Official ESCRS | European Society of Cataract & Refractive Surgeons

Methodological limitations in published multifocal intraocular lens randomized controlled trials

Session Details

Session Title: Cataract 2
Session Date/Time: Saturday 21/02/2015 | 08:30-11:00
Paper Time: 09:57
Venue: Hall 1
First Author: : F.Esen TURKEY
Co Author(s): :    E. Kucukkomurcu   A. Er   S. Akkaya-Turhan   E. Toker     

Abstract Details


We had the observation that some of the multifocal intraocular lens (MF-IOL) randomized controlled trials (RCT) lacked some basic methodological information and it made it very hard to compare the results of different MF-IOL RCTs. The purpose of this study was to formally tabulate a certain set of methodological limitations in the published multifocal intraocular lens (MF-IOL) randomized controlled trials (RCT).


We did a PubMed search with the term “Multifocal intraocular lenses” and limitations “randomized controlled trials, humans”. The PubMed search yielded 52 articles, we could reach 45 of them and 37 articles qualified for the survey.


We only included RCTs where the aim of the study was to evaluate the performance of a MF-IOL. We did not include meta-analyses or secondary analyses of previous RCTs. Two independent observers (EK, AE) read through each article and searched for the presence of distance (DVA), near (NVA) and intermediate visual acuity (IVA); the presence of correction with glasses and evaluation of contrast sensitivity. When there was a disagreement between the two authors (%9.16 of the cases), tree authors came together (FE, EK and AE) and solved the disagreements by discussion.


DVA was given monocularly in 8 studies (22.2%), binocularly in 10 studies (27.8%), and both in 7 studies (19.4%). In 10 studies it was not mentioned whether DVA was monocular or binocular. IVA was only evaluated in 12 of the studies (32.4%). NVA was evaluated in 33 studies (89.2%) and in 9 of them (24.3%) it was not mentioned whether the reported NVA was binocular or monocular. In one of the studies it was not mentioned whether DVA was corrected or not. Contrast sensitivity was evaluated in 20 studies (54.1%) and glare was evaluated only in 5 studies (13.5%).


In many cases it is impossible to compare the results of different MF-IOL RCTs, because of missing methodological information or data. We were surprised to observe that in 27.8% of RCTs published in high impact factor journals, lacked the information whether the reported visual acuity was monocular or binocular. While IVA is becoming more important with modern lifestyle, there was no data on IVA in 67.6% of the published RCTs. In 75% of the contrast sensitivity studies, the influence of glare was not studied. We reason that more awareness of these methodological limitations should improve the quality of future work.

Financial Disclosure:


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