After studying 1,128 office patients and 1,500 school children, Glorig and House1 concluded that in almost all cases the hearing loss at 4,000 cycles was as great as, or greater than, the loss at any lower frequency. They recommended, therefore, that testing at 4,000 cycles be used as a screening test in schools, industry, the military forces, and doctors' offices.
In a subsequent article,2 the same authors called attention to the fact that many persons show a slight hearing loss at 4,000 cycles, something which is relatively unimportant unless accompanied by losses at the lower frequencies. They recommended, therefore, that 2,000 cycles be added in school screening programs to avoid needless referrals. That is, any child who failed to hear 15 db. at 4,000 cycles was to be tested at 2,000 cycles, and if this tone were heard at 15 db. no further testing was necessary at that