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Fitting success for three multifocal designs: Multicentre randomised trial
Emilia Novillo-Díaz1, César Villa-Collar2, Mónica Narváez-Peña3
1María Cristina Optometry Center, Tomelloso, Ciudad Real, Spain.
Purpose:
To determine if the discontinuation of commercially-available simultaneous vision Multifocal Soft Contact Lenses is independent from the multifocal design. To determine causes for discontinuation and psychosocial factors involved.
Methods:
Multicentre single-blinded randomised controlled trial with external blinded evaluation for a three months follow-up period for three intervention groups. 150 single-vision soft wearers were randomly assigned a spherical near centred lens (S-CN), distance centred lens (CD) or aspherical near centred lens (A-CN). Cases of discontinuation, anxiety and quality of life were measured at one week and one month.
Results:
120 females and 30 males were included with an age range of 40-62 (48.79 ± 5.23). At one month, the S-CN design had a statistically significant higher risk of discontinuation than the other two OR: 6.12 (95%CI 2.5-14.9). Twenty-eight subjects discontinued wearing S-CN at first week (56%), while discontinuation of CD and A-CD were 15 (30%) and 11 (22%), with a statistically significant difference between S-CN design and the other two (p = 0.001). There were not statistically significant differences when direct comparison between discontinuation of CD and A-CN was made (p = 0.36). Thirty-two percent discontinued the use because of poor distance vision and 28% because of both poor distance and near vision. Psychosocial factors were not statistically significant.
Conclusions:
Discontinuation of Multifocal Soft Contact Lenses is dependent on the design. Most common cause for discontinuation is poor distance vision. Psychosocial factors do not impact on discontinuation rates.
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