An increasing number of parents request delayed start for Kindergarten. The belief is this will give them a “boost” over their classmates. The research I have found does not suggest this, does your research have any further information?

Yes, a vexed question. Kay Margetts (2008) here at University of Melbourne did a study and found that within a year or two it was not possible to track back kids who started earlier or were red shirted. There is evidence that older kids in a class have an advantage but there are so many factors that it is hard to find any evidence of impact re starting dates. A lot relates to the policy – in New Zealand for example the child starts school in the semester they turn 5 (until recently it was on the day they turned 5), whereas in Australia it is in the year they turn 5 -- In Australia but not New Zealand there is a higher correlation between starting age and performance in the early years (hence star signs are a good proxy!!!) but not so high in New Zealand – so lot depends on the local policy. My own reading would say deliberately holding back for some form of advantage is hard to defend and too big a gamble – most parents who worry about this matter should have a good sense of the right time --Again here in Australia some starts are lowering the entry age (Tasmania to 3) partly to avoid these games, but more to ensure a great start – as for some it is too late at 5 or 6! It is a pity that parents have this dilemma largely caused by poor policy (wide months for starting dates)” (John Hattie, personal communication, August 28, 2018).