Table 3

Variables of equation 2, estimating the probability for a male or female infant of needing treatment for IHPS

β, male SE p value β, female SE p value
β0, constant+1.972891.35467+3.367702.91945
Y, days after 31 Dec 1986+0.000640.000740.3851−0.001250.001470.3944
Z, latitude, degrees−0.128330.02315<0.0001−0.177930.049990.0004
Y·Z, (days) · (latitude)−0.000010.000010.2878+0.000020.000030.4210
  • The interaction term, Y·Z, was used in order to specifically investigate whether variation in incidence with time (Y) is related to latitude (Z).