Official ESCRS | European Society of Cataract & Refractive Surgeons


Microinvasive glaucoma surgery: compliance with the World Glaucoma Association Guidelines on Design and Reporting of Glaucoma Surgical Trials

Search Title by author or title

Session Details

Session Title: Ocular Pathology/Education & Training

Session Date/Time: Tuesday 17/09/2019 | 14:00-16:00

Paper Time: 15:18

Venue: Free Paper Forum: Podium 4

First Author: : Y.Buys CANADA

Co Author(s): :    D. Mathew   B. McKay   A. Basilious   A. Belkin   G. Trope                 

Abstract Details


Advancement in glaucoma surgical procedures has been impeded by a lack of uniform study designs including methodology, ethical considerations and outcome measures. To address these inconsistencies in 2009 the World Glaucoma Association (WGA) published Guidelines on Design and Reporting of Glaucoma Surgical Trials. This study aims to evaluate the adherence of published clinical trials involving MIGS to the WGA Guideline.


Published comparative trials involving MIGS in the peer-reviewed literature from January 1, 2000 to June 21, 2018.


Using a predefined search strategy, the following databases were searched for comparative trials involving MIGS in the English peer-reviewed literature from January 1, 2000 to June 21, 2018: Medline, EMBASE, BIOSIS, Cochrane and Web of Science. From the WGA Guidelines, 53 outcomes were selected for evaluation: methodology (31), definition of success (7), ethics (10), postoperative complications (1), economic evaluation (1) and statistical reporting (3). Each article was assessed by two reviewers; differences were resolved by consensus. The proportion of outcomes adhering to the Guidelines was determined. In addition, the adherence of randomized controlled trials (RCTs) was compared to non-RCTs.


Twenty-five publications were identified; 10 RCTs and 15 non-RCTs. Mean number of outcomes adhering to the WGA guidelines was 24.2±6.1 (45.6% compliance): 28.0±6.2 (52.8%) and 21.6±4.7 (40.8%) for RCT and non-RCT, respectively (p=0.01). Mean percent compliance for each subsection were: methodology-48.8%; definition of success-21.1%; ethics-55.6%; complications-88%; economic evaluation-0%; and statistics-37.3%. There was a significant difference in adherence between RCTs and non-RCTs for 16 outcomes. 'Better' outcomes for non-RCTs included providing an IOP survival curve (47% vs 0%), not industry-funded (100% vs 10%), no authors being shareholders (86.7% vs 40%) and no industry employee authors (100% vs 40%).


Interpreting results of clinical trials involving MIGS is a challenge due to inconsistency in study designs, outcome measures and reporting of results. In addition, significant conflicts of interest were identified that increase the risk of bias. Overall, published comparative MIGS trials show low adherence (45.6%) to the WGA guidelines. Utilising standardised methodology and reporting of results and having a publicly available registry of study protocols with complete data on the individual outcomes collected during the study would greatly enhance interpretation and transparency of study outcomes and facilitate comparisons between trials. Authors and journals should be encouraged to follow the WGA guidelines.

Financial Disclosure:


Back to previous