Gamification has been proposed as a possible solution to low user engagement in open collaboration communities. However, most studies do not present statistical analyses and few studies analyze the criterion validity between behavioral and self-reported engagement measures. This study seeks to understand whether gamification contributed to greater behavioral and self-reported engagement in an open collaboration community. We conducted an online field experiment to analyze user engagement in two versions of a new feature, with or without a game design element (Progress bar), with 36 and 37 users, respectively. A subset of the participants (18 users) answered an online questionnaire about their engagement with the system. We found that the group of users with the highest self-reported engagement scores performed the most actions, and users who accessed the Progress bar performed the highest number of actions. More studies are needed to better understand the relationship between each action and the engagement.