fitting smooth in time prognostic risk functions via

Fitting smooth-in-time prognostic risk functions via logistic - PowerPoint PPT Presentation

Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary Fitting smooth-in-time prognostic risk functions via logistic regression James A. Hanley 1 Olli S. Miettinen 1 1 Department of


  1. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FORM h ( x , t ) = e g ( x , t ,Ξ² ) log { h ( x , t ) } = g ( x , t , Ξ² ) ⇐ β‡’ β€’ x is a realization of the covariate vector X , representing the patient profile P , and possible intervention I . β€’ Ξ² : a vector of parameters with unknown values, β€’ g () includes constant 1, variates for P , I and t ; β€’ g () can have product terms involving P , I , and t . β€’ g () must be β€˜linear’ in parameters, in β€˜ linear model’ sense. ————– β€’ β€˜proportional hazards’ if no product terms involving t & I β€’ If t is represented by a linear term (so that β€˜time to event’ ∼ Gompertz ), then οΏ½ CI p , i ( t ) has a closed smooth form. β€’ If t is replaced by log t , then β€˜time to event’ ∼ Weibull .

  2. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FORM h ( x , t ) = e g ( x , t ,Ξ² ) log { h ( x , t ) } = g ( x , t , Ξ² ) ⇐ β‡’ β€’ x is a realization of the covariate vector X , representing the patient profile P , and possible intervention I . β€’ Ξ² : a vector of parameters with unknown values, β€’ g () includes constant 1, variates for P , I and t ; β€’ g () can have product terms involving P , I , and t . β€’ g () must be β€˜linear’ in parameters, in β€˜ linear model’ sense. ————– β€’ β€˜proportional hazards’ if no product terms involving t & I β€’ If t is represented by a linear term (so that β€˜time to event’ ∼ Gompertz ), then οΏ½ CI p , i ( t ) has a closed smooth form. β€’ If t is replaced by log t , then β€˜time to event’ ∼ Weibull .

  3. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FORM h ( x , t ) = e g ( x , t ,Ξ² ) log { h ( x , t ) } = g ( x , t , Ξ² ) ⇐ β‡’ β€’ x is a realization of the covariate vector X , representing the patient profile P , and possible intervention I . β€’ Ξ² : a vector of parameters with unknown values, β€’ g () includes constant 1, variates for P , I and t ; β€’ g () can have product terms involving P , I , and t . β€’ g () must be β€˜linear’ in parameters, in β€˜ linear model’ sense. ————– β€’ β€˜proportional hazards’ if no product terms involving t & I β€’ If t is represented by a linear term (so that β€˜time to event’ ∼ Gompertz ), then οΏ½ CI p , i ( t ) has a closed smooth form. β€’ If t is replaced by log t , then β€˜time to event’ ∼ Weibull .

  4. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FORM h ( x , t ) = e g ( x , t ,Ξ² ) log { h ( x , t ) } = g ( x , t , Ξ² ) ⇐ β‡’ β€’ x is a realization of the covariate vector X , representing the patient profile P , and possible intervention I . β€’ Ξ² : a vector of parameters with unknown values, β€’ g () includes constant 1, variates for P , I and t ; β€’ g () can have product terms involving P , I , and t . β€’ g () must be β€˜linear’ in parameters, in β€˜ linear model’ sense. ————– β€’ β€˜proportional hazards’ if no product terms involving t & I β€’ If t is represented by a linear term (so that β€˜time to event’ ∼ Gompertz ), then οΏ½ CI p , i ( t ) has a closed smooth form. β€’ If t is replaced by log t , then β€˜time to event’ ∼ Weibull .

  5. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FORM h ( x , t ) = e g ( x , t ,Ξ² ) log { h ( x , t ) } = g ( x , t , Ξ² ) ⇐ β‡’ β€’ x is a realization of the covariate vector X , representing the patient profile P , and possible intervention I . β€’ Ξ² : a vector of parameters with unknown values, β€’ g () includes constant 1, variates for P , I and t ; β€’ g () can have product terms involving P , I , and t . β€’ g () must be β€˜linear’ in parameters, in β€˜ linear model’ sense. ————– β€’ β€˜proportional hazards’ if no product terms involving t & I β€’ If t is represented by a linear term (so that β€˜time to event’ ∼ Gompertz ), then οΏ½ CI p , i ( t ) has a closed smooth form. β€’ If t is replaced by log t , then β€˜time to event’ ∼ Weibull .

  6. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FORM h ( x , t ) = e g ( x , t ,Ξ² ) log { h ( x , t ) } = g ( x , t , Ξ² ) ⇐ β‡’ β€’ x is a realization of the covariate vector X , representing the patient profile P , and possible intervention I . β€’ Ξ² : a vector of parameters with unknown values, β€’ g () includes constant 1, variates for P , I and t ; β€’ g () can have product terms involving P , I , and t . β€’ g () must be β€˜linear’ in parameters, in β€˜ linear model’ sense. ————– β€’ β€˜proportional hazards’ if no product terms involving t & I β€’ If t is represented by a linear term (so that β€˜time to event’ ∼ Gompertz ), then οΏ½ CI p , i ( t ) has a closed smooth form. β€’ If t is replaced by log t , then β€˜time to event’ ∼ Weibull .

