Population mean scores predict child mental disorder rates: validating SDQ prevalence estimators in Britain

Abstract

Goodman, A; Goodman, R (2010) Population mean scores predict child mental disorder rates: validating SDQ prevalence estimators in Britain. Journal of child psychology and psychiatry, and allied disciplines. ISSN 0021-9630 DOI: 10.1111/j.1469-7610.2010 AbstractBackground: For adult physical and mental health, the population mean predicts the proportion of individuals with "high" scores. This has not previously been investigated for child mental health. It is also unclear how far symptom scores on brief questionnaires provide an unbiased method of comparing children with different individual, family or social characteristics.Methods: Subjects were 18 415 British children aged 5-16 years. Parents, teachers and children aged 11-16 completed Strengths and Difficulties Questionnaires (SDQs) and diagnostic interviews; the latter were used to assign multi-informant clinician-rated diagnoses. We examined how closely the prevalence of child mental disorder was predicted by SDQ mean total difficulty scores, and how these mean scores compared to alternative SDQ-based summary statistics. We did this for populations defined in terms of a wide range of risk factors using one randomly selected half of the study sample. Using these results we generated SDQ prevalence estimator equations, and validated these on the second half of the study sample.Results: Mean symptom scores closely predicted the prevalence of clinician-rated child mental disorder (R 2 =0.89-0.95) and performed better than alternative summary statistics based on binary SDQ outcomes. The predictions of the SDQ prevalence estimators were on average only 1-2% different from the true prevalence, with no systematic tendency towards under-or overestimation. There were only a few outlier subpopulations, all relating to children with learning difficulties. Conclusion:The proportion of children with a disorder is closely predicted by mean symptom scores, highlighting the potential importance of population-wide interventions to improve child mental health. In Britain, SDQ mean total difficulty scores generally provide an accurate and unbiased method of assessing the mental health of different subgroups. SDQ prevalence estimators may facilitate presenting these research findings as proportions that are more easily interpreted by policymakers and service providers.

Bullying of Preterm Children and Emotional Problems at School Age: Cross-Culturally Invariant Effects

“…The SDQ has been shown to be reliable and valid in identifying mental health problems. 16,17 Cronbach's Alpha was 0.72 for VP/VLBW (BLS); 0.75 for EP (EPICure); 0.68 for term comparisons (BLS and EPICure).…”

“…EPICure: Parents reported on peer bullying in one item of the Strengths and Difficulties Questionnaire (SDQ) 16 ("other children pick on or bully him/her") at both ages. The parents' responses were on a 3-point scale.…”

“…At age 13 years (year 6/7) being bullied was assessed using one item of the Strengths and Difficulties Questionnaire (SDQ) 16 completed by the parents: "other children pick on or bully him/her". 9 The parents' responses were on a 3-point scale.…”

Measuring adolescent mental health around the globe: psychometric properties of the self-report Strengths and Difficulties Questionnaire in South Africa, and comparison with UK, Australian and Chinese data

“…However, crosscountry differences in SDQ population means were not supported by the DAWBA individual clinical assessment of study participants. The authors of the SDQ therefore suggested that differences in crosscountry means may not be indicators of differential rates of mental disorders (Goodman & Goodman, 2011), but may rather reflect the lack of populationspecific norms to make 'valid' cross-country comparisons (Goodman et al 2012).…”

Emotional and behavioural difficulties and mental (ill)health

“…That is to say that those who are struggling do not form a discrete group (Figure 1), although the proportion with disorder has a linear association with mean symptoms scores (Goodman and Goodman 2011). The level of impairment for any given constellation of difficulties will be influenced by the social and psychological predicament of the individual, something explored in relation to Attention Deficit Hyperactivity Disorder and school context in this issue (Gwernan-Jones et al).…”