Table 2.

Comparison between possible partial age-period-cohort models to fit incidence data of ALL at ages 1 to 5 yr (CCRP 1980-1997)

ModelVariablesComparisonP*
1Constant only
2Child birth cohort2 vs 10.084
3Child birth cohort, drift3 vs 20.012
4Drift3 vs 40.169
5Child birth cohort, maternal age5 vs 30.122
6Child birth cohort, maternal birth cohort6 vs 30.639
  • * P value obtained from a likelihood ratio test.

  • Drift denotes the linear component of the temporal variation of rates due to the effect of maternal age or maternal birth cohort, with no possibility of distinguishing between the two.