JSFiddle - React, Tailwind, and code Playground
HTML
<link rel="stylesheet" href="http://cdn.poluza.com/media/css/c1807117763-c2NyZWVu.css">
<form>
<div id="buttons">
<input name="radio" type="radio" id="edit-option-1" required value="1">
<label for="edit-option-1">Option 1</label>
<input name="radio" type="radio" id="edit-option-2" required value="2">
<label for="edit-option-2">Option 2</label>
</div>
<input type="submit" value="Submit">
</form>
JavaScript
$('#buttons').buttonset();
$('form').submit(function (event) {
// 0 in IE7
// 1 in Chrome, Firefox, Safari, Konqueror (with WebKit engine), IE8, IE9
// IE10 will instead block this function from running as the validity check runs first due to the required attribute http://i.imgur.com/NEE5d.png
alert($('input[type="radio"]:checked').size());
event.preventDefault();
return false;
});