Red characters (OGPL)
Where the text uses red characters to highlight the individual characters that form an acronym, capture those letters in a span element with attribute role="acronym".
For other red text, capture it in a span element with attribute role="attention".
Example (role="acronym")
XML
<div1>
<titleGroup><title>
<p>Principles of managing sporting injuries</p></title>
</titleGroup>
<p><list>
<list1>
<item1 id="med-9780199230280-chapter-3-item1-1">
<p>
<enumerator>•</enumerator>
<b>
<i>First aid</i>
</b> (Airway, Breathing, Circulation): Refer severe injuries to
A&E. </p>
</item1>
<item1 id="med-9780199230280-chapter-3-item1-2">
<p>
<enumerator>•</enumerator>
<b>
<i>R I C E</i>
</b>
</p>
<list2>
<item2 id="med-9780199230280-chapter-3-item2-1">
<p>
<enumerator>•</enumerator>
<i>
<span role="acronym">R</span>est</i> Relative rest of affected part whilst
continuing other activities to maintain overall fitness.</p>
</item2>
<item2 id="med-9780199230280-chapter-3-item2-2">
<p>
<enumerator>•</enumerator>
<i>
<span role="acronym">I</span>ce and analgesia</i> Use immediately after
injury (wrap ice in a towel and use for maximum 10min. at a time to prevent
acute cold injury).</p>
</item2>
<item2 id="med-9780199230280-chapter-3-item2-3">
<p>
<enumerator>•</enumerator>
<i>
<span role="acronym">C</span>ompression</i> Taping or strapping can be used
to treat (↓ swelling) and also to prevent acute sprains and
strains.</p>
</item2>
<item2 id="med-9780199230280-chapter-3-item2-4">
<p>
<enumerator>•</enumerator>
<i>
<span role="acronym">E</span>levation</i> ↓ local swelling and
dependent oedema, enabling quicker recovery.</p>
</item2>
</list2>
</item1>
<item1 id="med-9780199230280-chapter-3-item1-3">
<p>
<enumerator>•</enumerator>
<b>
<i>Confirm the diagnosis:</i>
</b> Clinical examination, x-ray.</p>
</item1>
<item1 id="med-9780199230280-chapter-3-item1-4">
<p>
<enumerator>•</enumerator>
<b>
<i>Early treatment:</i>
</b> according to cause. Don’t delay.</p>
</item1>
</list1></list>
</p>
</div1>
Example (role="attention")
XML
<div2 id="med-9780199215683-chapter-3-div2-53">
<titleGroup id="med-9780199215683-chapter-3-titleGroup-97"><title>
<p>
<span role="attention">Tests for vision at 6 weeks:</span>
</p></title>
</titleGroup>
</div2>