Model assumptions |
∙Stratified approach, i.e. |
∙Stratified approach, i.e |
Not applicable because no |
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all 1st events in 1st stratum, |
all 1st events in 1st stratum, |
underlying model is specified. |
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all 2nd events in 2nd stratum, |
all 2nd events in second stratum, |
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and so on. I.e. individuals are at |
and so on. I.e. individuals are at |
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risk for a subsequent event |
riskrisk for a subsequent event |
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only if a previous event has occurred. |
only if a previous event has occurred. |
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Strong assumption |
∙ Proportional hazards are |
∙ Proportional hazards are |
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assumed within strata |
assumed within strata |
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and event types. |
and event types. |
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→ Equal cause-specific |
→ Equal cause-specific baseline |
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baseline hazards. |
hazards (or specific underlying |
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event distribution) |
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→ Baseline hazards can be |
→ Baseline hazards can be |
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strata-specific, i.e. risk for |
strata-specific, i.e. risk for |
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subsequent events |
subsequent events |
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is allowed to change. |
is allowed to change. |
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Estimation assumptions |
No difference to |
Cause-specific hazards |
∙ No difference between strata, i.e. |
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model assumptions. |
are different. |
no risk change for subsequent event. |
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∙ Individuals are at risk as long as |
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they are under observation |
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but their contribution to the |
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event number and number at risk |
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changes for subsequent events. |
Weights |
∙ pre-specified |
∙ pre-specified |
∙ pre-specified |
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∙ non-negative |
∙ non-negative |
∙ non-negative |
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∙ relative weights |
∙ weights based on |
∙ relative weights |
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clinical relevance |
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∙ sum up to 1 |
∙ proposed highest weight of 1 |
∙ highest weight of 1 (for 1 type) |
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but could be higher |
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∙ works multiplicatly on the |
∙ works multiplicatly on the |
∙ works accumulatively multiplicative |
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logarithmized cause-specific |
cause-specific hazards (event counts) |
on the event count |
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hazard ratios |
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Test statistic |
multivariate procedure |
stratified weight based |
modified log-rank test |
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(semi-parametric) |
log-rank test |
(not stratified) |
Effect estimator |
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x |
Confidence interval for effect |
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only bootstrap |
x |
Interpretation |
∙ Weighted cause-specific |
∙ Weighted cause-specific |
Weighted individual score |
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logarithmic hazard ratios. |
hazards work on |
for event count and risk set. |
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Thus influence of event counts is not |
the event counts and hence is |
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directely incoporated, i.e. a higher |
also satisfying in terms of variablity |
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cause-specific logarithmic hazard ratio |
for a low event number. |
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has a higher influence on |
Thus the composite effect is |
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the composite effect, which |
determined by the distribution of |
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results in a higher |
the clinically more relevant event. |
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variability when the estimation |
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is based on a low event number. |
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∙ weighted composite hazard ratio based |
∙ weighted composite effect based on |
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on weighted cause-specific |
weighted cause-specific hazards |
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logarthimic hazard ratios |
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