|
50% attrition rate
| |
70% attrition rate
| |
---|
Dependency (bdrop)
|
bpred(SE)
|
Coverage of 95% C.I.
|
Diff
|
bpred(SE)
|
Coverage of 95% C.I.
|
Diff
|
---|
Pred.
|
V1
|
V2
| | | | | | |
---|
0
|
0
|
0
|
.10 (.04)
|
96%
|
0.00
|
.10 (.05)
|
96%
|
0.00
|
.3
|
.3
|
0
|
.13 (.04)
|
86%
|
0.08
|
.13 (.05)
|
91%
|
0.11
|
.3
|
.3
|
.1
|
.12 (.04)
|
90%
|
0.04
|
.13 (.05)
|
92%
|
0.06
|
.3
|
.3
|
.3
|
.10 (.04)
|
94%
|
-0.02
|
.10 (.06)
|
93%
|
-0.03
|
- 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. Diff = estimated change score (follow-up health minus baseline health). bpred, SE, and Diff 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.
- The true population value was bpred = .10.