# Customised format floating itemized list

I'd like to add floating itemized lists in a format illustrated below:

More specifically, I would like

1. The title above rather than below the float, with bold font for title and horizontal line beneath
2. No bullets
3. First level items italicised, no indent; Second level items Roman, no indent; Third level items Roman; indented one tab stop; with a blank line of space between groups of first level items
4. Also, if in a two column formatted document, the list is to only occupy one column of the document

Ideally, I'd like to set up all the formatting in the preamble, then whenever I have a floating list of this type to insert, I could just create it by listing the \items in a similar way to making a regular itemized list.

I suspect it is possible to do this using \table, but will be rather long-winded.

Is it possible to customise the \itemize command to easily produce floating lists of this type?

Is there an add-in package which is like \itemize but has greater options for customisation, that might be able to produce a list of this type?

I don't think you need itemized lists, but a (modified) tabular environment.

\documentclass{article}
\usepackage{booktabs,caption}
\captionsetup[table]{position=top}

\newcommand{\category}{%
\global\startedtrue
\global\categorytrue
\itshape}
\newif\ifstarted
\newif\ifcategory
\newenvironment{itemtabular}
{\global\startedfalse\global\categoryfalse\tabular}
{\endtabular}

\begin{document}
\begin{table}
\centering
\caption{Low tidal volumes in pressure preset modes}
\begin{itemtabular}{@{}l@{}}
\toprule
\category Patient factors \\
\main Asynchronous breathing \\
\main Decreased compliance \\
\sub Development of pneumothorax \\
\sub Pulmonary pathology \\
\category Equipment causes \\
\main Ventilator settings\\