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Patient-reported quality of life and eligibility for cataract surgery: assessing the relationship between ethnicity and ‘Impact on Life’ questionnaire scores in New Zealand

N Z Med J. 2022 Apr 14;135(1553):19-26.


AIMS: The ‘Impact on Life’ (IoL) questionnaire is a patient reported quality-of-life assessment tool used to prioritise cataract surgery in New Zealand (NZ). This study evaluated the association between ethnicity and IoL questionnaire responses.

METHODS: This is a retrospective cohort study of patients prioritised for public-funded cataract surgery between November 2014 and March 2019 in New Zealand. Data were extracted from the New Zealand Ministry of Health National Prioritisation Web Service database. Ethnic, demographic and IoL data for all patients who were prioritised for surgery were analysed after controlling for age, gender, visual acuity and cataract type.

RESULTS: Of the 58,648 prioritisation events, over the four-and-a-half-year period, 46,352 prioritisation events had documented scores for the IoL questionnaire. The study population had a mean age of 74.4 years and had a female preponderance (74%). The average IoL score was 22.5/36 (SD 7.8). After controlling for age, gender, visual acuity (VA) and cataract type, there was only a marginal difference between Māori and non-Māori IoL scores (22.8/36 vs 22.4/36) despite statistical significance for the difference (p=0.001). Māori and Pacific people presented at a younger age (68.5 years and 66.7 years, respectively) with worse visual acuity than other ethnic groups (mean range 70.1-76.7 years). Mean IoL scores were 23.0/36 for Māori and Pacific people and 22.4/36 for other ethnic groups.

CONCLUSIONS: Māori and Pacific people present younger with worse VA and more advanced cataracts at time of surgical prioritisation when compared with other ethnic groups. Despite these differences, after controlling for confounding factors, the mean IoL score did not differ to a level that was clinically significant between different ethnic groups in New Zealand at time of prioritisation for cataract surgery. These results suggest that there are no meaningful ethnic specific differences in patient reported quality of life for patients with cataract in New Zealand after controlling for other factors. Alternatively, the IoL tool may lack the sensitivity to detect meaningful ethnic disparities that may exist for quality of life in this cohort of patients.


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