  7. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FORM h ( x , t ) = e g ( x , t ,Ξ² ) log { h ( x , t ) } = g ( x , t , Ξ² ) ⇐ β‡’ β€’ x is a realization of the covariate vector X , representing the patient profile P , and possible intervention I . β€’ Ξ² : a vector of parameters with unknown values, β€’ g () includes constant 1, variates for P , I and t ; β€’ g () can have product terms involving P , I , and t . β€’ g () must be β€˜linear’ in parameters, in β€˜ linear model’ sense. ————– β€’ β€˜proportional hazards’ if no product terms involving t & I β€’ If t is represented by a linear term (so that β€˜time to event’ ∼ Gompertz ), then οΏ½ CI p , i ( t ) has a closed smooth form. β€’ If t is replaced by log t , then β€˜time to event’ ∼ Weibull .

  8. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FORM h ( x , t ) = e g ( x , t ,Ξ² ) log { h ( x , t ) } = g ( x , t , Ξ² ) ⇐ β‡’ β€’ x is a realization of the covariate vector X , representing the patient profile P , and possible intervention I . β€’ Ξ² : a vector of parameters with unknown values, β€’ g () includes constant 1, variates for P , I and t ; β€’ g () can have product terms involving P , I , and t . β€’ g () must be β€˜linear’ in parameters, in β€˜ linear model’ sense. ————– β€’ β€˜proportional hazards’ if no product terms involving t & I β€’ If t is represented by a linear term (so that β€˜time to event’ ∼ Gompertz ), then οΏ½ CI p , i ( t ) has a closed smooth form. β€’ If t is replaced by log t , then β€˜time to event’ ∼ Weibull .

  9. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FORM h ( x , t ) = e g ( x , t ,Ξ² ) log { h ( x , t ) } = g ( x , t , Ξ² ) ⇐ β‡’ β€’ x is a realization of the covariate vector X , representing the patient profile P , and possible intervention I . β€’ Ξ² : a vector of parameters with unknown values, β€’ g () includes constant 1, variates for P , I and t ; β€’ g () can have product terms involving P , I , and t . β€’ g () must be β€˜linear’ in parameters, in β€˜ linear model’ sense. ————– β€’ β€˜proportional hazards’ if no product terms involving t & I β€’ If t is represented by a linear term (so that β€˜time to event’ ∼ Gompertz ), then οΏ½ CI p , i ( t ) has a closed smooth form. β€’ If t is replaced by log t , then β€˜time to event’ ∼ Weibull .

  10. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FITTING β€’ Unable to find a ready-to-use ML procedure within the common statistical packages. β€’ Likelihood becomes quite involved even if no censored observations. β€’ Albertsen & Hanley(’98); Efron(’88, ’02); Carstensen(’00): - divide β€˜survival time’ of each subject into time-slices; - treat # of events in each ∼ Binomial / Poisson.

  11. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FITTING β€’ Unable to find a ready-to-use ML procedure within the common statistical packages. β€’ Likelihood becomes quite involved even if no censored observations. β€’ Albertsen & Hanley(’98); Efron(’88, ’02); Carstensen(’00): - divide β€˜survival time’ of each subject into time-slices; - treat # of events in each ∼ Binomial / Poisson.

  12. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FITTING β€’ Unable to find a ready-to-use ML procedure within the common statistical packages. β€’ Likelihood becomes quite involved even if no censored observations. β€’ Albertsen & Hanley(’98); Efron(’88, ’02); Carstensen(’00): - divide β€˜survival time’ of each subject into time-slices; - treat # of events in each ∼ Binomial / Poisson.

  13. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FULLY-PARAMETRIC MODEL: FITTING β€’ Unable to find a ready-to-use ML procedure within the common statistical packages. β€’ Likelihood becomes quite involved even if no censored observations. β€’ Albertsen & Hanley(’98); Efron(’88, ’02); Carstensen(’00): - divide β€˜survival time’ of each subject into time-slices; - treat # of events in each ∼ Binomial / Poisson.

  14. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTING: OUR APPROACH β€’ An extension of the method of Mantel (1973) to binary outcomes that deals with time dimension. β€’ Mantel’s problem: β€’ ( c =) 165 β€˜cases’ of Y = 1 , β€’ 4000 instances of Y = 0 . β€’ Associated regressor vector X for each of the 4165 β€’ A logistic model for Prob ( Y = 1 | X ) β€’ A computer with limited capacity.

  15. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTING: OUR APPROACH β€’ An extension of the method of Mantel (1973) to binary outcomes that deals with time dimension. β€’ Mantel’s problem: β€’ ( c =) 165 β€˜cases’ of Y = 1 , β€’ 4000 instances of Y = 0 . β€’ Associated regressor vector X for each of the 4165 β€’ A logistic model for Prob ( Y = 1 | X ) β€’ A computer with limited capacity.

  16. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTING: OUR APPROACH β€’ An extension of the method of Mantel (1973) to binary outcomes that deals with time dimension. β€’ Mantel’s problem: β€’ ( c =) 165 β€˜cases’ of Y = 1 , β€’ 4000 instances of Y = 0 . β€’ Associated regressor vector X for each of the 4165 β€’ A logistic model for Prob ( Y = 1 | X ) β€’ A computer with limited capacity.

