Table 4.

Interaction of P-values^a when assessing effect modification between SES measures and census (period of diagnosis) and SES measures and age at diagnosis, for leukemia (and ALL) respectively.

	Census		Age at diagnosis
	Leukemia	ALL	Leukemia	ALL
SES	P	P	P	P
Education status of the mother	0.229	0.139	0.761	0.782
Education status of the father	0.101	0.287	0.458	0.478
Rooms per person	0.650	0.606	0.828	0.760
Living space (in m2)	0.402	0.537	0.173	0.422
Area-based SES index	0.111	0.065	0.207	0.675

ALL indicates acute lymphoblastic leukemia; P, P-values for interaction.

^aModels were adjusted for maternal age, paternal age, nationality, language region, number of older children in household in addition to effect modification parameters.