library(rpact)
packageVersion("rpact") # version should be version 3.0 or later
Defining Accrual Time and Accrual Intensity with rpact
Load the rpact package
[1] '3.3.4'
Case 1
End of accrual, absolute accrual intensity and maxNumberOfSubjects
are given, followUpTime
shall be calculated.
Example: vector based definition
<- getAccrualTime(
accrualTime accrualTime = c(0, 6, 30),
accrualIntensity = c(22, 33), maxNumberOfSubjects = 924
)kable(accrualTime)
Accrual time and intensity
- 0 - < 6: 22
- 6 - <=30: 33
Formula
- maxNumberOfSubjects = 924 = 6 * 22 + 24 * 33
Case (#1)
- End of accrual, absolute accrual intensity and ‘maxNumberOfSubjects’ are given, ‘followUpTime’** shall be calculated.
- Example: getAccrualTime(accrualTime = c(0, 6, 30), accrualIntensity = c(22, 33), maxNumberOfSubjects = 924)
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00, 30.00
- Accrual intensity: 22.0, 33.0
- Maximum number of subjects: 924
Generated parameters
- End of accrual is user defined: TRUE
- Follow-up time must be user defined: FALSE
- Max number of subjects is user defined: TRUE
- Max number of subjects can be calculated directly: TRUE
- Absolute accrual intensity is enabled: TRUE
Example: list based definition
<- getAccrualTime(
accrualTime list(
"0 - <6" = 22,
"6 - <= 30" = 33
),maxNumberOfSubjects = 924
)kable(accrualTime)
Accrual time and intensity
- 0 - < 6: 22
- 6 - <=30: 33
Formula
- maxNumberOfSubjects = 924 = 6 * 22 + 24 * 33
Case (#1)
- End of accrual, absolute accrual intensity and ‘maxNumberOfSubjects’ are given, ‘followUpTime’** shall be calculated.
- Example: getAccrualTime(accrualTime = c(0, 6, 30), accrualIntensity = c(22, 33), maxNumberOfSubjects = 924)
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00, 30.00
- Accrual intensity: 22.0, 33.0
- Maximum number of subjects: 924
Generated parameters
- End of accrual is user defined: TRUE
- Follow-up time must be user defined: FALSE
- Max number of subjects is user defined: TRUE
- Max number of subjects can be calculated directly: TRUE
- Absolute accrual intensity is enabled: TRUE
Example: how to use accrual time object
kable(getSampleSizeSurvival(accrualTime = accrualTime, pi1 = 0.23, pi2 = 0.3))
Design plan parameters and output for survival data
Design parameters
- Critical values: 1.96
- Significance level: 0.0250
- Type II error rate: 0.2000
- Test: one-sided
User defined parameters
- Assumed treatment rate: 0.230
- Assumed control rate: 0.300
- Maximum number of subjects: 924
- Accrual time: 6.00, 30.00
- Accrual intensity: 22.0, 33.0
Default parameters
- Theta H0: 1
- Type of computation: Schoenfeld
- Planned allocation ratio: 1
- Event time: 12
- kappa: 1
- Drop-out rate (1): 0.000
- Drop-out rate (2): 0.000
- Drop-out time: 12.00
Sample size and output
- Direction upper: FALSE
- median(1): 31.8
- median(2): 23.3
- lambda(1): 0.0218
- lambda(2): 0.0297
- Hazard ratio: 0.733
- Number of events: 324.8
- Total accrual time: 30.00
- Follow up time: 3.66
- Number of events fixed: 324.8
- Number of subjects fixed: 924
- Number of subjects fixed (1): 462
- Number of subjects fixed (2): 462
- Analysis times: 33.66
- Study duration: 33.66
- Critical values (treatment effect scale): 0.805
Legend
- (i): values of treatment arm i
Case 2
End of accrual, relative accrual intensity and maxNumberOfSubjects
are given, absolute accrual intensity and followUpTime
shall be calculated.
Example: vector based definition
<- getAccrualTime(
accrualTime accrualTime = c(0, 6, 30),
accrualIntensity = c(0.22, 0.33), maxNumberOfSubjects = 1000
)kable(accrualTime)
Accrual time and intensity
- 0 - < 6: 23.80952
- 6 - <=30: 35.71429
Formula
- maxNumberOfSubjects = 1000 = 6 * 23.8095 + 24 * 35.7143
Case (#2)
- End of accrual, relative accrual intensity and ‘maxNumberOfSubjects’ are given, absolute accrual intensity* and ‘followUpTime’** shall be calculated.
