If your condition is going to be predictably in a numerical range like that, this may work.

if($variable >= $lower_limit && $variable <= $upper_limit)
{
miraculous_stuff;
}
[download]

If your requirement is to do something when $variable is an integer, vs something else when it isn't, or when $variable is being tested against values in an array, this probably would not be appropriate, but if it's a regular as what I read at 10:46pm EST 14 Dec 2005, my suggestion may be appropriate.