In the context of PHP functions, what are best practices for handling return values and ensuring they are properly utilized?

When creating PHP functions, it is important to ensure that return values are properly handled and utilized to avoid potential bugs or unexpected behavior in your code. One best practice is to always check the return value of a function before using it, to ensure it is not null or false. Additionally, it is a good practice to provide clear documentation for the return values of your functions to help other developers understand how to use them effectively.

// Example of a function that checks and properly utilizes the return value

function getUserData($userId) {
    // Retrieve user data from database
    $userData = getUserDataFromDatabase($userId);

    // Check if user data was successfully retrieved
    if ($userData) {
        // Process the user data
        processUserData($userData);
    } else {
        // Handle error or return default value
        return 'User data not found';
    }
}