Is there any evidence that alternative keyboard layouts prevent injury?

Question

When people proselytize DVORAK or COLEMAK and I ask them whether it actually prevents RSI, they usually point to metrics such as the following:

Your fingers on QWERTY move 2.2x more than on Colemak. QWERTY has 16x more same hand row jumping than Colemak. There are 35x more words you can type using only the home row on Colemak

(https://colemak.com/)

Sure. But that is pretty implicit, even if it were true. The assumption seems to be that less finger-moving is better. I'm not so sure.

I can't find any real evidence on the contrary either, though. So has it been proven more than anecdotally that using an alternative keyboard layout reduces wrist injury?

Answer 1

The problem with trying to set up a scientific study of RSI factors is twofold. First, RSI usually takes years before onset, so it's not a good fit for most controlled trials that need results in weeks or months. Second, they can't really do tests on people where the expected outcome for some of the subjects is injury. As a result, they rely on anecdotal and self reported evidence, but then compile and configure it such that it approximates a large group study.

Based on the repetitive nature of RSI, anything that can reduce the length of motion, number of moves, or effort involved has the ability to reduce the chance of injury. As you quoted from the Colemak site, they can do simulations from standard typing loads and show less flex, less travel, etc, which equates to less of the damaging repetition. But proving that this amount of change is sufficient to prevent injury, or that it is more effective than just getting a curved or tilted ergonomic keyboard, is difficult. Unfortunately, there's also not enough money in it to justify large studies, especially when they can already show verifiable finger travel data like you quoted.

Anecdotally, I switched to Dvorak in college on the promise of increased speed, which I found to be true (went from ~50 wpm on Qwerty to ~90 wpm on Dvorak in a few months of practice). Six years later, when I was forced by a job to switch back to Qwerty for a year or so, I noticed a marked difference in the fatigue in my hands at the end of the day.

Answer 2

I'm writing my own experience +research.

A Definition: A repetitive strain injury (RSI) is an injury to the musculoskeletal and nervous systems that may be caused by repetitive tasks, forceful exertions, vibrations, mechanical compression, or sustained or awkward positions. Here is the source.

There are several causes for an injury, like carpal tunnel syndrome, in jobs that involve repetitive wrist movement.

Some of the most frequent conditions are:

• diabetes
• thyroid dysfunction
• fluid retention from pregnancy or menopause
• high blood pressure
• autoimmune disorders such as rheumatoid arthritis
• fractures or trauma to the wrist

Here is the source.

It is also mentioned that Carpal tunnel syndrome can be made worse if the wrist is overextended repeatedly. Repeated motion of your wrist contribute to swelling and compression of the median nerve. @same source

I had Mild Carpal tunnel syndrome on both hands around 8 years ago.

I have visited a physiotherapist and advised to use rigid wrist braces and also learnt to keep my forearm-wrist-fingers straight. Here are some guides: And

This is why there are many ergonomic keyboards, mouses and mouse pads: and

I would definitely recommend a mouse pad that supports your wrist and forearm together. Some times when there isn't a proper pad, I put one of my thin books under my forearm!

So back to your question:

Is there any evidence that alternative keyboard layouts prevent injury?

As said in the Definition you are trying to reduce repetitive tasks by changing the keyboard layout. But... what about the sustained or awkward positions?

There are several causes for this types of injury. Using a keyboard layout like Colemak that wants to "make typing easier by placing the most frequent letters under the strongest fingers" could be interesting, but 20% reduction of finger movements, (in theory), could have an impact, how much? 5% or 10% or more?. No one can tell that.