Distribution of refractive errors by key socio-demographic factors.

<p>* No qualifications, State school examinations at 16 years of age (‘O’ levels), at 18 years (‘A’ levels) or University/other professional qualification</p><p>Missing data: educational qualification: 1,466 (1.4%), accommodation tenure: 2,102 (2.0%), ethnicity: 779 (0.7%)</p><p>Distribution of refractive errors by key socio-demographic factors.