Hide category in admin view

Hi all. Hope you are all well.

I was wanting to know if it is possible to hide certain categories in the “Recent Activity” section of the admin panel within WordPress.

I use WordPress as a CMS and I post a few comments/posts that I don’t need a lot of my authors or contributors to see. Is this possible. I think I know where to look but I am not sure what to put in…

Any suggestions?! Thanks muchly…

Andy
PS I’ve been looking in the index file within the admin folder of my install. More specifically at the following code:

<?php
if ( $recentposts = $wpdb->get_results("SELECT ID,
post_title FROM $wpdb->posts WHERE post_type =
'post' AND post_status = 'publish' AND
post_date_gmt < '$today' ORDER BY post_date
DESC LIMIT 5") ) :
?>

I want to insert something along the lines of AND post_category NOT =’x’ or something but can’t make that work. My SQL knowledge isn’t great so sorry if this is a foolish suggestion… I am getting better!