When survey respondents' answers include pauses, stammers, and hedges, does this indicate that they are in danger of misinterpreting the survey question? Or are disfluencies so common in ordinary discourse that they are nondiagnostic? We analyzed respondents' first utterances after survey questions in a corpus of 42 laboratory-based telephone interviews (Schober & Conrad, 1997). Because respondents had answered questions on the basis of fictional scenarios, it was clear when their answers reflected a need for clarification. Half the respondents participated in strictly standardized interviews in which any clarification was prohibited, and half participated in more collaborative interviews in which clarification was encouraged. Results showed that respondents were more likely to pause longer, produce an um or uh, repair their utterance, and describe their circumstances in the first turn after a question was asked when answering about scenarios for which they needed clarification. Various combinations of discourse cues were also diagnostic of the need for clarification, although often only in the strictly standardized interviews.