Estimating the impact of child and early adolescent depression on subsequent educational attainment: secondary analysis of an existing data linkage.

AIMS: Depression is thought to be associated with lower subsequent educational attainment during school. But, without longitudinal studies which take account of prior attainment and other potential confounders, estimates of the impact of clinically recognised depression in childhood and early adolescence are unknown. We investigated whether a clinical diagnosis of depression is associated with lower subsequent educational attainment, and whether the association is modified by gender, ethnicity and socioeconomic status. METHODS: We conducted a secondary analysis of an existing administrative data linkage between national educational data and a large mental healthcare provider in London, UK (2007-2013). Depression diagnosis before age 15 (exposure) was measured from electronic health records, and subsequent educational attainment at age 15-16 (outcome) was measured from educational records. We fitted logistic regression models and adjusted for gender, ethnicity, socioeconomic status, relative age in school year, neurodevelopmental disorder diagnosis and prior attainment. We investigated effect modifiers using interaction terms. RESULTS: In total, n = 63 623 were included in analysis, of whom n = 242 had record of a depression diagnosis before age 15. Depression was associated with lower odds of subsequently achieving expected attainment levels in national exams, after adjustment for all covariates (odds ratio = 0.60, 95% confidence interval = 0.43 to 0.84, p = 0.003). There was no evidence that gender, ethnicity or socioeconomic status modified this association. CONCLUSIONS: These findings support a relationship between depression and lower subsequent educational attainment. This highlights the need for tailored educational interventions to support children and adolescents with depression, particularly in the lead up to key educational milestones.

3D flame topography obtained by tomographic chemiluminescence with direct comparison to planar Mie scattering measurements.

This work reports the measurements of 3D flame topography using tomographic chemiluminescence and its validation by direct comparison against planar Mie scattering measurements. Tomographic measurements of the 3D topography of various well-controlled laboratory flames were performed using projections measured by seven cameras, and a simultaneous Mie scattering measurement was performed to measure a 2D cross section of the 3D flame topography. The tomographic measurements were based on chemiluminescence emissions from the flame, and the Mie scattering measurements were based on micrometer-size oil droplets seeded into the flow. The flame topography derived from the 3D tomographic and the Mie scattering measurement was then directly compared. The results show that the flame topography obtained from tomographic chemiluminescence and the Mie measurement agreed qualitatively (i.e., both methods yielded the same profile of the flame fronts), but a quantitative difference on the order of millimeters was observed between these two methods. These results are expected to be useful for understanding the capabilities and limitations of the 3D tomographic and Mie scattering techniques in combustion diagnostics.