibration of effects" (VoE).<h4>Study design and setting</h4>We estimated the VoE for 417 clinical, environmental, and physiological variables in association with all-cause mortality using National Health and Nutrition Examination Surv ...[more]

PMID: 26279400

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Dataset Information

Assessment of vibration of effects due to model specification can demonstrate the instability of observational associations.

Objectives

Study design and setting

Results

Conclusion

Publications

Assessment of vibration of effects due to model specification can demonstrate the instability of observational associations.

Similar Datasets

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