Criteria for prescribing optometric interventions: literature review and practitioner survey

Abstract

The core function of optometrists is the prescribing of refractive corrections, yet a literature review revealed a lack of evidence‐based research on criteria for determining when a refractive correction is required. The reported criteria used by practising optometrists were investigated using a questionnaire to survey prescribing habits for borderline hypermetropia, presbyopia, astigmatism, and horizontal and vertical heterophoria. Thirty‐eight questionnaires were returned and the results analysed. We calculated the ‘cut off’ point above which the anomaly would be corrected over 50% of the time that it was encountered. There was a large variation for each category, but it was clear that the presence or absence of symptoms was an important factor for most optometrists when deciding whether to correct a small error. It was found that for symptomatic patients, most optometrists would correct an anomaly if it reached: +1.00 D of hypermetropia, a reading addition of +0.75 D for presbyopia, −0.75 DC of astigmatism, 1.5 prism dioptres (Δ) of horizontal aligning prism, and 1 Δ of vertical dissociated heterophoria. For asymptomatic patients, optometrists would not correct any of the hypermetropic anomalies or heterophorias that were specified in our questionnaire. However most would correct a presbyopic error of +1.50 D or above, or an astigmatic error of −1.50 DC or above, even in the absence of symptoms. These results were compared with previously published guidelines.