Eliminating unwanted nag message

Is it possible to prevent the "You haven't read...." message (or some such thing) displaying books opened but not recently read? Of course, one can simply ignore the pop up box and deselect the checked books, or individually mark book(s) as unread or finished. I would like to avoid the nag box entirely. Can something be inserted in the .conf file or is the message part of the bundled reading stats?