Since the method is a static, one practice is using it to check whether a specific server database driver is available and configured correctly with PDO before establishing the connection:
<?php
try {
    if (!in_array("mysql",PDO::getAvailableDrivers(),TRUE))
    {
        throw new PDOException ("Cannot work without a proper database setting up");
    }
}
catch (PDOException $pdoEx)
{
    echo "Database Error .. Details :<br /> {$pdoEx->getMessage()}";
}
?>
 
or to check for any driver in general: 
<?php
if (empty(PDO::getAvailableDrivers()))
    {
        throw new PDOException ("PDO does not support any driver.");
    }
?>