如何通过PHP mysqli访问MySQL OUT变量而没有结果集

Question

Is it possible to access an OUT variable from an SP called through mysqli without returning it via SELECT one way or another? I had a good look and tried the code here but it always needs a result set called within or after the SP to work.

Consider this code:

SQL:

DELIMITER $

# DROP PROCEDURE IF EXISTS outVar$

CREATE PROCEDURE outVar(OUT myVar TINYINT(1))
BEGIN

    SET myVar = 1;

END$

DELIMITER ;

CALL outVar(@myVar);

SELECT @myVar;

PHP:

 <?php

    $Conn = new mysqli("127.0.0.1", "root", "123456789", "test");

    $RResult = $Conn->query("CALL outVar(@myVar);");

    print_r($RResult->fetch_assoc());
?>

This returns the following:

Fatal error: Call to a member function fetch_assoc() on boolean in C:\xampp\htdocs\phpTest.php on line 7

Because there are no results returned in tabular form, fair enough. So am I correct in assuming that while OUT is elegant within mysql it's of no use in the mysqli context without the help of a result set leaving OUT redundant in this context? If not I'd love to know how to do it.

Thanks,

James