It found that economies of scale were a key factor in the wide discrepancy, with smaller programmes spending more on each child, more on non-service costs and more on each key service than larger programmes.
An interim report on the cost-effectiveness of SSLPs said the disparities also did not appear to be based on differences in the level of existing services but 'seem to reflect different choices about which services to offer and at what level'.
The study, which is part of the national evaluation of Sure Start, found only 'very limited evidence' that programmes with higher levels of expenditure are reaching more children than those spending less.
For every additional 100 per child spent in the third operating year, deemed by the report to be when programmes became fully functional, only about 1 per cent more children were seen per month. The average expenditure per child is around 900.
Pamela Meadows, the principal author of the report and director of the cost-effectiveness module in the evaluation, said that while her research did not look at outcomes, the findings would bode well for the development of children's centres, which are 'drawing on a larger catchment area and wider range of children from within the same sort of budget as SSLPs'.
The report found that mainstream services, particularly in health and social services, were 'envious of the resources available to SSLPs compared with their own budgets'.
Hugh Thornberry, West Midlands director of the children's charity NCH, which works with 45 SSLPs nationally, said the evaluation was likely to continue to show variations between programmes as their shape had been determined locally, 'from the bottom up by talking to parents and communities'.