- Example: getAccrualTime(accrualTime = c(0, 6, 30), accrualIntensity = c(0.22, 0.33), maxNumberOfSubjects = 1000)
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00, 30.00
- Accrual intensity (relative): 0.22, 0.33
- Maximum number of subjects: 1000
Generated parameters
- End of accrual is user defined: TRUE
- Follow-up time must be user defined: FALSE
- Max number of subjects is user defined: TRUE
- Max number of subjects can be calculated directly: TRUE
- Absolute accrual intensity is enabled: FALSE
- Accrual intensity: 23.8, 35.7
- Remaining time: 24.00
Example: list based definition
<- getAccrualTime(
accrualTime list(
"0 - <6" = 0.22,
"6 - <= 30" = 0.33
),maxNumberOfSubjects = 1000
)kable(accrualTime)
Accrual time and intensity
- 0 - < 6: 23.80952
- 6 - <=30: 35.71429
Formula
- maxNumberOfSubjects = 1000 = 6 * 23.8095 + 24 * 35.7143
Case (#2)
- End of accrual, relative accrual intensity and ‘maxNumberOfSubjects’ are given, absolute accrual intensity* and ‘followUpTime’** shall be calculated.
- Example: getAccrualTime(accrualTime = c(0, 6, 30), accrualIntensity = c(0.22, 0.33), maxNumberOfSubjects = 1000)
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00, 30.00
- Accrual intensity (relative): 0.22, 0.33
- Maximum number of subjects: 1000
Generated parameters
- End of accrual is user defined: TRUE
- Follow-up time must be user defined: FALSE
- Max number of subjects is user defined: TRUE
- Max number of subjects can be calculated directly: TRUE
- Absolute accrual intensity is enabled: FALSE
- Accrual intensity: 23.8, 35.7
- Remaining time: 24.00
Example: how to use accrual time object
kable(getSampleSizeSurvival(accrualTime = accrualTime, pi1 = 0.23, pi2 = 0.3))
Design plan parameters and output for survival data
Design parameters
- Critical values: 1.96
- Significance level: 0.0250
- Type II error rate: 0.2000
- Test: one-sided
User defined parameters
- Assumed treatment rate: 0.230
- Assumed control rate: 0.300
- Maximum number of subjects: 1000
- Accrual time: 6.00, 30.00
Default parameters
- Theta H0: 1
- Type of computation: Schoenfeld
- Planned allocation ratio: 1
- Event time: 12
- kappa: 1
- Drop-out rate (1): 0.000
- Drop-out rate (2): 0.000
- Drop-out time: 12.00
Sample size and output
- Direction upper: FALSE
- median(1): 31.8
- median(2): 23.3
- lambda(1): 0.0218
- lambda(2): 0.0297
- Hazard ratio: 0.733
- Number of events: 324.8
- Total accrual time: 30.00
- Accrual intensity: 23.8, 35.7
- Follow up time: 2.07
- Number of events fixed: 324.8
- Number of subjects fixed: 1000
- Number of subjects fixed (1): 500
- Number of subjects fixed (2): 500
- Analysis times: 32.07
- Study duration: 32.07
- Critical values (treatment effect scale): 0.805
Legend
- (i): values of treatment arm i
Case 3
End of accrual and absolute accrual intensity are given, maxNumberOfSubjects
and followUpTime
shall be calculated.
Example: vector based definition
<- getAccrualTime(accrualTime = c(0, 6, 30), accrualIntensity = c(22, 33)) accrualTime
Example: list based definition
<- getAccrualTime(list(
accrualTime "0 - <6" = 22,
"6 - <= 30" = 33
))kable(accrualTime)
Accrual time and intensity
- 0 - < 6: 22
- 6 - <=30: 33
Formula
- maxNumberOfSubjects = 924 = 6 * 22 + 24 * 33
Case (#3)
- End of accrual and absolute accrual intensity are given, ‘maxNumberOfSubjects’* and ‘followUpTime’** shall be calculated.
