David Flood, a US staff physician who spends 3 months every year working at the Maya Health Alliance in the remoter regions of Guatemala has found Isabel particularly useful when seeing very young children who have been referred to him with unusual developmental difficulties which have occurred as a result of the lack of any early screening programmes. “I use Isabel to refine my thinking” he says. David also uses Isabel regularly back in the US as a learning tool to help him improve his clinical reasoning skills.