Clinical Trial Site Network

This is a visualization of the network formed by the sites selected for a portfolio of clinical trials. The graph serves to highlight the interconnectedness of the sites involved in clinical research.

A single click on any node will highlight it and its label. A double-click will return it to its original format. Names of the trials and the sites are anonymized.

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <style>
        path.link {
            fill: none;
            stroke: #666;
            stroke-width: 1.5px;
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            font: 10px sans-serif;
            pointer-events: none;
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        section {
            margin-left: auto;
            margin-right: auto;
        }
    </style>
</head>
<body>
    <script src="https://d3js.org/d3.v3.min.js"></script>
    <script>
        d3.csv("EdgeList.csv", function (error, links) {
            var nodes = {};

// Compute the distinct nodes from the Edge List
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                .linkDistance(45)
                .charge(-300)
                .gravity(0.9)
                .on("tick", tick)
                .start();

var svg = d3.select("body").append("svg")
                .attr("width", width)
                .attr("height", height);

// build the arrow.
            svg.append("svg:defs").selectAll("marker")
                .data(["end"]) // Different link/path types can be defined here
                .enter().append("svg:marker") // This section adds in the arrows
                .attr("id", String)
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                .attr("refX", 15)
                .attr("refY", -1.5)
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https://d3js.org/d3.v3.min.js