Background Low birthweight has been shown to predict behavioural problems i
n children. Less is known about the effect of birthweight, and how this may
interact with the social environment in determining behaviour in a general
population sample. We have examined the relationship between birthweight a
nd social factors on childhood psychological well-being.
Methods Cross-sectional analysis of data on 5181 children aged 4-15 years f
rom a randomly selected household population, the 1997 Health Survey for En
gland. The main outcome measures were behavioural problems as defined by th
e Strengths and Difficulties Questionnaire (SDQ) in relation to birthweight
and social environmental factors.
Results Birthweight was a significant predictor of total difficulties score
(odds ratio [OR] = 1.27, 95% CI: 1.07, 1.49), hyperactivity in boys (OR =
1.25, 95% CI: 1.05, 1.51), and peer problems in girls (OR = 1.24, 95% CI: 0
.99, 1.53). There was a strong social class gradient in the prevalence of b
ehavioural problems for all birthweight tertiles. Bivariate analysis showed
that high total difficulties score was significantly more common in lower
birthweight tertiles for social classes III non-manual and III manual (P-va
lue for trend 0.05 and 0.03, respectively). There were smaller, non-signifi
cant effects of birthweight on the prevalence of behavioural problems in so
cial class I and II, and IV and V. Statistical tests for an interaction bet
ween birthweight and social class were not significant.
Conclusions Early Life factors, such as birthweight and social class have i
mportant influences on psychological well-being in children. The birthweigh
t effect is influenced by social factors, with the possibility that an adva
ntaged social environment protects against the development of behavioural p
roblems, and a disadvantaged environment increases the risk of behavioural
problems, regardless of birthweight.