- Example: getAccrualTime(accrualTime = c(0, 6, 30), accrualIntensity = c(22, 33))
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00, 30.00
- Accrual intensity: 22.0, 33.0
Generated parameters
- End of accrual is user defined: TRUE
- Follow-up time must be user defined: FALSE
- Max number of subjects is user defined: FALSE
- Max number of subjects can be calculated directly: TRUE
- Absolute accrual intensity is enabled: TRUE
- Maximum number of subjects: 924
- Remaining time: 24.00
Example: how to use accrual time object
kable(getSampleSizeSurvival(accrualTime = accrualTime, pi1 = 0.23, pi2 = 0.3))
Design plan parameters and output for survival data
Design parameters
- Critical values: 1.96
- Significance level: 0.0250
- Type II error rate: 0.2000
- Test: one-sided
User defined parameters
- Assumed treatment rate: 0.230
- Assumed control rate: 0.300
- Accrual time: 6.00, 30.00
- Accrual intensity: 22.0, 33.0
Default parameters
- Theta H0: 1
- Type of computation: Schoenfeld
- Planned allocation ratio: 1
- Event time: 12
- kappa: 1
- Drop-out rate (1): 0.000
- Drop-out rate (2): 0.000
- Drop-out time: 12.00
Sample size and output
- Direction upper: FALSE
- median(1): 31.8
- median(2): 23.3
- lambda(1): 0.0218
- lambda(2): 0.0297
- Hazard ratio: 0.733
- Maximum number of subjects: 924
- Number of events: 324.8
- Total accrual time: 30.00
- Follow up time: 3.66
- Number of events fixed: 324.8
- Number of subjects fixed: 924
- Number of subjects fixed (1): 462
- Number of subjects fixed (2): 462
- Analysis times: 33.66
- Study duration: 33.66
- Critical values (treatment effect scale): 0.805
Legend
- (i): values of treatment arm i
Case 4
End of accrual, relative accrual intensity and followUpTime
are given, absolute accrual intensity and maxNumberOfSubjects
shall be calculated.
Example: vector based definition
<- getAccrualTime(accrualTime = c(0, 6, 30), accrualIntensity = c(0.22, 0.33))
accrualTime kable(accrualTime)
Accrual time and intensity
- 0 - < 6: 0.22
- 6 - <=30: 0.33
Formula
- maxNumberOfSubjects = 6 * 0.22 * c + 24 * 0.33 * c , where ‘c’ is a constant factor
Case (#4)
- End of accrual, relative accrual intensity and ‘followUpTime’ are given, absolute accrual intensity** and ‘maxNumberOfSubjects’** shall be calculated.
- Example: getAccrualTime(accrualTime = c(0, 6, 30), accrualIntensity = c(0.22, 0.33))
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00, 30.00
- Accrual intensity: 0.22, 0.33
Generated parameters
- End of accrual is user defined: TRUE
- Follow-up time must be user defined: FALSE
- Max number of subjects is user defined: FALSE
- Max number of subjects can be calculated directly: FALSE
- Absolute accrual intensity is enabled: FALSE
Example: list based definition
<- getAccrualTime(list(
accrualTime "0 - <6" = 0.22,
"6 - <= 30" = 0.33
))kable(accrualTime)
Accrual time and intensity
- 0 - < 6: 0.22
- 6 - <=30: 0.33
Formula
- maxNumberOfSubjects = 6 * 0.22 * c + 24 * 0.33 * c , where ‘c’ is a constant factor
Case (#4)
- End of accrual, relative accrual intensity and ‘followUpTime’ are given, absolute accrual intensity** and ‘maxNumberOfSubjects’** shall be calculated.
