Usability Study of Fingerprint and Palmvein Biometric Technologies at the ATM

The usability of four biometric ATM designs were assessed in comparison to an existing ATM. Participants (N=46) were observed using two biometric technologies (palmvein and fingerprint) at two positions (horizontal and vertical) on the ATM in a repeated measures design. Measures included a usability attitude questionnaire, a quality metric and data from interviews and observation. Usability scores for the ATMs with biometric sensors were comparable to scores for the existing ATM even though they added an extra step to the typical ATM process. No differences were found in usability scores between palmvein and fingerprint sensors on the ATMs, or for the different positions. The quality results were more emphatic with a definite preference for horizontal positioning of sensors on the ATM, which corresponded with observations and participant comments. The horizontally-mounted fingerprint sensor was rated significantly higher in comparison to the existing ATM. Participant preference also favoured the fingerprint sensor over the palmvein sensor. It is argued that the quality metric results picked up on issues of security, whereas the usability results did not. There was a clear divide in the rankings of the existing ATM with equal scores ranking it first and last. Nearly 20% of the participants said they would not register to use biometric technologies. It is not clear how much of this is due to usability issues or underlying negative attitudes towards biometrics. Observations and comments from the participants point to the importance of improving user feedback in future designs.