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Open Access 01-12-2015 | Update

Statistical analysis plan for the Laser-1st versus Drops-1st for Glaucoma and Ocular Hypertension Trial (LiGHT): a multi-centre randomised controlled trial

Authors: Victoria Vickerstaff, Gareth Ambler, Catey Bunce, Wen Xing, Gus Gazzard, on behalf of the LiGHT Trial Study Group

Published in: Trials | Issue 1/2015

Abstract

Background

The LiGHT trial (Laser-1st versus Drops-1st for Glaucoma and Ocular Hypertension Trial) is a multicentre randomised controlled trial of two treatment pathways for patients who are newly diagnosed with open-angle glaucoma (OAG) and ocular hypertension (OHT). The main hypothesis for the trial is that lowering intraocular pressure (IOP) with selective laser trabeculoplasty (SLT) as the primary treatment (‘Laser-1st’) leads to a better health-related quality of life than for those started on IOP-lowering drops as their primary treatment (‘Medicine-1st’) and that this is associated with reduced costs and improved tolerability of treatment. This paper describes the statistical analysis plan for the study.

Methods/Design

The LiGHT trial is an unmasked, multi-centre randomised controlled trial. A total of 718 patients (359 per arm) are being randomised to two groups: medicine-first or laser-first treatment. Outcomes are recorded at baseline and at 6-month intervals up to 36 months. The primary outcome measure is health-related quality of life (HRQL) at 36 months measured using the EQ-5D-5L. The main secondary outcome is the Glaucoma Utility Index. We plan to analyse the patient outcome data according to the group to which the patient was originally assigned. Methods of statistical analysis are described, including the handling of missing data, the covariates used in the adjusted analyses and the planned sensitivity analyses.

Trial registration

The trial was registered with the ISRCTN register on 23/07/2012, number ISRCTN32038223.

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Title: Statistical analysis plan for the Laser-1st versus Drops-1st for Glaucoma and Ocular Hypertension Trial (LiGHT): a multi-centre randomised controlled trial
Authors: Victoria Vickerstaff
Gareth Ambler
Catey Bunce
Wen Xing
Gus Gazzard
on behalf of the LiGHT Trial Study Group
Publication date: 01-12-2015
Publisher: BioMed Central
Published in: Trials / Issue 1/2015
Electronic ISSN: 1745-6215
DOI: https://doi.org/10.1186/s13063-015-1047-9

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Statistical analysis plan for the Laser-1st versus Drops-1st for Glaucoma and Ocular Hypertension Trial (LiGHT): a multi-centre randomised controlled trial

Abstract

Background

Methods/Design

Trial registration

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Background

Methods/Design

Trial registration

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