  17. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTING: OUR APPROACH β€’ An extension of the method of Mantel (1973) to binary outcomes that deals with time dimension. β€’ Mantel’s problem: β€’ ( c =) 165 β€˜cases’ of Y = 1 , β€’ 4000 instances of Y = 0 . β€’ Associated regressor vector X for each of the 4165 β€’ A logistic model for Prob ( Y = 1 | X ) β€’ A computer with limited capacity.

  18. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTING: OUR APPROACH β€’ An extension of the method of Mantel (1973) to binary outcomes that deals with time dimension. β€’ Mantel’s problem: β€’ ( c =) 165 β€˜cases’ of Y = 1 , β€’ 4000 instances of Y = 0 . β€’ Associated regressor vector X for each of the 4165 β€’ A logistic model for Prob ( Y = 1 | X ) β€’ A computer with limited capacity.

  19. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTING: OUR APPROACH β€’ An extension of the method of Mantel (1973) to binary outcomes that deals with time dimension. β€’ Mantel’s problem: β€’ ( c =) 165 β€˜cases’ of Y = 1 , β€’ 4000 instances of Y = 0 . β€’ Associated regressor vector X for each of the 4165 β€’ A logistic model for Prob ( Y = 1 | X ) β€’ A computer with limited capacity.

  20. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTING: OUR APPROACH β€’ An extension of the method of Mantel (1973) to binary outcomes that deals with time dimension. β€’ Mantel’s problem: β€’ ( c =) 165 β€˜cases’ of Y = 1 , β€’ 4000 instances of Y = 0 . β€’ Associated regressor vector X for each of the 4165 β€’ A logistic model for Prob ( Y = 1 | X ) β€’ A computer with limited capacity.

  21. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTING: OUR APPROACH β€’ An extension of the method of Mantel (1973) to binary outcomes that deals with time dimension. β€’ Mantel’s problem: β€’ ( c =) 165 β€˜cases’ of Y = 1 , β€’ 4000 instances of Y = 0 . β€’ Associated regressor vector X for each of the 4165 β€’ A logistic model for Prob ( Y = 1 | X ) β€’ A computer with limited capacity.

  22. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary MANTEL ’S SOLUTION β€’ Form a reduced dataset containing... β€’ All c instances (cases) of Y = 1 β€’ Random sample of the Y = 0 observations β€’ Fit the same logistic model to this reduced dataset. β€œSuch sampling will tend to leave the dependence of the log odds on the variables unaffected except for an additive constant.” Anderson (Biometrika, 1972) had noted this too. β€’ Outcome(Choice)-based sampling common in Epi, Marketing, etc...

  23. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary MANTEL ’S SOLUTION β€’ Form a reduced dataset containing... β€’ All c instances (cases) of Y = 1 β€’ Random sample of the Y = 0 observations β€’ Fit the same logistic model to this reduced dataset. β€œSuch sampling will tend to leave the dependence of the log odds on the variables unaffected except for an additive constant.” Anderson (Biometrika, 1972) had noted this too. β€’ Outcome(Choice)-based sampling common in Epi, Marketing, etc...

  24. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary MANTEL ’S SOLUTION β€’ Form a reduced dataset containing... β€’ All c instances (cases) of Y = 1 β€’ Random sample of the Y = 0 observations β€’ Fit the same logistic model to this reduced dataset. β€œSuch sampling will tend to leave the dependence of the log odds on the variables unaffected except for an additive constant.” Anderson (Biometrika, 1972) had noted this too. β€’ Outcome(Choice)-based sampling common in Epi, Marketing, etc...

  25. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary MANTEL ’S SOLUTION β€’ Form a reduced dataset containing... β€’ All c instances (cases) of Y = 1 β€’ Random sample of the Y = 0 observations β€’ Fit the same logistic model to this reduced dataset. β€œSuch sampling will tend to leave the dependence of the log odds on the variables unaffected except for an additive constant.” Anderson (Biometrika, 1972) had noted this too. β€’ Outcome(Choice)-based sampling common in Epi, Marketing, etc...

  26. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary MANTEL ’S SOLUTION β€’ Form a reduced dataset containing... β€’ All c instances (cases) of Y = 1 β€’ Random sample of the Y = 0 observations β€’ Fit the same logistic model to this reduced dataset. β€œSuch sampling will tend to leave the dependence of the log odds on the variables unaffected except for an additive constant.” Anderson (Biometrika, 1972) had noted this too. β€’ Outcome(Choice)-based sampling common in Epi, Marketing, etc...

  27. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary MANTEL ’S SOLUTION β€’ Form a reduced dataset containing... β€’ All c instances (cases) of Y = 1 β€’ Random sample of the Y = 0 observations β€’ Fit the same logistic model to this reduced dataset. β€œSuch sampling will tend to leave the dependence of the log odds on the variables unaffected except for an additive constant.” Anderson (Biometrika, 1972) had noted this too. β€’ Outcome(Choice)-based sampling common in Epi, Marketing, etc...

  28. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary MANTEL ’S SOLUTION β€’ Form a reduced dataset containing... β€’ All c instances (cases) of Y = 1 β€’ Random sample of the Y = 0 observations β€’ Fit the same logistic model to this reduced dataset. β€œSuch sampling will tend to leave the dependence of the log odds on the variables unaffected except for an additive constant.” Anderson (Biometrika, 1972) had noted this too. β€’ Outcome(Choice)-based sampling common in Epi, Marketing, etc...

