Verifying a ballot for correctness in an election is a critical task considering the large, negative repercussions of an incorrect ballot. Studies have shown weaknesses in the ballot review process in electronic voting systems, allowing up to 30% of the ballot to be changed without being noticed by 68% of voters (Everett, 2007). There is also a noted lack of research on the effect of navigation style on electronic voting system usability and review screen performance. In response to these issues, this study evaluated the usability and viability of alternative ballot verification and navigation methods in an electronic voting medium, specifically direct recording electronic (DRE) voting systems. Currently, most DRE’s employ an end-of-ballot review where all selections are confirmed at once at the end of the ballot, which has been proven to be ineffective. Several studies (Holmes and Kortum, 2013; Selker 2007) have also indicated that in-line confirmation, confirming each selection immediately after making it, and a combination of the two confirmation methods (Ghandi et al., 2005; Cohen et al., 1996) may prove to be a suitable alternatives.
The current study tested these methods of verification in terms of performance and usability to determine whether they are viable methods of verification as well as to provide a benchmark for review screen performance in a DRE. The method of navigation through the ballot, the ability to move backwards through the ballot or not after selecting a candidate, was also tested for its impact on usability and performance. The verification methods were evaluated on three metrics of usability as defined by ISO 9241 part 11; efficiency (time to complete a ballot), effectiveness (errors), and satisfaction (subjective usability). Participants cast their ballot in a mock national election using a custom DRE interface. Results indicate that in-line and dual confirmation methods prove to be viable alternatives for DRE review screens. In-line and dual confirmation perform similarly to end-of-ballot confirmation in terms of effectiveness, but differed in other usability and performance aspects, though not necessarily in a negative way. The most efficient method is end-of-ballot review, and dual confirmation produced the longest time spent on the review screen. End-of-ballot confirmation produced the highest satisfaction ratings, though survey results indicated that dual confirmation may be the most appropriate method in terms of voting. Based on the results from this study, further studies should be conducted to determine which confirmation method performs best as an error prevention tool.