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The accuracy of reading speed measurement by stopwatch versus measurement with an automated computer program
Wolfgang Radner1, Gabriela Diendorfer2, Bettina Kainrath3
1Austrian Academy of Opthalmology, Vienna, Austria.
Purpose:
To compare the reading time and reading speed measurements obtained with a stopwatch with those of an automated computer program for measuring reading speed and acuity (rad-rd© ; patent: AT 504635B1/10-2006).
Methods:
The rad-rd© was used (in conjunction with a PC and microphone) for the computer-based measurements. In rotation, each of four examiners took a turn reading the 12 sentences from one of the four RADNER Reading Charts to three other examiners, who served as stoppers. The stoppers simultaneously measured the reading time with a stopwatch while a fifth investigator used the rad-rd© to obtain computerized measurements. The stopwatch measurements were then statistically compared with the rad-rd© measurements.
Results:
The mean reading time obtained with the stopwatch measurements was 4.34 ± 0.57 seconds (196.21 ± 21.79 wpm), versus 4.44 ± 0.59 seconds (192.24 ± 22.20 wpm) by computer measurement (r = 0.84). Of the 144 stopwatch measurements, 97 (67.36%) were shorter, and 47 (32.64%) were equal to (n = 5) or longer than the computer measurements. The mean difference for the shorter measurements was -0.17 ± 0.1 seconds (3.91% of the mean reading time), and the mean difference for the longer measurements was 0.11 ± 0.1 seconds (2.53% of the mean reading time). Most differences ranged from -0.1 to 0.1 seconds (42.36%). The results did not differ significantly among the four stoppers.
Conclusion:
The rad-rd© is an accurate, automated computer program for measuring reading time. Stopwatch measurements, although subject to inaccuracy from several sources, remain a reliable and simple method for analysis of reading performance.
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