Researchers have studied how to talk to children — for forensic interviews:
Forensic interviews are interviews where the goal is to get a child to tell you, truthfully, everything he or she saw or happened to them. Most of the time, it’s done when a child is the witness to a crime or the victim of one. For obvious reasons, these interviewers are always looking to minimize the chance that their questions will bias the answers children give, and are always trying to get children to do as much of the talking as possible.
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Open-ended questions are questions that can’t be answered by “yes” or “no” or a single word. In adult conversations, we use closed questions all the time without really knowing that they’re closed. For example, most adults hear “Is that your dog?” as an invitation to tell you all about their dog. Kids only see a yes/no question, and will stop talking after giving an answer.
What you want are open-ended invitations that get narrative answers from children. Invitations sound like like “Tell me everything about X” or “You said X. Tell me everything about that.” A 2007 study, looked at the interviews of 52 youths who were victims of sexual abuse. The details given by the children were more likely to be confirmed by another source when they were given in response to invitations.
Making sure the invitations are open ended is equally important. In a 1997 study, Sternberg et al. found that children 9 and older, produced around 50 details when given yes-no prompts and 140 details when narrative practice was used. Open-ended questions mean that children will tell you more. Yet another study not only found that “free-recall” (i.e. open-ended) questions produced the most response from children, but that closed-ended questions produced more details only as children get older.
When the children are older, they’ve learned not to take close-ended questions as literally as younger children do. They are closer to adults, who understand close-ended questions as invitations to tell a narrative. But for most children, close-ended questions will elicit the shortest answer possible. More than that, close-ended questions may even get a child to tell you things they know aren’t true. They feel pressured to answer close-ended questions.