  29. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary DATA TO EXPLAIN OUR APPROACH Systolic Hypertension in Elderly Program (SHEP) .......................... SHEP Cooperative Research Group (1991). .......................... Journal of American Medical Association 265, 3255-3264. β€’ 4,701 persons with complete data on P = { age, sex, race, and systolic blood pressure} and I = { active/placebo}. β€’ Study base of B = 20 , 894 person-years of follow-up; c = 263 events ("cases") of stroke identified.

  30. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary DATA TO EXPLAIN OUR APPROACH Systolic Hypertension in Elderly Program (SHEP) .......................... SHEP Cooperative Research Group (1991). .......................... Journal of American Medical Association 265, 3255-3264. β€’ 4,701 persons with complete data on P = { age, sex, race, and systolic blood pressure} and I = { active/placebo}. β€’ Study base of B = 20 , 894 person-years of follow-up; c = 263 events ("cases") of stroke identified.

  31. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary DATA TO EXPLAIN OUR APPROACH Systolic Hypertension in Elderly Program (SHEP) .......................... SHEP Cooperative Research Group (1991). .......................... Journal of American Medical Association 265, 3255-3264. β€’ 4,701 persons with complete data on P = { age, sex, race, and systolic blood pressure} and I = { active/placebo}. β€’ Study base of B = 20 , 894 person-years of follow-up; c = 263 events ("cases") of stroke identified.

  32. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary DATA TO EXPLAIN OUR APPROACH Systolic Hypertension in Elderly Program (SHEP) .......................... SHEP Cooperative Research Group (1991). .......................... Journal of American Medical Association 265, 3255-3264. β€’ 4,701 persons with complete data on P = { age, sex, race, and systolic blood pressure} and I = { active/placebo}. β€’ Study base of B = 20 , 894 person-years of follow-up; c = 263 events ("cases") of stroke identified.

  33. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary DATA TO EXPLAIN OUR APPROACH Systolic Hypertension in Elderly Program (SHEP) .......................... SHEP Cooperative Research Group (1991). .......................... Journal of American Medical Association 265, 3255-3264. β€’ 4,701 persons with complete data on P = { age, sex, race, and systolic blood pressure} and I = { active/placebo}. β€’ Study base of B = 20 , 894 person-years of follow-up; c = 263 events ("cases") of stroke identified.

  34. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary STUDY BASE, and the 263 cases 6000 βˆ’ 20,894 personβˆ’years [B=20,894 PY] STUDY BASE βˆ’ 10,982,000,000 personβˆ’minutes (approx) 5000 No. of Persons βˆ’ infinite number of personβˆ’moments ↑ Being Followed c = 263 events (Y=1) ● ● ● ● ● ● ● in this infinite number ● ● ● 4000 ● ● ● ● ● ● ● ● ● ● ● ● ● of personβˆ’moments ● ● ● ● ● ● ● ● ● ● ● ● ● Persons ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● infinite number ● ● ● ● ● ● ● ● 3000 ● ● ● ● ● ● ● ● ● ● of personβˆ’moments ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● with Y=0 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 2000 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 1000 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 0 ● ● ● ● ● 0 1 2 3 4 5 6 7 t: Years since Randomization

  35. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary OUR APPROACH β€’ Base series: representative (unstratified) sample of base. β€’ b : size of base series β€’ B : amount of population-time constituting study base. β€’ B ( x , t ) : population-time element in study base Pr ( Y = 1 | x , t ) Pr ( Y = 0 | x , t ) = h ( x , t ) Γ— B ( x , t ) b Γ— [ B ( x , t ) / B ] = h ( x , t ) Γ— ( B / b ) , β€’ log ( B / b ) is an offset [a regression term with known coefficient of 1] . β†’ logistic model, with t having same status as x , and offset, directly yields οΏ½ ID x , t = exp { οΏ½ h ( x , t ) = οΏ½ g ( x , t ) } .

  36. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary How large should b be on relation to c ? b : no. of instances of Y = 0 ; c : no. of instances of Y = 1 β€’ Mantel (1973)... little to be gained by letting the size of one series, b, become arbitrarily large if the size of the other series, c , must remain fixed. β€’ With 2008 computing, we can use a b / c ratio as high as 100, and thereby extract virtually all of the information in the base.

  37. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary How large should b be on relation to c ? b : no. of instances of Y = 0 ; c : no. of instances of Y = 1 β€’ Mantel (1973)... little to be gained by letting the size of one series, b, become arbitrarily large if the size of the other series, c , must remain fixed. β€’ With 2008 computing, we can use a b / c ratio as high as 100, and thereby extract virtually all of the information in the base.

  38. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary How large should b be on relation to c ? b : no. of instances of Y = 0 ; c : no. of instances of Y = 1 β€’ Mantel (1973)... little to be gained by letting the size of one series, b, become arbitrarily large if the size of the other series, c , must remain fixed. β€’ With 2008 computing, we can use a b / c ratio as high as 100, and thereby extract virtually all of the information in the base.

  39. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary How large should b be on relation to c ? b : no. of instances of Y = 0 ; c : no. of instances of Y = 1 β€’ Mantel (1973)... little to be gained by letting the size of one series, b, become arbitrarily large if the size of the other series, c , must remain fixed. β€’ With 2008 computing, we can use a b / c ratio as high as 100, and thereby extract virtually all of the information in the base.

