The impact of wearing glasses on early literacy

In the previous issue of Best Evidence in Brief, we reported on a study  that showed how wearing glasses improved children’s reading. A similar study by Alison Bruce and colleagues (including the IEE’s Bette Chambers) looks at the impact of wearing glasses on children’s eyesight and early literacy in the UK.

Born in Bradford is a longitudinal study looking at the progress of a multi-ethnic birth cohort in the city of Bradford. From this cohort, 2,930 children underwent a vision screening test in their Reception year. The 432 children who failed the test were referred for follow-up (usually being prescribed glasses) and comprised the treatment group. A further 512 children who passed the sight test were chosen at random to make up the control group. All the children completed tests of literacy (Woodcock Reading Mastery Tests-Revised) and vocabulary (British Vocabulary Picture Scale) at school entry (Year 1) and after 12 months and 24 months. At the same time, researchers checked that the children were wearing their glasses.

The visual acuity of all children improved during the study, but those children who wore their glasses improved most and almost closed the gap on the control children. Letter identification scores declined by 1.5% for every one line reduction (on the LogMar sight chart) in visual acuity. The effect size of wearing glasses was +0.11. The results suggest that failure to wear glasses has implications for young children’s vision and education. Wearing glasses improves both visual acuity and has the potential to improve literacy.

Source: The effect of adherence to spectacle wear on early developing literacy: a longitudinal study based in a large multiethnic city, Bradford, UK (June 2018), BMJ Open

Can schools help prevent childhood obesity?

A study published in The BMJ tests the effectiveness of a school and family based healthy lifestyle intervention (WAVES) in preventing childhood obesity.

Almost 1,500 pupils, aged five- and six-years-old, from 54 primary schools in the West Midlands took part in a randomised controlled trial of the WAVES programme. The twelve-month intervention encouraged healthy eating and physical activity, and included an additional 30 minutes of daily physical activity at school and a six-week programme with a local premiership football club.

Children’s measurements – including weight, height, percentage body fat, waist circumference, skinfold thickness and blood pressure – were taken when they started the trial. These measurements were taken again 15 months and 30 months later and were compared with children in a control group.

At the first follow-up at 15 months, the mean body mass index (BMI) score was not significantly lower for the intervention group compared with the control group. At 30 months, the mean difference was smaller and remained non-significant. The results suggest that schools alone may not be effective in preventing childhood obesity.

Source: Effectiveness of a childhood obesity prevention programme delivered through schools, targeting 6 and 7 year olds: cluster randomised controlled trial (WAVES study) (February 2018), BMJ 2018; 360:k211