SOCIAL-CLASS DIFFERENCES IN HEALTH UNTIL THE AGE OF 7 YEARS AMONG THEFINNISH 1987 BIRTH COHORT

Studies on social class differences in childhood health are controvers ial partly because of different data collection methods, limited sampl e sizes and the use of limited numbers of health indicators. The incre asing collection of health register data enables the use of such data in social class studies. Our purpose was to investigate social class d ifferences in mortality and morbidity among all children born in Finla nd in 1987 (N = 59,865 liveborns) until the age of seven by using seve ral national health registers, and to study whether perinatal health e xplains these differences.The follow-up was based on data linkage with six national health registers, with 18 regional registers of mentally disabled children, covering the whole country, and with 38 educationa l registers of the largest county. Morbidity was measured in terms of a cumulative disease index, the cumulative incidence of asthma, diabet es, epilepsy and intellectual disability, hospitalisations, disease-re lated welfare benefits and special education. Social class, divided in four groups (I-III, Others) was defined by using the mother's occupat ion at the time the child was seven years old. Our study showed that r egister-based data collection is a feasible method for studying social class differences in health. In the unadjusted analysis, social class differences were found for all indicators except mortality after the age of one year and for the cumulative incidence of asthma and diabete s. After adjusting for confounders, the children in the lowest social class had the highest risk for poor health outcome both in the perinat al period and in childhood, and had the most intellectual disabilities , the highest mean of hospitalisation days, and received the most spec ial education. The differences were not explained by perinatal health. The health of the children in the lowest social class was poorer, espe cially regarding mental indicators. (C) 1998 Elsevier Science Ltd. All rights reserved.