 A survey in 2005 of 88 paediatric neurologists in the US found that 36 % regularly prescribed the diet after three or more drugs had failed ; 24 % occasionally prescribed the diet as a last resort ; 24 % had only prescribed the diet in a few rare cases ; and 16 % had never prescribed the diet . There are several possible explanations for this gap between evidence and clinical practice . One major factor may be the lack of adequately trained dietitians , who are needed to administer a ketogenic diet programme . 