  40. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary OUR HAZARD MODEL FOR SHEP DATA log [ h ] = Ξ£ Ξ² k X k , where X 1 = Age (in yrs) - 60 X 2 = Indicator of male gender X 3 = Indicator of Black race X 4 = Systolic BP (in mmHg) - 140 ...................................................................... X 5 = Indicator of active treatment ...................................................................... X 6 = T ...................................................................... X 7 = X 5 Γ— X 6 . (non-proportional hazards)

  41. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary OUR HAZARD MODEL FOR SHEP DATA log [ h ] = Ξ£ Ξ² k X k , where X 1 = Age (in yrs) - 60 X 2 = Indicator of male gender X 3 = Indicator of Black race X 4 = Systolic BP (in mmHg) - 140 ...................................................................... X 5 = Indicator of active treatment ...................................................................... X 6 = T ...................................................................... X 7 = X 5 Γ— X 6 . (non-proportional hazards)

  42. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary PARAMETER ESTIMATION β€’ Formed person-moments dataset pertaining to: β€’ case series of size c = 263 ( Y = 1) and β€’ (randomly-selected) base series of size b = 26 , 300 ( Y = 0 ) . β€’ Each of 26,563 rows contained realizations of β€’ X 1 , . . . , X 7 β€’ Y β€’ offset = log ( 20 , 894 / 26 , 300 ) . β€’ Logistic model fitted to data in the two series.

  43. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary PARAMETER ESTIMATION β€’ Formed person-moments dataset pertaining to: β€’ case series of size c = 263 ( Y = 1) and β€’ (randomly-selected) base series of size b = 26 , 300 ( Y = 0 ) . β€’ Each of 26,563 rows contained realizations of β€’ X 1 , . . . , X 7 β€’ Y β€’ offset = log ( 20 , 894 / 26 , 300 ) . β€’ Logistic model fitted to data in the two series.

  44. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary PARAMETER ESTIMATION β€’ Formed person-moments dataset pertaining to: β€’ case series of size c = 263 ( Y = 1) and β€’ (randomly-selected) base series of size b = 26 , 300 ( Y = 0 ) . β€’ Each of 26,563 rows contained realizations of β€’ X 1 , . . . , X 7 β€’ Y β€’ offset = log ( 20 , 894 / 26 , 300 ) . β€’ Logistic model fitted to data in the two series.

  45. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary PARAMETER ESTIMATION β€’ Formed person-moments dataset pertaining to: β€’ case series of size c = 263 ( Y = 1) and β€’ (randomly-selected) base series of size b = 26 , 300 ( Y = 0 ) . β€’ Each of 26,563 rows contained realizations of β€’ X 1 , . . . , X 7 β€’ Y β€’ offset = log ( 20 , 894 / 26 , 300 ) . β€’ Logistic model fitted to data in the two series.

  46. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary PARAMETER ESTIMATION β€’ Formed person-moments dataset pertaining to: β€’ case series of size c = 263 ( Y = 1) and β€’ (randomly-selected) base series of size b = 26 , 300 ( Y = 0 ) . β€’ Each of 26,563 rows contained realizations of β€’ X 1 , . . . , X 7 β€’ Y β€’ offset = log ( 20 , 894 / 26 , 300 ) . β€’ Logistic model fitted to data in the two series.

  47. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary PARAMETER ESTIMATION β€’ Formed person-moments dataset pertaining to: β€’ case series of size c = 263 ( Y = 1) and β€’ (randomly-selected) base series of size b = 26 , 300 ( Y = 0 ) . β€’ Each of 26,563 rows contained realizations of β€’ X 1 , . . . , X 7 β€’ Y β€’ offset = log ( 20 , 894 / 26 , 300 ) . β€’ Logistic model fitted to data in the two series.

  48. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary PARAMETER ESTIMATION β€’ Formed person-moments dataset pertaining to: β€’ case series of size c = 263 ( Y = 1) and β€’ (randomly-selected) base series of size b = 26 , 300 ( Y = 0 ) . β€’ Each of 26,563 rows contained realizations of β€’ X 1 , . . . , X 7 β€’ Y β€’ offset = log ( 20 , 894 / 26 , 300 ) . β€’ Logistic model fitted to data in the two series.

  49. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary PARAMETER ESTIMATION β€’ Formed person-moments dataset pertaining to: β€’ case series of size c = 263 ( Y = 1) and β€’ (randomly-selected) base series of size b = 26 , 300 ( Y = 0 ) . β€’ Each of 26,563 rows contained realizations of β€’ X 1 , . . . , X 7 β€’ Y β€’ offset = log ( 20 , 894 / 26 , 300 ) . β€’ Logistic model fitted to data in the two series.

  50. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary DATASET: c = 263 ; b = 10 Γ— 263 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 4000 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 3000 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● Persons ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 2000 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 1000 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 0 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 0 1 2 3 4 5 6 Time

  51. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTED VALUES Proposed Cox logistic regression regression Ξ² age βˆ’ 60 0.041 0.041 0.041 Ξ² I male 0.257 0.258 0.259 Ξ² I black 0.302 0.301 0.303 Ξ² SBP βˆ’ 140 0.017 0.017 0.017 .................... Ξ² I Active treatment -0.200 -0.435 -0.435 .................... Ξ² 0 -5.390 -5.295 Ξ² t -0.014 -0.057 Ξ² t Γ— I Active treatment -0.107 β€’ Fitted logistic function represents log [ h x ( t )] β€’ β†’ cumulative hazard H X ( t ) , and, thus, X -specific risk.

