The systems can be used to draft reports, letters, memos, and emails. These systems need to be trained to recognize the user's voice. Instead of reading from a word list, as was the case for discrete programs, Dragon NaturallySpeaking requires users to spend 20-30 minutes reading passages from a novel. ViaVoice requires the user to spend only a few minutes reading several sentences. Both programs allow the user to do more training at a later time and train the system to recognize specific words.
Further training increases the recognition accuracy.
Both systems are designed for adult voices. They also claim that it can learn dialects, accents, and individual pronunciations quickly and automatically, although an independent reviewer demonstrated significant errors when speaking with a heavy accent. IBM advertises tests claiming recognition using an evenly modulated, moderately paced voice was about 80 to 90 percent after minimal training and grew to greater than 95 percent after more intense training exercises. Use of unfamiliar words, such as names or slang, decreases ViaVoice's accuracy only until the program incorporates them into its vocabulary. If such claims prove to be accurate, these programs should be effective and useful for people with writing problems.