Apparent skin tone rendering in recommended undergraduate optometric textbooks in England: a descriptive content analysis
A descriptive content analysis of 28 recommended undergraduate optometric textbooks in England reveals a significant underrepresentation of dark skin tones, with only 3.5% of graphics classified as Fitzpatrick types V-VI and half of the textbooks containing no such images at all.
Original paper licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). This is an AI-generated explanation of the paper below. It is not written or endorsed by the authors. For technical accuracy, refer to the original paper. Read full disclaimer
Imagine you are learning to drive. You sit in a classroom, and the instructor hands you a thick manual filled with photos of cars. But here's the catch: every single photo shows a red car. There are no blue, green, or black cars in the book.
If you only ever study red cars, you might get really good at recognizing them. But when you finally get on the road and see a blue car, you might not know what to do. You might not even realize it's a car at all.
This is essentially what Daniela Oehring and her team at the University of Plymouth investigated in their study about optometry textbooks (the books used to train eye doctors) in England.
The Big Question: Who is in the Picture?
The researchers wanted to know: Do the pictures in these textbooks show a mix of skin tones, or do they mostly show light skin?
They looked at 28 different textbooks recommended by universities. They didn't just count pages; they counted 1,623 images (photos and drawings) that showed human skin. They used a standard "skin tone ruler" called the Fitzpatrick Scale, which sorts skin from very light (Type I) to very dark (Type VI).
What They Found: A Very One-Sided Gallery
The results were stark, like walking into a gallery where 99% of the portraits are of the same person.
- The "Light" Majority: About 78% of all the images showed light skin tones.
- The "Dark" Minority: Only 3.5% of the images showed dark skin tones.
- The "Missing" Half: Half of the textbooks (14 out of 28) had zero pictures of dark skin.
- The "Drawing" Problem: This was the most surprising part. While photos sometimes showed a few dark-skinned people, none of the 177 schematic drawings (the line-art diagrams used to explain how the eye works) showed dark skin. They were all drawn with light skin.
To put this in perspective, the researchers compared these numbers to the 2021 UK Census. In the real world, about 19% of the population identifies as non-White. In the textbooks, the number of dark-skinned images was less than 4%.
The "Red Car" Analogy
Think of the textbooks as a recipe book for eye diseases.
- If a disease looks like a red rash on light skin, the book shows a photo of a red rash on light skin.
- But if that same disease looks different on dark skin (maybe it looks purple or doesn't show up as clearly), the book doesn't show that picture.
The authors are careful to say: "We are just describing the pictures; we aren't saying this causes bad eye care yet." They didn't test students to see if they failed exams because of this. However, they note that in other fields (like dermatology), doctors who only study light skin sometimes miss diagnoses on dark skin. They suggest that if optometry textbooks are like those red-car-only manuals, students might be missing out on learning what to look for in a diverse population.
Why the "Drawings" Matter
The fact that the schematic drawings (the made-up illustrations) had no dark skin is significant.
- Photos are limited by who the photographer could find in a hospital.
- Drawings are made by artists. An artist can draw a dark-skinned eye just as easily as a light-skinned one.
- The fact that they didn't suggests it wasn't a "lack of photos" problem; it was a pattern of defaulting to light skin even when the artist had total creative freedom.
The "Ruler" Problem
The authors also admit a limitation in their own study. The "Fitzpatrick Scale" they used was originally designed to measure how easily skin burns in the sun, not to measure how diverse a picture looks. It's like using a ruler designed for measuring wood to measure the softness of a pillow. It works okay, but it's not perfect. They used it only because it's the standard tool other researchers use, so they can compare notes.
The Bottom Line
This study is a snapshot of the current state of eye doctor training materials in England.
- The Finding: The pictures are overwhelmingly light-skinned. Dark skin is rare, and in drawings, it is non-existent.
- The Warning: This pattern is consistent across all the books they checked.
- The Call to Action: The authors aren't suing anyone or saying the books are "illegal." They are simply holding up a mirror and saying, "Look, the pictures in your classroom don't look like the real world."
They hope this data will encourage textbook publishers and educators to add more diverse images, ensuring that future eye doctors are prepared to see everyone, not just the people in the "red car" photos.
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