- Example: getAccrualTime(accrualTime = c(0, 6, 30), accrualIntensity = c(0.22, 0.33))
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00, 30.00
- Accrual intensity: 0.22, 0.33
Generated parameters
- End of accrual is user defined: TRUE
- Follow-up time must be user defined: FALSE
- Max number of subjects is user defined: FALSE
- Max number of subjects can be calculated directly: FALSE
- Absolute accrual intensity is enabled: FALSE
Example: how to use accrual time object
kable(getSampleSizeSurvival(accrualTime = accrualTime, pi1 = 0.23, pi2 = 0.3, followUpTime = 6))
Design plan parameters and output for survival data
Design parameters
- Critical values: 1.96
- Significance level: 0.0250
- Type II error rate: 0.2000
- Test: one-sided
User defined parameters
- Assumed treatment rate: 0.230
- Assumed control rate: 0.300
- Accrual time: 6.00, 30.00
Default parameters
- Theta H0: 1
- Type of computation: Schoenfeld
- Planned allocation ratio: 1
- Event time: 12
- kappa: 1
- Follow up time: 6.00
- Drop-out rate (1): 0.000
- Drop-out rate (2): 0.000
- Drop-out time: 12.00
Sample size and output
- Direction upper: FALSE
- median(1): 31.8
- median(2): 23.3
- lambda(1): 0.0218
- lambda(2): 0.0297
- Hazard ratio: 0.733
- Number of events: 324.8
- Total accrual time: 30.00
- Accrual intensity: 139.1, 27.8
- Number of events fixed: 324.8
- Number of subjects fixed: 834.7
- Number of subjects fixed (1): 417.4
- Number of subjects fixed (2): 417.4
- Analysis times: 36.00
- Study duration: 36.00
- Critical values (treatment effect scale): 0.805
Legend
- (i): values of treatment arm i
Case 5
maxNumberOfSubjects
and absolute accrual intensity are given, end of accrual and followUpTime
shall be calculated
Example: vector based definition
<- getAccrualTime(
accrualTime accrualTime = c(0, 6),
accrualIntensity = c(22, 33), maxNumberOfSubjects = 1000
)kable(accrualTime)
Accrual time and intensity
- 0.00000 - < 6.00000: 22
- 6.00000 - <=32.30303: 33
Formula
- maxNumberOfSubjects = 1000 = 6 * 22 + 26.303 * 33
Case (#5)
- ‘maxNumberOfSubjects’ and absolute accrual intensity are given, end of accrual* and ‘followUpTime’** shall be calculated
- Example: getAccrualTime(accrualTime = c(0, 6), accrualIntensity = c(22, 33), maxNumberOfSubjects = 1000)
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00, 32.30
- Accrual intensity: 22.0, 33.0
- Maximum number of subjects: 1000
Generated parameters
- End of accrual is user defined: FALSE
- Follow-up time must be user defined: FALSE
- Max number of subjects is user defined: TRUE
- Max number of subjects can be calculated directly: TRUE
- Absolute accrual intensity is enabled: TRUE
- Remaining time: 26.30
Example: list based definition
<- getAccrualTime(
accrualTime list(
"0 - <6" = 22,
"6" = 33
),maxNumberOfSubjects = 1000
)kable(accrualTime)
Accrual time and intensity
- 0.00000 - < 6.00000: 22
- 6.00000 - <=32.30303: 33
Formula
- maxNumberOfSubjects = 1000 = 6 * 22 + 26.303 * 33
Case (#5)
- ‘maxNumberOfSubjects’ and absolute accrual intensity are given, end of accrual* and ‘followUpTime’** shall be calculated
- Example: getAccrualTime(accrualTime = c(0, 6), accrualIntensity = c(22, 33), maxNumberOfSubjects = 1000)
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00, 32.30
- Accrual intensity: 22.0, 33.0
- Maximum number of subjects: 1000
Generated parameters
- End of accrual is user defined: FALSE
- Follow-up time must be user defined: FALSE
- Max number of subjects is user defined: TRUE
- Max number of subjects can be calculated directly: TRUE
- Absolute accrual intensity is enabled: TRUE
- Remaining time: 26.30
Example: how to use accrual time object
kable(getSampleSizeSurvival(accrualTime = accrualTime, pi1 = 0.23, pi2 = 0.3))
Design plan parameters and output for survival data
Design parameters
- Critical values: 1.96
- Significance level: 0.0250
- Type II error rate: 0.2000
- Test: one-sided
User defined parameters
- Assumed treatment rate: 0.230
- Assumed control rate: 0.300
- Maximum number of subjects: 1000
- Accrual time: 6.00, 32.30
- Accrual intensity: 22.0, 33.0
Default parameters
- Theta H0: 1
- Type of computation: Schoenfeld
- Planned allocation ratio: 1
- Event time: 12
- kappa: 1
- Drop-out rate (1): 0.000
- Drop-out rate (2): 0.000
