Effects of input methods on inter-key press intervals during continuous typing

Two popular input methods for Chinese typing, Microsoft New Phonetic and Boshiamy, were compared in terms of hand and finger loading, key-pressing speed and typing efficiency. Sixteen subjects typed an English and a Chinese text for 30 min each during two test sessions and all keystrokes and their inter-key press intervals were recorded by electronic activity monitoring software. Typing with Microsoft New Phonetic and with Boshiamy was found to have equal hand loadings, but typing with Microsoft New Phonetic was associated with a higher proportion of keystrokes at the number row. The subjects who used Boshiamy typed significantly more words per min than those who used Microsoft New Phonetic, though both groups had similar English typing speeds. The features of requiring fewer keystrokes to build a character and no need to choose matched words among homophones made Boshiamy a more efficient tool, but the risk of musculoskeletal disorders should be studied further. This study examined two input methods for typing Chinese and showed that typing with Boshiamy had a higher efficiency, including a higher proportion of key presses on the home row, required fewer key presses to build characters and resulted in a faster speed than with Microsoft New Phonetic. However, the potential risk of development of upper limb symptoms warrants further study.