The Goldmann applanation tonometer, among clinical instruments presently available, may provide the most valid estimate of intraocular pressure in humans. Examination with this tonometer offers a promising method of collecting descriptive data on the frequency distribution of intraocular pressure. Accordingly, it is important to compare the field performance of Goldmann applanation tonometry with Schiotz indentation tonometry, since the Schiotz instrument has been used in most population studies. Such a comparison might also provide information of clinical interest.
Since changes in posture are known to influence the level of ocular pressure,1,2 a comparison of the Goldmann tonometer with the Schiotz tonometer should be made on subjects remaining in the same position. The Schiotz instrument performs properly only when oriented vertically, and accordingly, the supine-recumbent posture is an appropriate common position for a comparative study. One comparison of these instruments has been reported1 in which both examinations were performed in
SCHWARTZ JT, DELL'OSSO GG. Comparison of Goldmann and Schiotz Tonometry in a Community. Arch Ophthalmol. 1966;75(6):788-795. doi:10.1001/archopht.1966.00970050790015