  52. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTED VALUES Proposed Cox logistic regression regression Ξ² age βˆ’ 60 0.041 0.041 0.041 Ξ² I male 0.257 0.258 0.259 Ξ² I black 0.302 0.301 0.303 Ξ² SBP βˆ’ 140 0.017 0.017 0.017 .................... Ξ² I Active treatment -0.200 -0.435 -0.435 .................... Ξ² 0 -5.390 -5.295 Ξ² t -0.014 -0.057 Ξ² t Γ— I Active treatment -0.107 β€’ Fitted logistic function represents log [ h x ( t )] β€’ β†’ cumulative hazard H X ( t ) , and, thus, X -specific risk.

  53. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTED VALUES Proposed Cox logistic regression regression Ξ² age βˆ’ 60 0.041 0.041 0.041 Ξ² I male 0.257 0.258 0.259 Ξ² I black 0.302 0.301 0.303 Ξ² SBP βˆ’ 140 0.017 0.017 0.017 .................... Ξ² I Active treatment -0.200 -0.435 -0.435 .................... Ξ² 0 -5.390 -5.295 Ξ² t -0.014 -0.057 Ξ² t Γ— I Active treatment -0.107 β€’ Fitted logistic function represents log [ h x ( t )] β€’ β†’ cumulative hazard H X ( t ) , and, thus, X -specific risk.

  54. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary FITTED VALUES Proposed Cox logistic regression regression Ξ² age βˆ’ 60 0.041 0.041 0.041 Ξ² I male 0.257 0.258 0.259 Ξ² I black 0.302 0.301 0.303 Ξ² SBP βˆ’ 140 0.017 0.017 0.017 .................... Ξ² I Active treatment -0.200 -0.435 -0.435 .................... Ξ² 0 -5.390 -5.295 Ξ² t -0.014 -0.057 Ξ² t Γ— I Active treatment -0.107 β€’ Fitted logistic function represents log [ h x ( t )] β€’ β†’ cumulative hazard H X ( t ) , and, thus, X -specific risk.

  55. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary ESTIMATED 5-YEAR RISK OF STROKE Risk I h ( t ) H ( 5 ) CI ( 5 ) βˆ† οΏ½ 5 [ 1 βˆ’ e βˆ’ H ( 5 ) ] [ ID(t) ] [ 0 h x ( t ) dt ] e βˆ’ 4 . 86 βˆ’ 0 . 014 t Low 0 0.037 0.036 e βˆ’ 5 . 06 βˆ’ 0 . 124 t 1 0.024 0.024 1.2% High 0 0.16 1 0.10 6% Overall 0 0.076 1 0.049 2.7% Low: 65 year old white female with a SBP of 160 mmHg. High: 80 year old black male with a SBP of 180 mmHg

  56. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary ESTIMATED 5-YEAR RISK OF STROKE Risk I h ( t ) H ( 5 ) CI ( 5 ) βˆ† οΏ½ 5 [ 1 βˆ’ e βˆ’ H ( 5 ) ] [ ID(t) ] [ 0 h x ( t ) dt ] e βˆ’ 4 . 86 βˆ’ 0 . 014 t Low 0 0.037 0.036 e βˆ’ 5 . 06 βˆ’ 0 . 124 t 1 0.024 0.024 1.2% High 0 0.16 1 0.10 6% Overall 0 0.076 1 0.049 2.7% Low: 65 year old white female with a SBP of 160 mmHg. High: 80 year old black male with a SBP of 180 mmHg

  57. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary ESTIMATED 5-YEAR RISK OF STROKE Risk I h ( t ) H ( 5 ) CI ( 5 ) βˆ† οΏ½ 5 [ 1 βˆ’ e βˆ’ H ( 5 ) ] [ ID(t) ] [ 0 h x ( t ) dt ] e βˆ’ 4 . 86 βˆ’ 0 . 014 t Low 0 0.037 0.036 e βˆ’ 5 . 06 βˆ’ 0 . 124 t 1 0.024 0.024 1.2% High 0 0.16 1 0.10 6% Overall 0 0.076 1 0.049 2.7% Low: 65 year old white female with a SBP of 160 mmHg. High: 80 year old black male with a SBP of 180 mmHg

  58. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary ESTIMATED 5-YEAR RISK OF STROKE Risk I h ( t ) H ( 5 ) CI ( 5 ) βˆ† οΏ½ 5 [ 1 βˆ’ e βˆ’ H ( 5 ) ] [ ID(t) ] [ 0 h x ( t ) dt ] e βˆ’ 4 . 86 βˆ’ 0 . 014 t Low 0 0.037 0.036 e βˆ’ 5 . 06 βˆ’ 0 . 124 t 1 0.024 0.024 1.2% High 0 0.16 1 0.10 6% Overall 0 0.076 1 0.049 2.7% Low: 65 year old white female with a SBP of 160 mmHg. High: 80 year old black male with a SBP of 180 mmHg

