Children who don't respond to antidepressant medication showed which of the following? additional improvement when CBT was added to their treatment, and the added benefits were still present at $24-$week follow$-$up no additional improvement when CBT was added to their treatment initially, though some gains were seen at the $24-$week follow$-$up no additional improvement when CBT was added to their treatment additional improvement when CBT was added to their treatment, though the added benefits were no longer present at $24-$week follow$-$up