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Table 3 Simulation results comparing analyses with multiple imputation or single midpoint imputation in terms of bias, coverage probability and relative efficiency

From: Simple parametric survival analysis with anonymized register data: A cohort study with truncated and interval censored event and censoring times

    

1 month

2 months

6 months

12 months

Parameter

Censoring

Estimation

n

RB

Cov

SEIF

RB

Cov

SEIF

RB

Cov

SEIF

RB

Cov

SEIF

log(λ)

3%

MC

500

3.0

95.5

0.8

-3.2

94.9

1.6

7.8

94.9

6.4

17.7

94.7

16.8

   

1,000

0.0

94.7

0.8

3.5

94.3

1.7

2.6

95.6

6.4

14.5

94.9

16.7

   

10,000

0.4

95.4

0.8

-0.3

94.9

1.7

2.9

95.5

6.4

14.2

91.0

16.8

  

MI

500

3.0

95.5

0.8

-3.4

94.9

1.6

5.7

94.9

6.4

11.1

95.0

16.8

   

1,000

-0.1

94.8

0.8

3.3

94.3

1.7

1.0

95.4

6.4

8.2

94.8

16.7

   

10,000

0.3

95.4

0.8

-0.3

94.9

1.7

1.3

95.6

6.4

8.0

94.0

16.8

 

6%

MC

500

2.3

95.7

0.7

0.6

94.7

1.6

9.4

95.4

6.3

29.6

94.0

16.6

   

1,000

0.4

94.8

0.7

1.2

95.5

1.6

9.1

95.7

6.3

29.6

94.0

16.7

   

10,000

1.1

94.7

0.8

0.7

94.6

1.7

9.0

94.0

6.3

30.7

77.6

16.8

  

MI

500

2.2

95.7

0.7

0.4

94.7

1.6

6.9

95.2

6.3

19.7

94.6

16.8

   

1,000

0.3

94.7

0.7

1.1

95.5

1.6

7.2

95.7

6.3

21.3

94.6

16.9

   

10,000

1.0

94.7

0.8

0.5

94.6

1.7

6.8

95.0

6.4

22.5

85.7

17.0

 

9%

MC

500

0.4

95.4

0.8

-0.9

95.3

1.6

11.1

95.4

6.2

49.7

92.8

16.9

   

1,000

0.6

95.4

0.7

0.9

95.4

1.5

12.2

95.0

6.2

46.7

91.8

16.8

   

10,000

0.7

95.1

0.8

1.5

94.9

1.6

12.2

91.9

6.2

45.7

57.1

16.8

  

MI

500

0.3

95.4

0.8

-0.9

95.4

1.6

8.3

95.4

6.3

39.3

93.8

17.2

   

1,000

0.6

95.4

0.7

0.5

95.4

1.5

9.5

95.1

6.3

35.9

93.3

17.1

   

10,000

0.5

95.1

0.8

1.2

94.8

1.6

9.4

93.4

6.3

34.9

73.7

17.1

γ

3%

MC

500

0.6

95.0

2.0

1.0

94.8

4.1

3.9

94.5

13.5

7.6

94.8

30.2

   

1,000

0.8

95.4

2.1

2.1

95.1

4.4

1.6

95.0

13.6

6.9

95.0

30.3

   

10,000

-0.2

95.3

2.0

0.5

95.1

4.2

1.6

94.9

13.6

6.0

90.7

30.3

  

MI

500

0.4

94.8

2.0

0.9

94.8

4.1

2.0

94.5

13.4

2.6

94.8

29.8

   

1,000

0.6

95.4

2.1

2.0

95.0

4.4

-0.0

94.8

13.5

2.1

95.0

29.9

   

10,000

-0.4

95.2

2.0

0.4

95.2

4.2

-0.1

95.1

13.4

1.2

94.4

29.8

 

6%

MC

500

2.4

95.7

2.0

1.7

94.6

4.1

6.4

94.8

14.1

12.8

94.1

31.6

   

1,000

-0.4

95.5

2.0

1.8

95.4

4.4

4.5

94.6

14.1

13.3

93.9

31.8

   

10,000

0.1

94.3

2.2

0.7

94.6

4.5

3.7

92.9

14.3

12.8

79.8

31.9

  

MI

500

2.2

95.6

2.0

1.5

94.6

4.1

4.1

94.9

14.0

6.8

94.4

31.3

   

1,000

-0.6

95.5

1.9

1.7

95.4

4.5

2.6

94.4

14.1

7.3

94.8

31.6

   

10,000

-0.0

94.2

2.2

0.6

94.6

4.5

1.8

94.2

14.2

6.8

91.3

31.7

 

9%

MC

500

3.9

95.6

2.6

3.0

95.7

4.7

6.1

95.4

15.2

20.3

92.4

33.8

   

1,000

1.9

95.5

2.2

1.8

94.4

4.7

7.2

95.4

15.0

21.0

92.3

33.6

   

10,000

-0.1

95.5

2.3

1.1

95.0

4.7

5.4

92.4

15.0

20.6

57.1

33.6

  

MI

500

3.7

95.6

2.6

2.8

95.7

4.7

3.5

95.6

15.2

12.9

93.5

33.7

   

1,000

1.7

95.6

2.2

1.6

94.4

4.7

4.8

95.4

15.0

13.3

94.6

33.5

   

10,000

-0.3

95.4

2.3

0.9

95.2

4.7

3.2

94.2

15.0

12.9

80.4

33.5

  1. Simulation results for estimation of log(λ) and γ from datasets with Weibull distributed event times, constant censoring rates, ten years of follow-up, and varying widths of interval censorings. Results for each setting represent analyses of 2,500 generated datasets. Column headers in months indicate width of intervals inducing interval censoring; censoring refers to annual proportion of censoring; Estimation refers to estimation procedure: MC to single imputation of midpoint for censoring events (Equation 5) MI to multiple imputation, (Equation 4). RB is median relative bias in percent, Cov is coverage probability of nominal 95% confidence intervals, while SEIF is percent increase in median standard error relative to analysis with ordinary censoring, but no interval censoring.