Closed-captioned television presentation speed and vocabulary

This study summarizes an extensive research project on closed-captioned television. Caption data were recorded from 205 television programs. Both roll-up and pop-on captions were analyzed. In the first part of the study, captions were edited to remove commercials and then processed by computer to get caption speed data. Caption rates among program types varied considerably. The average caption speed for all programs was 141 words per minute, with program extremes of 74 and 231 words per minute. The second part of the study determined the amount of editing being done to program scripts. Ten-minute segments from two different shows in each of 13 program categories were analyzed by comparing the caption script to the program audio. The percentage of script edited out ranged from 0% (in instances of verbatim captioning) to 19%. In the third part of the study, commonly used words in captioning and their frequency of appearance were analyzed. All words from all the programs in the study were combined into one large computer file. This file, which contained 834,726 words, was sorted and found to contain 16,102 unique words.