- Drop-out time: 12.00
Sample size and output
- Direction upper: FALSE
- median(1): 31.8
- median(2): 23.3
- lambda(1): 0.0218
- lambda(2): 0.0297
- Hazard ratio: 0.733
- Number of events: 324.8
- Total accrual time: 32.30
- Follow up time: 1.08
- Number of events fixed: 324.8
- Number of subjects fixed: 1000
- Number of subjects fixed (1): 500
- Number of subjects fixed (2): 500
- Analysis times: 33.38
- Study duration: 33.38
- Critical values (treatment effect scale): 0.805
Legend
- (i): values of treatment arm i
Case 6 (not possible)
maxNumberOfSubjects
and relative accrual intensity are given, absolute accrual intensity[x], end of accrual and followUpTime
shall be calculated
Example: vector based definition
<- getAccrualTime(
accrualTime accrualTime = c(0, 6),
accrualIntensity = c(0.22, 0.33),
maxNumberOfSubjects = 1000
)
Warning: The specified accrual time and intensity cannot be supplemented
automatically with the missing information; therefore further calculations are
not possible
kable(accrualTime)
Accrual time and intensity
- 0 - <=6: 0.22
Formula
- maxNumberOfSubjects = 1000 = 6 * 0.22 * c + (x - 6) * 0.33 * c , where ‘x’ is the unknown last accrual time and ‘c’ a constant factor
Case (#6)
- ‘maxNumberOfSubjects’ and relative accrual intensity are given, absolute accrual intensity@, end of accrual* and ‘followUpTime’** shall be calculated
- Example: getAccrualTime(accrualTime = c(0, 6), accrualIntensity = c(0.22, 0.33), maxNumberOfSubjects = 1000)
- Cannot be calculated.
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00
- Accrual intensity: 0.22, 0.33
- Maximum number of subjects: 1000
Generated parameters
- End of accrual is user defined: FALSE
- Follow-up time must be user defined: FALSE
- Max number of subjects is user defined: TRUE
- Max number of subjects can be calculated directly: TRUE
- Absolute accrual intensity is enabled: FALSE
Example: list based definition
<- getAccrualTime(
accrualTime list(
"0 - <6" = 0.22,
"6" = 0.33
),maxNumberOfSubjects = 1000
)
Warning: The specified accrual time and intensity cannot be supplemented
automatically with the missing information; therefore further calculations are
not possible
kable(accrualTime)
Accrual time and intensity
- 0 - <=6: 0.22
Formula
- maxNumberOfSubjects = 1000 = 6 * 0.22 * c + (x - 6) * 0.33 * c , where ‘x’ is the unknown last accrual time and ‘c’ a constant factor
Case (#6)
- ‘maxNumberOfSubjects’ and relative accrual intensity are given, absolute accrual intensity@, end of accrual* and ‘followUpTime’** shall be calculated
- Example: getAccrualTime(accrualTime = c(0, 6), accrualIntensity = c(0.22, 0.33), maxNumberOfSubjects = 1000)
- Cannot be calculated.
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00
- Accrual intensity: 0.22, 0.33
- Maximum number of subjects: 1000
Generated parameters
- End of accrual is user defined: FALSE
- Follow-up time must be user defined: FALSE
- Max number of subjects is user defined: TRUE
- Max number of subjects can be calculated directly: TRUE
- Absolute accrual intensity is enabled: FALSE
Example: how to use accrual time object
Case 6 is not allowed and therefore an error will be shown:
tryCatch(
{getSampleSizeSurvival(accrualTime = accrualTime, pi1 = 0.23, pi2 = 0.3)
},error = function(e) {
print(e$message)
} )
[1] "Illegal argument: the calculation of 'followUpTime' for given 'maxNumberOfSubjects' and relative accrual intensities (< 1) can only be done if end of accrual is defined"
Case 7
followUpTime
and absolute accrual intensity are given,
end of accrual and maxNumberOfSubjects
shall be calculated
Example: vector based definition
<- getAccrualTime(accrualTime = c(0, 6), accrualIntensity = c(22, 33))
accrualTime kable(accrualTime)
Accrual time and intensity
- 0 - <=6: 22
- 6 - <=[?]: 33
Formula
- maxNumberOfSubjects = 6 * 22 + (x - 6) * 33, where ‘x’ is the unknown last accrual time
Case (#7)
- ‘followUpTime’ and absolute accrual intensity are given, end of accrual** and ‘maxNumberOfSubjects’** shall be calculated
- Example: getAccrualTime(accrualTime = c(0, 6), accrualIntensity = c(22, 33))
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00
- Accrual intensity: 22.0, 33.0
Generated parameters
- End of accrual is user defined: FALSE
