The repeatability and validity of dynamic retinoscopy in assessing the accommodative response

Dynamic retinoscopy (DR) is an objective technique that has been used successfully to examine accommodative function of non-communicative patients. However, there are few studies examining its repeatability and validity. This paper addresses the repeatability and validity of a form of DR (a modified Nott technique), by comparing results to the Shin-Nippon SRW-5000 Autorefractor whose validity and repeatability have previously been demonstrated. Accommodative responses of 41 subjects (aged 6-43 years) were assessed using DR and the Shin-Nippon SRW-5000 Autorefractor. Three different target demands were used (10, 6 and 4 D). DR was shown to be repeatable for all target demands (paired t-test, p > 0.05). The results demonstrated good agreement between the autorefractor and DR. The results of the present study suggest that DR is a repeatable and valid objective technique for assessing accommodative function.