Randomization
Attrition
Random-effects
Correlation
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Type of randomization
Type of test
Subject-level
1-sided
Center-level
2-sided
Number of timepoints:
(2 - 20)
Alpha level:
0.01
0.05
0.10
0.50
0.55
0.60
0.65
0.70
0.75
0.80
0.85
0.90
0.95
Number of centers:
(>= 1)
Power level:
0.01
0.05
0.10
0.50
0.55
0.60
0.65
0.70
0.75
0.80
0.85
0.90
0.95
Proportion of Subjects in Group 1:
(0.1 - 0.9)
(0.5 means equal N/grp)
Account for attrition over time
Attrition rates between timepoints
1-2:
2-3:
3-4:
4-5:
5-6:
6-7:
7-8:
8-9:
9-10:
10-11:
11-12:
12-13:
13-14:
14-15:
15-16:
16-17:
17-18:
18-19:
19-20:
Type of mean
Design matrix column 2
Mean difference at last timepoint
Treatment by time interaction
Computed effect size at last timepoint:
Person-level covariance matrix
1,1
2,1
2,2
Center-level covariance matrix
1,1
2,1
2,2
1,2
2,2
3,2
4,2
5,2
6,2
7,2
8,2
9,2
10,2
11,2
12,2
13,2
14,2
15,2
16,2
17,2
18,2
19,2
20,2
Correlation structure of errors
Error variance:
all correlations equal
stationary AR1
toeplitz (banded) matrix
# of correlated lags
Correlation terms
1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