- Follow-up time must be user defined: TRUE
- Max number of subjects is user defined: FALSE
- Max number of subjects can be calculated directly: FALSE
- Absolute accrual intensity is enabled: TRUE
Example: list based definition
<- getAccrualTime(list(
accrualTime "0 - <6" = 22,
"6" = 33
))kable(accrualTime)
Accrual time and intensity
- 0 - <=6: 22
- 6 - <=[?]: 33
Formula
- maxNumberOfSubjects = 6 * 22 + (x - 6) * 33, where ‘x’ is the unknown last accrual time
Case (#7)
- ‘followUpTime’ and absolute accrual intensity are given, end of accrual** and ‘maxNumberOfSubjects’** shall be calculated
- Example: getAccrualTime(accrualTime = c(0, 6), accrualIntensity = c(22, 33))
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00
- Accrual intensity: 22.0, 33.0
Generated parameters
- End of accrual is user defined: FALSE
- Follow-up time must be user defined: TRUE
- Max number of subjects is user defined: FALSE
- Max number of subjects can be calculated directly: FALSE
- Absolute accrual intensity is enabled: TRUE
Example: how to use accrual time object
kable(getSampleSizeSurvival(
accrualTime = accrualTime,
pi1 = 0.4, pi2 = 0.2, followUpTime = 6
))
Design plan parameters and output for survival data
Design parameters
- Critical values: 1.96
- Significance level: 0.0250
- Type II error rate: 0.2000
- Test: one-sided
User defined parameters
- Assumed treatment rate: 0.400
- Accrual intensity: 22.0, 33.0
- Follow up time: 6.00
Default parameters
- Theta H0: 1
- Type of computation: Schoenfeld
- Assumed control rate: 0.200
- Planned allocation ratio: 1
- Event time: 12
- kappa: 1
- Drop-out rate (1): 0.000
- Drop-out rate (2): 0.000
- Drop-out time: 12.00
Sample size and output
- Direction upper: TRUE
- median(1): 16.3
- median(2): 37.3
- lambda(1): 0.0426
- lambda(2): 0.0186
- Hazard ratio: 2.289
- Maximum number of subjects: 186.1
- Number of events: 45.8
- Accrual time: 6.00, 7.64
- Total accrual time: 7.64
- Number of events fixed: 45.8
- Number of subjects fixed: 186.1
- Number of subjects fixed (1): 93
- Number of subjects fixed (2): 93
- Analysis times: 13.64
- Study duration: 13.64
- Critical values (treatment effect scale): 1.785
Legend
- (i): values of treatment arm i
Case 8 (not possible)
followUpTime
and relative accrual intensity are given,
absolute accrual intensity[x], end of accrual and maxNumberOfSubjects
shall be calculated
Example: vector based definition
<- getAccrualTime(accrualTime = c(0, 6), accrualIntensity = c(0.22, 0.33)) accrualTime
Warning: The specified accrual time and intensity cannot be supplemented
automatically with the missing information; therefore further calculations are
not possible
kable(accrualTime)
Accrual time and intensity
- 0 - <=6: 0.22
- 6 - <=[?]: 0.33
Formula
- maxNumberOfSubjects = 6 * 0.22 * c + (x - 6) * 0.33 * c , where ‘x’ is the unknown last accrual time and ‘c’ a constant factor
Case (#8)
- ‘followUpTime’ and relative accrual intensity are given, absolute accrual intensity@, end of accrual and ‘maxNumberOfSubjects’ shall be calculated
- Example: getAccrualTime(accrualTime = c(0, 6), accrualIntensity = c(0.22, 0.33))
- Cannot be calculated.
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00
- Accrual intensity: 0.22, 0.33
Generated parameters
- End of accrual is user defined: FALSE
- Follow-up time must be user defined: TRUE
- Max number of subjects is user defined: FALSE
- Max number of subjects can be calculated directly: FALSE
- Absolute accrual intensity is enabled: FALSE
Example: list based definition
<- getAccrualTime(list(
accrualTime "0 - <6" = 0.22,
"6" = 0.33
))
Warning: The specified accrual time and intensity cannot be supplemented
automatically with the missing information; therefore further calculations are
not possible
kable(accrualTime)
Accrual time and intensity
- 0 - <=6: 0.22
- 6 - <=[?]: 0.33
Formula
- maxNumberOfSubjects = 6 * 0.22 * c + (x - 6) * 0.33 * c , where ‘x’ is the unknown last accrual time and ‘c’ a constant factor
Case (#8)
- ‘followUpTime’ and relative accrual intensity are given, absolute accrual intensity@, end of accrual and ‘maxNumberOfSubjects’ shall be calculated
- Example: getAccrualTime(accrualTime = c(0, 6), accrualIntensity = c(0.22, 0.33))
- Cannot be calculated.
