Is there research into children who are tube fed longer term, e.g. at age 11, and is this physiological or behavioural?

At the present time, research was at the stage of looking at patient surveys and considering anecdotal evidence as to what works. For some families the introduction of a blended diet through the peg tube seems to have been effective but there was no hard and fast rule and it was very difficult. It seemed certain that feeding and speech difficulties were closely related and to get anywhere with research, it would require psychologists and speech and language therapist all working closely together.