Use of General Case Instruction with Visually Impaired, Multiply Handicapped Adults in the Sorting of National Zip Codes

The purpose of the study was to determine whether the acquisition of independent sorting skills on a representative sample of the first two digits in national zip codes (zip code prefixes) results in generalized independent sorting of all 100 national zip code prefixes. It was found that two of the three visually impaired, mentally retarded subjects demonstrated improved generalized performance on probes of their nontrained ability to sort 100 national zip code prefixes during and following instruction on 9 representative prefixes.