Development and validation of the first Canadian Aboriginal syllabics visual acuity chart.

OBJECTIVE

To design and validate the first visual acuity (VA) chart in the Canadian Aboriginal syllabics (CAS) alphabet.

DESIGN

Prospective, nonrandomized, within-subjects cross-sectional study.

PARTICIPANTS

Twenty Latin- and CAS-reading subjects were recruited from Ullivik, a residence in Montreal for Inuit patients.

METHODS

VA charts were made in Latin and in CAS using letters conserved across Inuktitut, Cree, and Ojibwe languages. Fonts were similar in style and size between charts. Each chart was made for a viewing distance of 3 m, with 11 lines of VAs from 20/200 to 20/10. Charts were created using LaTeX to ensure proper formatting and optotype sizing and displayed to scale on an iPad Pro. Each participant had his or her best-corrected VA for each eye measured using the Latin and CAS charts sequentially for a total of 40 eyes.

RESULTS

Median best-corrected VAs were 0.04 logMAR (range, -0.06-0.54) and 0.07 logMAR (range, 0-0.54) for the Latin and CAS charts, respectively. Median difference between CAS and Latin charts was 0 logMAR (range, -0.08-0.1). Mean ± SD difference between charts was 0.01 ± 0.03 logMAR. Pearson's r correlation between groups was 0.97. The two-tailed paired t test between groups was p = 0.26.

CONCLUSIONS

We demonstrate here the first VA chart in Canadian Aboriginal syllabics for Inuktitut-, Ojibwe-, and Cree-reading patients. The CAS VA chart has highly similar measurements to the standard Snellen chart. Testing VA for Indigenous patients in their native alphabet may provide patient-centred care and accurate VA measurements for Indigenous Canadians.