Mind the gap: evidence that child mental health inequalities are increasing in the UK

Excerpt

The aim of this editorial is to highlight an important paper published by Collishaw and colleagues in the current edition of the journal [1]. It examines changes in child mental health inequalities in the UK over a period of 13 years by analysing data from three population-based cohorts, the British Child and Adolescent Mental Health Surveys (1999 and 2004) and the Millennium Cohort Study (2012). In each case, parent- and teacher-report data on mental health problems were collected using the same measure—the Strengths and Difficulties Questionnaire (SDQ). The authors focused on the total problems scale which is a composite of the hyperactivity, conduct, emotional, and peer problems scales, and compared the children in the lowest income quintile with those above this income threshold (the wealthiest 80%). The picture that emerges from these analyses is stark and concerning—that whether assessed by parent-report or teacher-report, the mental health gap between the poorest children in society and the rest of the population is increasing. The effect size for the difference in overall mental health problems between the children from the lowest income families compared with those from the wealthiest families increased from 0.35 in 1999 to 0.54 in 2012 (as assessed by parent-report), and from 0.41 in 1999 to 0.57 in 2012 (as assessed by teacher-report). This gave rise to a cohort-by-income interaction for parent-reported mental health problems (p = 0.01), with a clear trend towards a similar interaction for teacher-reported problems (p = 0.09). This study had a number of methodological strengths, including the population-based nature of the samples used in the analyses, the similarity between the samples in terms of age (all were 11 years of age), the use of consistent measures to assess mental health over the sampling period (the SDQ), and the collection of data on the children’s mental health from multiple informants. The findings are also unlikely to be driven by increasing awareness of mental health problems in the poorest children over this period, because the data were not based on referrals or related to help-seeking, and overall levels of mental health problems did not change significantly across the measurement period—instead, the increase in problems was restricted to the poorest children in the sample. …