In this study, we investigated whether incorporating eye tracking into cognitive interviewing is effective when pretesting survey questions. In the control condition, a cognitive interview was conducted using a standardized interview protocol that included pre-defined probing questions for about one-quarter of the questions in a 52-item questionnaire. In the experimental condition, participants' eye movements were tracked while they completed an online version of the questionnaire. Simultaneously, their reading patterns were monitored for evidence of response problems. Afterward, a cognitive interview was conducted using an interview protocol identical to that in the control condition. We compared both approaches with regard to the number and types of problems they detected. We found support for our hypothesis that cognitive interviewing and eye tracking complement each other effectively. As expected, the hybrid method was more productive in identifying both questionnaire problems and problematic questions than applying cognitive interviewing alone.