Purpose. In police interviews children may be asked the same question many times. We investigated how the number of repetitions and the interval between those repetitions affected the accuracy and consistency of children's responses.
Methods. 156 children aged 4–9 years watched a staged event and were interviewed individually 1 week later. Children were asked eight open-ended questions, which were each repeated a further four times (making a total of forty questions). Half these open-ended questions could be answered from information in the event, and half were unanswerable (so children should have said ‘don't know’ in response to these questions). The questions were repeated in gist form. The interval between an initial question and its repetitions was varied by use of other questions and twenty non-repeated filler questions. The intervals between repetitions were immediate repetition, repetition after a delay of three intervening questions, after a delay of six intervening questions, and after ten or more intervening questions.
Results. Over a quarter of children's responses to repeated questions changed, usually resulting in a decline in accuracy, particularly after the first repetition. Subsequently, the number of repetitions and delay interval had little effect on responses to answerable questions although accuracy to unanswerable questions continued to decline.
Conclusions. Question repetition had a negative affect on children's consistency and accuracy. For unanswerable questions in particular, the more often a question was repeated the more likely children were to invent a response.