Table 1: Statistic parameters for number of errors: entries in a wrong format and wrong date.

Version Wrong format Wrong date M (%) SD M (%) SD Version 1 (separate) 18.5 30.5 3.0 8.1 Version 2 (drop-down) 0 0 2.1 7.6 Version 3 (left) 22.3 33.5 1.6 5.6 Version 4 (inside, permanent) 22.3 32.8 1.7 5.7 Version 5 (inside) 25.7 32.5 1.9 7.5 Version 6 (calendar) 0 0 18.3 29.7