Not really an easy way of doing it, depends on your design really. One simple method (as an example) might be something like...
// get database results.
while ($row = mysql_fetch_array($result)) {
switch ($SESSION['level']) {
case 'admin':
echo $row[0]." ".$row[1]." ".$row[2];
break;
case 'user':
echo $row[0]." ".$row[1];
break;
default:
echo "sorry, you need to be a user or admin to view these results";
}
}