Screening for glaucoma: the time taken by primary examiners to conduct visual field tests in practice.

A panel of 101 primary examiners (optometrists or their ancillary staff) in England and Wales prospectively recorded the time taken to examine the central visual fields of each of 10 (or more) of their patients. The results indicate that the time depended not only on the test procedure but on how frequently the examiner conducted such a test. A basic test with semi-automated field screening equipment, applied routinely by 30 examiners on 547 patients, took an average 3.7 min per patient; (lower quartile 2.8 min). For such examiners, a standard extended test took 4.9 min. Similar times applied whether tests were conducted by an optometrist or an assistant. It was concluded that visual field screening in a normal population could reasonably be assumed to take an average 4 min per patient.