Evaluation of Lang’s Test as a Screening Procedure in Children

Abstract

Screening procedures in preschool children have been done with increasing frequence in many countries. Methods vary much and the single most used way of predicting any eye problem has been the visual acuity (VA) measurement (FRIENDLY, 1978; HATFIELD, 1967; INGRAM et al. 1986). Many tests have been used,specially Snellen’s “E” and also the Sheridan-Gardiner (LIPPMANN, 1974; SHERIDAN,1976). Some authors proposed different ways of screening, including a quick eye examination, either by technicians specially trained or by physicians not necessarily ophthalmologists (HATFIELD, 1967; FRANKENBURG et al., 1973). A screening procedure has to be easily done by non-medical personnel to be widely used. We should instead not include eye examination, such as cover test and eye reflex observation, by any other than the ophthalmologist as to avoid many errors that could than occur. More recently some authors (HAMMOND & SCHMIDT, 1986; REINECKE & SIMONS, 1974) have been enthusiastical about new stereotests based on random dot principles and suggest that one of them should be used as the only test to screen preschool children (HAMMOND & SCHMIDT, 1986). Lang (1983) described his stereotest which is the only one that does not require the use of special glasses in order to assess stereoscopic vision (SV) and is also based on random dot principles.