Adherence to myopia control spectacle lens wear in children aged 7 to 12: a comparison of two lens designs.

Participants aged 7-12 with myopia will be assigned to wear one of two types of myopia control spectacle lenses for one year, either Defocus Incorporated Multiple Segment (DIMS) or Highly Aspheric Lenslet Target (HALT) lenses. The aims of this study are to measure and compare adherence to the treatment between the DIMS and HALT groups, monitor adaptation and to identify barriers to full time wear. Participants will attend 6 visits (each 30 to 90 minutes long) at the University of Auckland Eye Clinic at the Faculty of Medical and Health Sciences over a one year period. The visits will occur at Baseline, 2 weeks after baseline for spectacle collection, 1 month, 6 months, 7 months and 12 months from spectacle collection. Visit 1 (60 minutes): Baseline/Dispensing appointment. The dispensing appointment will occur after a baseline eye examination (as part of the patient's routine optometric care). The participant will choose a frame and the measurements necessary to manufacture the DIMS or HALT lenses will be taken (monocular centration distances using a pupilometer and vertical heights using a pen torch and ruler. The parent or guardian will be asked to complete a questionnaire to obtain information on the history of spectacle wear. Axial lengths and the spectacle prescription will be retrieved for the participants clinical records with consent. Visit 2 (30 minutes): Spectacle Collection. Participant will collect the glasses 2 to 3 weeks after visit 1 and visual acuities will be assessed using a Snellen chart a 6 metres and near vision chart. Lens centration over the pupil will be assessed and frame adjustments will be made where necessary. Visit 3 (30 minutes): 1 month from spectacle collection. The parent or guardian will be asked to complete a questionnaire on spectacle adherence, adaptation to the lens design and factors preventing full-time wear. Spectacle fitting will be assessed and frames will be adjusted or repaired where necessary. Visit 4 (60 minutes): 6 months from spectacle collection. This appointment will follow the patient's routine 6 month eye examination. The parent or guardian will complete a questionnaire on spectacle adherence, adaptation to the lens design and factors preventing full time wear. Visual acuities will be measured using a Snellen chart at 6m and a near vision chart, and lens centration over the pupil will be assessed. Frame adjustments will be made where necessary. Axial lengths and the spectacle prescription will be obtained from the patient's clinical records. A SpecsOn temperature device will be fixed to the frame and will be used over the next 3 weeks to sample adherence to the treatment. This device is a non-invasive, non-emitting electronic device that measures skin and ambient temperature. The temperature differential will be used to determine when the glasses are being worn. Visit 5 (30 minutes): 3 weeks from visit 4. This appointment is for the removal of the SpecsOn temperature sensor. Data will be retrieved from the device and the participant will wear the glasses without the sensor for the rest of the study. Spectacle fitting will be assessed and frame adjustments or repairs will be made where necessary. Visit 6 (60 minutes): 12 months from spectacle collection. This appointment will follow the patient's routine 12 month eye examination. The parent or guardian will complete a questionnaire on spectacle adherence, adaptation to the lens design and factors preventing full time wear. Visual acuities will be measured using a Snellen chart at 6 metres and a near vision chart, and lens centration over the pupil will be assessed. Frame adjustments will be made where necessary. Axial lengths and the spectacle prescription will be obtained from the patient's clinical records. Parents or guardians will be asked to report the number of hours their wears their glasses on 10 separate days spread throughout the year, 5 days during school holidays and 5 days during term time. Parents or guardians will be asked to report the number of hours via an online form and will be notified the day before the form is sent. A Dispensing Optician will dispense the spectacles, administer the questionnaires and collect adherence and adaptation data. The spectacle prescription and axial lengths will be measured during routine eye examinations at the University of Auckland Eye Clinic and this data will be retrieved from the patient record with consent.