An optometrist will not only have multiple tests (color plates, colored objects to put in order) but will also have the correct environment (amount of light, type of light) to properly illuminate the test. The Farnsworth Lantern (FALANT) test, according to my optometrist, is notorious for inaccurate administration - most fluorescent lighting emits the "wrong" color spectrum to enable picking out the dots.
My "failure" of the FALANT decades ago was never questioned, became part of my permanent medical record, and closed a number of career options "You can't see color? You'll never be a pilot (electrician, EOD tech...)"
A smart optometrist opened my eyes, so to speak, when he showed me how the test should be conducted; I'm not color deficient at all! That said, I reserve the right to ascribe fashion faux pas to any source that comes to mind...