Impact of congenital colour vision deficiency on education and unintentional injuries: findings from the 1958 British birth cohort

Abstract

Congenital colour vision defects (CVD) are common, inherited (most commonly X linked), non-progressive, and untreatable disorders.1 2 Screening children for these disorders is established practice in the United Kingdom, primarily so that those affected can be advised about occupational preclusions.2 Population based work on the broader impact of colour vision defects is, however, limited. Participants, methods, and resultsWe investigated the association between CVD and education and unintentional injury in the 1958 British birth cohort.3 4 Despite attrition, people remaining were representative of the original sample, including with respect to colour vision status. The latter was assessed in 12 534 children aged 11 years using the Ishihara test, 1 with CVD being the inability to identify all 24 plates. Corrected distance acuity was measured with Snellen charts. We analysed educational, perceptual, and motor skills tests done at 7, 11, and 16 years 3 4 together with highest educational qualification by 33 (none, below O level or equivalent, O level or equivalent, A level or equivalent, or higher). We converted education test scores to z scores 3 and assessed the effect of CVD with multivariate linear regression. We analysed unintentional injuries requiring hospital care by CVD status and sex.Overall, 431 of 6422 boys (6.7%; 95% confidence interval 6.1% to 7.3%) and 68 of 6112 girls (1.1%; 0.8% to 1.4%) had CVD. The distribution of corrected visual acuity did not vary by colour vision status ( 2 trend, P = 0.12). Birthweight, social class at birth, family size, and parental education, all associated with education, were accounted for in the present analysis, although not associated with CVD. At 7 years, CVD and mathematics and reading scores were not significantly associated, after adjustment for age at testing and factors described above (table). At 16, after additional adjustment for prior test scores, children with CVD scored higher than those without; but the small differences, although statistically significant, were functionally unimportant (0.08 standard deviations; 0.002 to 0.16; P = 0.05 for mathematics and 0.07; 0.002 to 0.14; P = 0.04 for reading). There were no significant differences, by colour vision status, for boys or girls, in scores for "copy a design" or "draw a man" at 7 years. Highest educational qualification and colour vision status were not associated for either men or women ( 2 trend, P = 0.07 and P = 0.61). Risk of unintentional injury did not differ significantly (table). Overall, 8.9% (8.2% to 9.6%) of females and 19.2% (18.2% to 20.2%) of males had road injuries as a driver by 33 years; people with CVD reported fewer unintentional injuries (P = 0.08 and P = 0.05). At 33 years, 30% (28.9% to 31.2%) of men reported unintentional injuries in the workplace, without any increased risk in those with colour vision defects (P = 0.293).

Unintentional injuries in school-aged children and adolescents: lessons from a systematic review of cohort studies

“…Being taller and heavier than their peers was an independent risk factor for fractures in children from New Zealand,39 while post-primary school UK boys were more likely to sustain road traffic injuries if of short stature 40. The latter study also reported increased risk of traffic injuries with sensory deficit (unspecified), in contrast with papers reporting no increased risk of any injury associated with colour vision deficit41 or amblyopia 42. Studies exploring the impact of poor coordination or motor development found little evidence of independent increased risk in cohorts from both the UK40 and New Zealand 43…”

Subjects with colour vision deficiency in the community: what do primary care physicians need to know?

“…In contrast, a 2004 cohort study on 499 CVD children found that CVD did not cause significantly lower scores in mathematics and reading at 7 years and 16 years of age respectively, even after adjusting for birth-weight, social class at birth, family size, and parental education [21]. Furthermore, the highest educational qualification was not significantly associated with colour vision status [21]. Another 2004 questionnaire survey showed no significant difference in the disciplines studied between NCV and CVD persons, but CVD interviewees tended towards technical studies (30%, as opposed to 18% of NCV subjects), and less of them undertook tertiary education in university (68.9%, as opposed to 79.9% of NCV subjects) [22].…”

“…A subsequent study in 1998 showed significantly lower general academic scores among 82 children with CVD as compared to 82 children with NCV, matched by age and class [20]. In contrast, a 2004 cohort study on 499 CVD children found that CVD did not cause significantly lower scores in mathematics and reading at 7 years and 16 years of age respectively, even after adjusting for birth-weight, social class at birth, family size, and parental education [21]. Furthermore, the highest educational qualification was not significantly associated with colour vision status [21].…”

“…Deutans caused more accidents than NCV drivers at traffic light controlled intersections, although this was not statistically significant [36]. A case control study also showed that there was no increased risk of unintentional workplace injuries amongst CVD subjects [21].…”

“…In terms of accident rates, studies reported that CVD drivers did not have more road traffic accidents than NCV drivers [21,22,36,42]. However, protans showed significantly more rear end collisions and accidents by overlooking red rear, stop and warning lights than colour normal [36].…”