This answer still seems to be getting a few hits so I thought I'd add a link to a new page I stumbled across which may help create cron commands: https://crontab.guru
The other advantage of using curl is that you also can keep the HTTP way of sending parameters to your script if you need to, by using $_GET, $_POST etc like this:
*/5 * * * * curl --request GET 'http://exemple.com/path/check.php?param1=1¶m2=2'
Using -O parameter like the above means that the output of the web request will be sent to STDOUT (standard output).
And the >/dev/null 2>&1 will instruct standard output to be redirected to a black hole. So no message from the executing program is returned to the screen.