Source: wikibot/holmgren-s-wool-test
= Holmgren's wool test
{wiki=Holmgren's_wool_test}
Holmgren's wool test is a diagnostic test used to assess color vision deficiency, particularly in relation to red-green color blindness. It was developed by the Swedish ophthalmologist Alarik Holmgren in the late 19th century. In the test, the subject is presented with a set of colored wool strands, typically in various shades of green and red, and is asked to sort them into piles based on color.