Does a warning help children to more accurately remember an event, to resist misleading questions, and to identify unanswerable questions?

This study examined potential effects of a warning instruction prior to an eyewitness interview including answerable and unanswerable questions, which both were either unbiased or misleading. A total of 84 six-, eight- and ten-year-old children were shown a short video about the production of sugar and they were individually questioned about it one week later. Half of the children received the warning instruction. The results revealed clear age effects in the correct answers and accuracy to answerable questions and in the appropriate "don't know" answers to unanswerable questions, but no effect of warning across all dependent measures. These findings suggest that preschool and elementary school age children cannot use such information adequately to increase their number of correct answers in the interview. Results are discussed in terms of cognitive explanations for these deficits.