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Table 1 Estimated associations between baseline predictor and change in health from appropriate use of MR analyses (i.e. in situations where RTM was assumed to occur), as shown in Figure 2

From: Bias in the study of prediction of change: a Monte Carlo simulation study of the effects of selective attrition and inappropriate modeling of regression toward the mean

  50% attrition rate 70% attrition rate
Dependency (bdrop) bpred(SE) Coverage of 95% C.I. bpred(SE) Coverage of 95% C.I.
Pred. V1 V2     
0 0 0 .10 (.04) 95% .10 (.05) 95%
.3 .3 0 .10 (.04) 95% .10 (.05) 93%
.3 .3 .1 .09 (.04) 91% .08 (.05) 93%
.3 .3 .3 .04 (.04) 67% .03 (.05) 73%
  1. Dependency is the magnitude (bdrop) of the regression of liability of dropping out on each of the three study variables. Pred = baseline predictor. V1 = the main variable at baseline (baseline health), V2 = the main variable at follow-up (follow-up health). SE = standard error. bpred = regression coefficient from predictor to change in health. Coverage of 95% C.I. = the percentage of the 500 samples with an estimated bpred with a 95% confidence interval containing the true population value. bpred and SE are average results over the 500 generated samples. N in the original samples was 1000. The first line shows results when attrition was completely random.
  2. The true population value was bpred = .10.