Pass a JavaScript function as parameter

You just need to remove the parenthesis:

addContact(entityId, refreshContactList);

This then passes the function without executing it first.

Here is an example:

function addContact(id, refreshCallback) {
    refreshCallback();
    // You can also pass arguments if you need to
    // refreshCallback(id);
}

function refreshContactList() {
    alert('Hello World');
}

addContact(1, refreshContactList);