IQ and non-clinical psychotic symptoms in 12-year-olds: results from the ALSPAC birth cohort.

Br J Psychiatry 2008 Sep;193(3):185-91

Department of Social Medicine, University of Bristol, UK.

Background: Non-clinical psychotic symptoms appear common in children, but it is possible that a proportion of reported symptoms result from misinterpretation. There is a well-established association between pre-morbid low IQ score and schizophrenia. Psychosis-like symptoms in children may also be a risk factor for psychotic disorder but their relationship with IQ is unclear.

Aims: To investigate the prevalence, nature and frequency of psychosis-like symptoms in 12-year-old children and study their relationship with IQ.

Method: Longitudinal study using the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort. A total of 6455 children completed screening questions for 12 psychotic symptoms followed by a semi-structured clinical assessment. IQ was assessed at 8 years of age using the Wechsler Intelligence Scale for Children (3rd UK edition).

Results: The 6-month period prevalence for one or more symptoms was 13.7% (95% CI 12.8-14.5). After adjustment for confounding variables, there was a non-linear association between IQ score and psychosis-like symptoms, such that only those with below average IQ score had an increased risk of reporting such symptoms.

Conclusions: Non-clinical psychotic symptoms occur in a significant proportion of 12-year-olds. Symptoms are associated with low IQ and also less strongly with a high IQ score. The pattern of association with IQ differs from that observed in schizophrenia.

Download full-text PDF

Source
http://dx.doi.org/10.1192/bjp.bp.108.051904DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2806573PMC
September 2008
24 Reads

Publication Analysis

Top Keywords

psychotic symptoms
16
psychosis-like symptoms
12
non-clinical psychotic
12
symptoms
10
birth cohort
8
alspac birth
8
longitudinal study
8
children
6
assessed years
4
years age
4
clinical assessment
4
semi-structured clinical
4
age wechsler
4
assessment assessed
4
scale children
4
editionresults 6-month
4
6-month period
4
3rd editionresults
4
children 3rd
4
intelligence scale
4

Similar Publications