The multiplicative interaction between daily lifting and job strain model (approach I) on the odds ratio (OR) of giving birth to a child born small for gestational age (SGA) or large for gestational age (LGA) compared to appropriate for gestational age (AGA). The Danish National Birth Cohort (N = 47 582).

The results are presented within the stratum of lifting at 250 kg and within the four strata of the job strain model. P-values for the multiplicative interaction between lifting and the job strain model in the three models: Model 1, P = 0.04; Model 2, P = 0.003; Model 3, P = 0.003.