Decision Delay

The time a user spends deciding whether to accept or reject a suggestion from a predictive system, such as a word prediction list on an assistive technology device or keyboard. Decision delay is a cognitive cost that can offset the motor efficiency gains of word prediction: while fewer keystrokes are needed when a prediction is accepted, the time spent visually scanning the prediction list, evaluating options, and making a selection decision may slow overall text generation. Research has shown that decision delay is a significant factor in why word prediction does not always improve text entry speed despite reducing keystroke count, particularly for users who can type at moderate speeds without prediction assistance.