Something

class survey_field_radio extends eSurvey_field
{
	function show_form_field($field)
	{
		global $frm;		
		$p = $this->field_parms($field);
		$options=explode(",", $field['field_choices']);
		$sep = ($field['field_type'] == 4 ? "&nbsp;&nbsp;" : "<br />");
		foreach($options as $o)
		{
			$ch = ($p['value'] == $o) ? 1 : 0;
			$ret .= $frm->form_radio("results[{$p['fn']}]", $o, $ch, "", " {$p['include']} ")."&nbsp;{$o}{$sep}";
		}
		return $ret;
	}
	
	function check_empty($field_num, $value)
	{
		if(!$_POST['results'][$field_num])
		{
			return true;
		}
		return false;
	}
}
eSurvey_field::add_type(4, "survey_field_radio");
eSurvey_field::add_type(17, "survey_field_radio");