Evidence Against Dvorak
Naturally, these false results were going to get found out. As many businesses and government agencies contemplated changing keyboards in the mid 1950s, the General Services Administration commissioned Strong's study to confirm the earlier results. This study provides the most compelling evidence against the Dvorak keyboard. It was a carefully controlled experiment designed to examine the costs and benefits of switching to Dvorak. It unreservedly concluded that retraining typists on Dvorak was inferior to retraining on QWERTY.
In the first phase of the experiment, 10 government typists were retrained on the Dvorak keyboard. It took well over 25 days of four-hour-a-day training for these typists to catch up to their old QWERTY speeds. (Compare this to the Navy study's results.) When the typists had finally caught up to their old speeds, the second phase of the experiment began. The newly trained Dvorak typists continued training and a group of 10 QWERTY typists (matched in skill to the Dvorak typists) began a parallel program to improve their skills. In this second phase the Dvorak typists progressed less quickly with further Dvorak training than did QWERTY typists training on QWERTY keyboards. Thus Strong concluded that Dvorak training would never be able to amortize its costs. He recommended instead that the government provide further training in the QWERTY keyboard for QWERTY typists.
The GSA study attempted to control carefully for the abilities and treatments of the two groups. The study design directly paralleled the decision that a real firm or a real government agency might face: Is it worthwhile to retrain its present typists? If Strong's study is correct, it is not efficient for current typists to switch to Dvorak. The study also implied that the eventual typing speed would be greater with QWERTY than with Dvorak, although this conclusion was not emphasized.
Much of the other evidence that has been used to support Dvorak's superiority actually can be used to make a case against Dvorak. We have the 1953 Australian Post Office study already mentioned, which needed to remove psychological impediments to superior performance. A 1973 study based on six typists at Western Electric found that after 104 hours of training on Dvorak, typists were 2.6 percent faster than they had been on QWERTY. Similarly, a 1978 study at Oregon State University indicated that after 100 hours of training, typists were up to 97.6 percent of their old QWERTY speed. Both of these retraining times are similar to those reported by Strong but not to those in the Navy study. But unlike Strong's study neither of these studies included parallel retraining on QWERTY keyboards. As Strong points out, even experienced QWERTY typists increase their speed on QWERTY if they are given additional training.
