How to insert an if in a switch case in javascript?

I have this simple javascript function:

function updateDeleteUser(action, userid) {

    frm = document.getElementById("frmsearch");
    frm.frmUserId.value = userid;

    switch (action) {
    case 0:
        frm.action = "UpdateUser.jsp";
        break;
    case 1:
        confirm("Delete account?");
        if (confirm != false){
            frm.action = "DeleteUser.jsp";
        }
    }

    frm.submit();
}

Even if I click on 'NO' the function runs anyway and user gets deleted. What did I do wrong?

Thanks in advance.