In my survey I have a constant sum matrix table with 2 columns and the total for the 2 columns must equal the value given for a previous question, e.g.:

question_0: how many items did you buy? ; answer_0 = 10

question_1:

I only want to allow the survey to progress when e + f = 10. I think the default sum validation can only look at e and f individually and check if these equal 10?

I have added some JavaScript inside the addOnPageSubmit method and I can return a browser alert when the totals don’t match, but the survey still progresses to the next page when the alert is dismissed.

Is there anything I am doing wrong, or missing?

Thanks!

Qualtrics.SurveyEngine.addOnPageSubmit(function() {
    // Function to validate the totals
    function validateTotal() {
        // Retrieve the embedded data field value
        const s17_01 = parseFloat('${e://Field/s17_01}');

        // Retrieve the values entered by the respondent
        const inPatientTotal = parseFloat(document.getElementById('QID40~1_Total').value) || 0;
        const outPatientTotal = parseFloat(document.getElementById('QID40~2_Total').value) || 0;

        // Calculate the combined total
        let allPatientTotal = inPatientTotal + outPatientTotal;

        // Check if the totals match
        if (s17_01 !== allPatientTotal) {
            // Show an alert if the totals do not match
            alert('Totals are not correct.');
            return false; // Return false to prevent page submission
        }
        return true; // Return true if the totals match
    }

    // Check the result of validateTotal before submitting the page
    if (!validateTotal()) {
        // Prevent page submission if validation fails
        return false;
    }
});