Likert Versus Visual Analogue Scales in Ecological Momentary Assessment: Initial Evidence That Likert Scales Come With Reduced Capacity to Sustain Attentiveness

Ecological momentary assessment (EMA) prompts participants to report on various variables such as their current emotions, cognitions, or behaviors multiple times per day across several days, enabling the collection of rich, high-frequency data. However, the high frequency of measurements can burden participants, potentially leading to non-compliance or inattentive responding that compromises data quality. To minimize these effects, it is crucial to understand how EMA design factors influence inattentive responding and, consequently, the quality of the collected data. This study contributes to this aim by investigating how response format, as a more subtle design choice, affects inattentive responding in EMA. We re-analyzed data from two experimental EMA studies, in which surveys were administered either in a Likert-type or a visual analogue scale (VAS) format in between-subjects designs. Each dataset was analyzed with one of two state-of-the-art confirmatory mixture modeling approaches to examine whether response format is associated with differences in (a) the overall level of inattentive responding and (b) its associations with two fatigue- and attention-related contextual factors: the cumulative number of EMA study days and time of day. Across datasets and analytical approaches, we found indications that Likert scales yield up to 3 percentage points higher rates of inattentive responding than VASs, though the temporal patterns varied across studies. In Study I, differences were observed in overall inattentiveness levels, with parallel increases across EMA days. In Study II, initial inattentiveness was comparable between formats, but the Likert format showed a steeper increase over time. Implications for EMA design are discussed.