We just got my ds5 tested on WPPSI-IV. We are puzzled by a subtest called cancellation. He got 37% in this subtest. His other related scores are high. bug search 17 (99%) , block design 19 (beyond 99%), overall fsiq is 144. I emailed the psychologist but did not get response yet. I know people on this board are very knowledgeable. I am wondering if some one could provide some insights or hypothesis that I should pay attention to. Thanks in advance.