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00
- Accrual intensity: 0.22, 0.33
Generated parameters
- End of accrual is user defined: FALSE
- Follow-up time must be user defined: TRUE
- Max number of subjects is user defined: FALSE
- Max number of subjects can be calculated directly: FALSE
- Absolute accrual intensity is enabled: FALSE
Example: how to use accrual time object
Case 8 is not allowed and therefore an error will be shown:
tryCatch(
{getSampleSizeSurvival(accrualTime = accrualTime, pi1 = 0.23, pi2 = 0.3, followUpTime = 6)
},error = function(e) {
print(e$message)
} )
[1] "Illegal argument: the calculation of 'maxNumberOfSubjects' for given 'followUpTime' and relative accrual intensities (< 1) can only be done if end of accrual is defined"
How to show accrual time details
You can use a sample size or power object as argument for function getAccrualTime
:
<- getSampleSizeSurvival(
sampleSize accrualTime = c(0, 6), accrualIntensity = c(22, 53),
lambda2 = 0.05, hazardRatio = 0.8, followUpTime = 6
)kable(sampleSize)
Design plan parameters and output for survival data
Design parameters
- Critical values: 1.96
- Significance level: 0.0250
- Type II error rate: 0.2000
- Test: one-sided
User defined parameters
- lambda(2): 0.050
- Hazard ratio: 0.800
- Accrual intensity: 22.0, 53.0
- Follow up time: 6.00
Default parameters
- Theta H0: 1
- Type of computation: Schoenfeld
- Planned allocation ratio: 1
- kappa: 1
- Piecewise survival times: 0.00
- Drop-out rate (1): 0.000
- Drop-out rate (2): 0.000
- Drop-out time: 12.00
Sample size and output
- Direction upper: FALSE
- median(1): 17.3
- median(2): 13.9
- lambda(1): 0.040
- Maximum number of subjects: 1205.9
- Number of events: 630.5
- Accrual time: 6.00, 26.26
- Total accrual time: 26.26
- Number of events fixed: 630.5
- Number of subjects fixed: 1205.9
- Number of subjects fixed (1): 602.9
- Number of subjects fixed (2): 602.9
- Analysis times: 32.26
- Study duration: 32.26
- Critical values (treatment effect scale): 0.855
Legend
- (i): values of treatment arm i
<- getAccrualTime(sampleSize)
accrualTime kable(accrualTime)
Accrual time and intensity
- 0 - <=6: 22
- 6 - <=[?]: 53
Formula
- maxNumberOfSubjects = 6 * 22 + (x - 6) * 53, where ‘x’ is the unknown last accrual time
Case (#7)
- ‘followUpTime’ and absolute accrual intensity are given, end of accrual** and ‘maxNumberOfSubjects’** shall be calculated
- Example: getAccrualTime(accrualTime = c(0, 6), accrualIntensity = c(22, 33))
- (*) Can be calculated directly.
- (**) Cannot be calculated directly but with ‘getSampleSizeSurvival()’ or ‘getPowerSurvival()’.
Details
User defined parameters
- Accrual time: 0.00, 6.00
- Accrual intensity: 22.0, 53.0
Generated parameters
- End of accrual is user defined: FALSE
- Follow-up time must be user defined: TRUE
- Max number of subjects is user defined: FALSE
- Max number of subjects can be calculated directly: FALSE
- Absolute accrual intensity is enabled: TRUE
System: rpact 3.3.4, R version 4.2.2 (2022-10-31 ucrt), platform: x86_64-w64-mingw32
To cite R in publications use:
R Core Team (2022). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL https://www.R-project.org/.
To cite package ‘rpact’ in publications use:
Wassmer G, Pahlke F (2023). rpact: Confirmatory Adaptive Clinical Trial Design and Analysis. https://www.rpact.org, https://www.rpact.com, https://github.com/rpact-com/rpact.