DOES CONVERSATIONAL INTERVIEWING REDUCE SURVEY MEASUREMENT ERROR

Standardized survey interviewing is widely advocated in order to reduc e interviewer-related error, for example by Fowler and Mangione. But S uchman and Jordan argue that standardized wording may decrease respons e accuracy because it prevents the conversational flexibility that res pondents need in order to understand questions as survey designers int ended. We propose that the arguments for these competing positions-sta ndardized versus flexible interviewing approaches-may be correct under different circumstances, In particular. both standardized and flexibl e interviewing should produce high levels of accuracy when respondents have no doubts about how concepts in a question map onto their circum stances. However, flexible interviewing should produce higher response accuracy in cases where respondents are unsure about these mappings. We demonstrate this in a laboratory experiment in which professional t elephone interviewers, using either standardized or flexible interview ing techniques, asked respondents questions from three large governmen t surveys, Respondents answered on the basis of fictional descriptions so that we could measure response accuracy, The two interviewing tech niques led to virtually perfect accuracy when the concepts in the ques tions clearly mapped onto the fictional situations, When the mapping w as less clear, flexible interviewing increased accuracy by almost 60 p ercent. This was true whether flexible respondents had requested help from interviewers or interviewers had intervened without being asked f or help. But the improvement in accuracy came at a substantial cost-a large increase in interview duration. We propose that different circum stances may justify the use of either interviewing technique.