From Open Text to Tick Boxes: Question Format Effects on Public Support for Carbon Capture and Storage

Public attitudes towards emerging, technically complex climate technologies are difficult to measure with standard closed-ended survey items. When issues are low in salience, closed formats may elicit satisficing and pseudo-opinions, thereby masking ambivalence. We examine these dynamics for carbon capture and storage (CCS) using a probability-based online survey(n = 3,068). Respondents first read a brief information text and provided open-ended written responses. They then answered a closed-ended forced-choice question on their stance toward CCS.

We show that the question format fundamentally influences measured public attitudes toward CCS. “No opinion” was selected by 23% in the closed-ended item but was coded in only 4% of the open-ended answers, while item nonresponse was higher for the open-ended question (14% vs. 0.4%). Within-person comparisons show that respondents who expressed conditional support or uncertainty in open text responses often chose “positive” when constrained by predefined categories. Open-ended elaboration is socially patterned, indicating that each format carries distinct biases.

These findings highlight a measurement trade-off: closed-ended items maximize efficiency and response rates but can overstate support and underestimate complexity, whereas open-ended items reveal ambivalence yet impose greater respondent burden.