We use multiple data quality screens prior to allowing a participant to take a study. The screens we use have been developed by us and have either been published in the peer-reviewed literature (Litman et al, 2015), or have been submitted for publication and are in the process of being reviewed.
There will always be some participants who are not attentive. Participants who provide questionable quality data will be replaced for free. Each participant will have a Participant ID automatically sent to your data file. Simply send us the IDs of participants whose data needs to be replaced and we will send new participants to your study in their stead.
Litman, L., Robinson, J., & Rosenzweig, C. (2015). The relationship between motivation, monetary compensation, and data quality among US-and India-based workers on Mechanical Turk. Behavior research methods, 47(2), 519-528.