  59. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary ESTIMATED 5-YEAR RISK OF STROKE Risk I h ( t ) H ( 5 ) CI ( 5 ) βˆ† οΏ½ 5 [ 1 βˆ’ e βˆ’ H ( 5 ) ] [ ID(t) ] [ 0 h x ( t ) dt ] e βˆ’ 4 . 86 βˆ’ 0 . 014 t Low 0 0.037 0.036 e βˆ’ 5 . 06 βˆ’ 0 . 124 t 1 0.024 0.024 1.2% High 0 0.16 1 0.10 6% Overall 0 0.076 1 0.049 2.7% Low: 65 year old white female with a SBP of 160 mmHg. High: 80 year old black male with a SBP of 180 mmHg

  60. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary ESTIMATED 5-YEAR RISK OF STROKE Risk I h ( t ) H ( 5 ) CI ( 5 ) βˆ† οΏ½ 5 [ 1 βˆ’ e βˆ’ H ( 5 ) ] [ ID(t) ] [ 0 h x ( t ) dt ] e βˆ’ 4 . 86 βˆ’ 0 . 014 t Low 0 0.037 0.036 e βˆ’ 5 . 06 βˆ’ 0 . 124 t 1 0.024 0.024 1.2% High 0 0.16 1 0.10 6% Overall 0 0.076 1 0.049 2.7% Low: 65 year old white female with a SBP of 160 mmHg. High: 80 year old black male with a SBP of 180 mmHg

  61. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary (a.0): 80 year old black male, SBP=180 15 semiβˆ’parametric (Cox) (a.1) proposed Cumulative incidence (%) 10 5 (b.0) (b.1): 65 year old white female, SBP=160 0 0 1 2 3 4 5 Prospective time (years)

  62. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 0 1 2 3 4 5 6 7 8 9 10 Points Age 60 65 70 75 80 85 90 95 100 1 Male 0 1 Black 0 SBP 155 165 175 185 195 205 215 0 I 1 t 6 0 I.t 6 5 4 3 2 1 0 Total Points 0 2 4 6 8 10 12 14 16 18 20 22 Linear Predictor βˆ’6 βˆ’5.5 βˆ’5 βˆ’4.5 βˆ’4 βˆ’3.5 βˆ’3 βˆ’2.5 5βˆ’year Risk (%) if not treated 3 4 5 6 7 8 9 12 15 18 5βˆ’year Risk (%) if treated 2 3 4 5 6 7 8 9 12 15 18

  63. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 1. FEATURES β€’ Smooth-in- t h ( t ) β€”and CI’s– not new; fitting procedure is. β€’ Keys: 1. representative sampling of the base; 2. offset. β€’ b / c =100 feasible and adequate.

  64. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 1. FEATURES β€’ Smooth-in- t h ( t ) β€”and CI’s– not new; fitting procedure is. β€’ Keys: 1. representative sampling of the base; 2. offset. β€’ b / c =100 feasible and adequate.

  65. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 1. FEATURES β€’ Smooth-in- t h ( t ) β€”and CI’s– not new; fitting procedure is. β€’ Keys: 1. representative sampling of the base; 2. offset. β€’ b / c =100 feasible and adequate.

  66. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 1. FEATURES β€’ Smooth-in- t h ( t ) β€”and CI’s– not new; fitting procedure is. β€’ Keys: 1. representative sampling of the base; 2. offset. β€’ b / c =100 feasible and adequate.

  67. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 2. MODELLING POSSIBILITIES Log-linear modelling for h x ( t ) via logistic regression ... β€’ Standard methods to assess model fit. β€’ Wide range of functional forms for the t -dimension of h x ( t ) . β€’ Effortless handling of censored data. β€’ Flexibility in modeling non-proportionality over t . β€’ Splines for h ( t ) rather than hr ( t ) .

  68. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 2. MODELLING POSSIBILITIES Log-linear modelling for h x ( t ) via logistic regression ... β€’ Standard methods to assess model fit. β€’ Wide range of functional forms for the t -dimension of h x ( t ) . β€’ Effortless handling of censored data. β€’ Flexibility in modeling non-proportionality over t . β€’ Splines for h ( t ) rather than hr ( t ) .

  69. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 2. MODELLING POSSIBILITIES Log-linear modelling for h x ( t ) via logistic regression ... β€’ Standard methods to assess model fit. β€’ Wide range of functional forms for the t -dimension of h x ( t ) . β€’ Effortless handling of censored data. β€’ Flexibility in modeling non-proportionality over t . β€’ Splines for h ( t ) rather than hr ( t ) .

  70. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 2. MODELLING POSSIBILITIES Log-linear modelling for h x ( t ) via logistic regression ... β€’ Standard methods to assess model fit. β€’ Wide range of functional forms for the t -dimension of h x ( t ) . β€’ Effortless handling of censored data. β€’ Flexibility in modeling non-proportionality over t . β€’ Splines for h ( t ) rather than hr ( t ) .

  71. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 2. MODELLING POSSIBILITIES Log-linear modelling for h x ( t ) via logistic regression ... β€’ Standard methods to assess model fit. β€’ Wide range of functional forms for the t -dimension of h x ( t ) . β€’ Effortless handling of censored data. β€’ Flexibility in modeling non-proportionality over t . β€’ Splines for h ( t ) rather than hr ( t ) .

  72. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 2. MODELLING POSSIBILITIES Log-linear modelling for h x ( t ) via logistic regression ... β€’ Standard methods to assess model fit. β€’ Wide range of functional forms for the t -dimension of h x ( t ) . β€’ Effortless handling of censored data. β€’ Flexibility in modeling non-proportionality over t . β€’ Splines for h ( t ) rather than hr ( t ) .

