ARMD

These are the data of a clinical trial involving patients suffering from age-related macular degeneration (ARMD), a condition that involves a progressive loss of vision. A total of \(181\) patients from \(36\) centers participated in the trial. Patients' visual acuity was assessed using standardized vision charts. There were two treatment conditions (placebo and interferon-\(\alpha\)). The potential surrogate endpoint is the change in the visual acuity at \(24\) weeks (\(6\) months) after starting treatment. The true endpoint is the change in the visual acuity at \(52\) weeks.

In a clinical trial, it frequently occurs that the most credible
outcome to evaluate the effectiveness of a new therapy (the true endpoint) is
difficult to measure. In such a situation, it can be an effective strategy to
replace the true endpoint by a (bio)marker that is easier to measure and that
allows for a prediction of the treatment effect on the true endpoint (a
surrogate endpoint). The package 'Surrogate' allows for an evaluation of the
appropriateness of a candidate surrogate endpoint based on the meta-analytic,
information-theoretic, and causal-inference frameworks. Part of this software
has been developed using funding provided from the European Union's Seventh
Framework Programme for research, technological development and demonstration
(Grant Agreement no 602552), the Special Research Fund (BOF) of Hasselt
University (BOF-number: BOF2OCPO3), GlaxoSmithKline Biologicals, Baekeland
Mandaat (HBC.2022.0145), and Johnson & Johnson Innovative Medicine.

Wim der Elst

Surrogate

Evaluation of Surrogate Endpoints in Clinical Trials

Wim Van Der Elst

Florian Stijven

Fenny Ong

Dries De Witte

Paul Meyvisch

Alvaro Poveda

Ariel Alonso

Hannah Ensor

Christoper Weir

Geert Molenberghs

ARMD function

A <code>data.frame</code> with \(181\) observations on \(5\) variables.<dl>
 <dt><code>Id</code></dt>
<dd>The Patient ID.</dd> <dt><code>Center</code></dt>
<dd>The center in which the patient was treated.</dd> <dt><code>Treat</code></dt>
<dd>The treatment indicator, coded as \(-1\) = placebo and \(1\) = interferon-\(\alpha\).</dd> <dt><code>Diff24</code></dt>
<dd>The change in the visual acuity at \(24\) weeks after starting treatment. This endpoint is a potential surrogate for <code>Diff52</code>.</dd> <dt><code>Diff52</code></dt>
<dd>The change in the visual acuity at \(52\) weeks after starting treatment. This outcome serves as the true endpoint.</dd> 
</dl>

Format

Data of the Age-Related Macular Degeneration Study — ARMD

A <code>data.frame</code> with \(181\) observations on \(5\) variables.<dl>
 <dt><code>Id</code></dt>
<dd>The Patient ID.</dd>

 <dt><code>Center</code></dt>
<dd>The center in which the patient was treated.</dd>

 <dt><code>Treat</code></dt>
<dd>The treatment indicator, coded as \(-1\) = placebo and \(1\) = interferon-\(\alpha\).</dd>

 <dt><code>Diff24</code></dt>
<dd>The change in the visual acuity at \(24\) weeks after starting treatment. This endpoint is a potential surrogate for <code>Diff52</code>.</dd>

 <dt><code>Diff52</code></dt>
<dd>The change in the visual acuity at \(52\) weeks after starting treatment. This outcome serves as the true endpoint.</dd>

 
</dl>

Data of the Age-Related Macular Degeneration Study

ARMD: Data of the Age-Related Macular Degeneration Study

Description

Usage

Arguments

Format