Goldmann applanation tonometer calibration error checks: current practice in the UK

Assess current practice and views regarding checking Goldmann applanation tonometers for calibration errors in the United Kingdom.

Questionnaire survey.

A total of 100 ophthalmology residents from England, Wales, and Scotland attending the 2004 Congress of the Royal College of Ophthalmologists, UK, responded to a structured questionnaire. They were asked the following: how often they used different tonometers between clinical sessions; how often they checked their tonometers for errors; and who they felt was responsible for checking tonometers for calibration errors.

All respondents were using a different Goldmann tonometer for each clinic: 85% never check tonometers for errors; only 7% perform checks at the start of each clinical session; and 8% would only check the tonometer for calibration errors if they had suspicious or unexpected measurements. A total of 70% of respondents felt that calibration checks are not part of their responsibility. They believe that either nursing staff or other hospital staff should carry out calibration checks and ensure that tonometers are accurate. The remaining 30% felt that calibration checks should be carried out by the doctor using the tonometer.

Despite evidence that Goldmann tonometers lose accuracy during routine use in clinical practice, only a minority are checking the tonometers for calibration errors. There is no consensus as to who should be responsible for ensuring that tonometer calibration is maintained. We recommend that tonometers should be checked for calibration errors at least on a monthly basis by individuals identified by departmental protocols.