Display Sub-categories in a Simple List

Hello ... I'm trying to output a simple list of categories but am having a bit of trouble. I've followed Chris's sub-category tutorial (http://www.interactivetools.com/forum/gforum.cgi?post=77230) successfully for other outputs, but can't get this to work.

I have a list of businesses and individuals that fall into one of 9 categories. My desired output is as follows:

Category 1
- business 1
- business 2
- business 3

Category 2
- business 4
- business 5
- business 6

Category 3
- business 7
- business 8
- business 9
- business 10

etc.

But when I output my list each member appears in every category, as in:

Category 1
- business 1
- business 2
- business 3

Category 2
- business 1
- business 2
- business 3

etc.

I know this is a simple coding issue. Here is what I have in my file:

HEAD

// load viewer library
$libraryPath = 'cmsAdmin/lib/viewer_functions.php';
$dirsToCheck = array('/home/tucg/public_html/','','../','../../','../../../');
foreach ($dirsToCheck as $dir) { if (@include_once("$dir$libraryPath")) { break; }}
if (!function_exists('getRecords')) { die("Couldn't load viewer library, check filepath in sourcecode."); }

list($categoriesRecords, $selectedCategory) = getCategories(array(
'tableName' => 'categories',
'categoryFormat' => 'onelevel',
));

list($participantsRecords, $participantsMetaData) = getRecords(array(
'tableName' => 'participants',
));


BODY

<?php foreach ($categoriesRecords as $categoryRecord): ?>
<h2><?php echo $categoryRecord['name'] ?></h2>
<ul>
<?php if ($categoryRecord['num']): ?>

<?php foreach ($participantsRecords as $record): ?>
<li><?php if ($record['url']): ?><a href='http://<?php endif ?>
<?php echo $record['url'] ?><?php if ($record['url']): ?>' target='_blank'><?php endif ?><?php echo $record['title'] ?>
<?php if ($record['url']): ?></a><?php endif ?>
<span class="contact-info"><?php echo $record['phone_number'] ?></li>
<?php endforeach ?>

<?php endif ?>
</ul>

<?php endforeach ?>
</ul>

Any help would be appreciated.
Many thanks,

Chris P