In order to ensure the privacy of the study subjects, we
chose all of our observations spots in such a way that the
hands of the subject could be seen but the keypad itself
was not visible. Also, we positioned ourselves at a distance
where the ATM screen could not be read. Most importantly,
all observations are based on written data by the observer {
no surveillance technology of any kind was used, i.e., neither
videos nor photos were made.