  73. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 2. MODELLING POSSIBILITIES Log-linear modelling for h x ( t ) via logistic regression ... β€’ Standard methods to assess model fit. β€’ Wide range of functional forms for the t -dimension of h x ( t ) . β€’ Effortless handling of censored data. β€’ Flexibility in modeling non-proportionality over t . β€’ Splines for h ( t ) rather than hr ( t ) .

  74. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 3. CLINICAL POSSIBILITIES / DESIDERATA β€’ PDAs (personal digital assistants) β†’ online information. β€’ Profile-specific risk estimates for various interventions. β€’ Already, online calculators: risk of MI, Breast/Lung Cancer; probability of extra-organ spread of cancer. β€’ RCT reports should contain: suitably designed risk function, fitted parameters of h x ( t ) , and risk function. β€’ (Offline:) risk scores β†’ risks via nomogram/table.

  75. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 3. CLINICAL POSSIBILITIES / DESIDERATA β€’ PDAs (personal digital assistants) β†’ online information. β€’ Profile-specific risk estimates for various interventions. β€’ Already, online calculators: risk of MI, Breast/Lung Cancer; probability of extra-organ spread of cancer. β€’ RCT reports should contain: suitably designed risk function, fitted parameters of h x ( t ) , and risk function. β€’ (Offline:) risk scores β†’ risks via nomogram/table.

  76. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 3. CLINICAL POSSIBILITIES / DESIDERATA β€’ PDAs (personal digital assistants) β†’ online information. β€’ Profile-specific risk estimates for various interventions. β€’ Already, online calculators: risk of MI, Breast/Lung Cancer; probability of extra-organ spread of cancer. β€’ RCT reports should contain: suitably designed risk function, fitted parameters of h x ( t ) , and risk function. β€’ (Offline:) risk scores β†’ risks via nomogram/table.

  77. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 3. CLINICAL POSSIBILITIES / DESIDERATA β€’ PDAs (personal digital assistants) β†’ online information. β€’ Profile-specific risk estimates for various interventions. β€’ Already, online calculators: risk of MI, Breast/Lung Cancer; probability of extra-organ spread of cancer. β€’ RCT reports should contain: suitably designed risk function, fitted parameters of h x ( t ) , and risk function. β€’ (Offline:) risk scores β†’ risks via nomogram/table.

  78. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 3. CLINICAL POSSIBILITIES / DESIDERATA β€’ PDAs (personal digital assistants) β†’ online information. β€’ Profile-specific risk estimates for various interventions. β€’ Already, online calculators: risk of MI, Breast/Lung Cancer; probability of extra-organ spread of cancer. β€’ RCT reports should contain: suitably designed risk function, fitted parameters of h x ( t ) , and risk function. β€’ (Offline:) risk scores β†’ risks via nomogram/table.

  79. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 3. CLINICAL POSSIBILITIES / DESIDERATA β€’ PDAs (personal digital assistants) β†’ online information. β€’ Profile-specific risk estimates for various interventions. β€’ Already, online calculators: risk of MI, Breast/Lung Cancer; probability of extra-organ spread of cancer. β€’ RCT reports should contain: suitably designed risk function, fitted parameters of h x ( t ) , and risk function. β€’ (Offline:) risk scores β†’ risks via nomogram/table.

  80. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 4. SUMMARY β€’ Profile-specific risk (CI) functions are important. β€’ Two paths to CI, via... β€’ Steps-in-time S 0 ( t ) β€’ Smooth-in-time ID x ( t ) . β€’ New simple estimation method for broad class of smooth-in-time ID / hazard functions. β€’ Biostatistics & Epidemiology methods: a little more unified?

  81. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 4. SUMMARY β€’ Profile-specific risk (CI) functions are important. β€’ Two paths to CI, via... β€’ Steps-in-time S 0 ( t ) β€’ Smooth-in-time ID x ( t ) . β€’ New simple estimation method for broad class of smooth-in-time ID / hazard functions. β€’ Biostatistics & Epidemiology methods: a little more unified?

  82. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 4. SUMMARY β€’ Profile-specific risk (CI) functions are important. β€’ Two paths to CI, via... β€’ Steps-in-time S 0 ( t ) β€’ Smooth-in-time ID x ( t ) . β€’ New simple estimation method for broad class of smooth-in-time ID / hazard functions. β€’ Biostatistics & Epidemiology methods: a little more unified?

  83. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 4. SUMMARY β€’ Profile-specific risk (CI) functions are important. β€’ Two paths to CI, via... β€’ Steps-in-time S 0 ( t ) β€’ Smooth-in-time ID x ( t ) . β€’ New simple estimation method for broad class of smooth-in-time ID / hazard functions. β€’ Biostatistics & Epidemiology methods: a little more unified?

  84. Introduction Smooth-in-time hazard functions How we fit fully-parametric hazard model Illustration Comments/Summary 4. SUMMARY β€’ Profile-specific risk (CI) functions are important. β€’ Two paths to CI, via... β€’ Steps-in-time S 0 ( t ) β€’ Smooth-in-time ID x ( t ) . β€’ New simple estimation method for broad class of smooth-in-time ID / hazard functions. β€’ Biostatistics & Epidemiology methods: a little more unified?

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