Good application to everyday life - provides information on the effects on children's development that can help us to ensure children are getting the best from their everyday life (eg. the way nurserys, schools are run)
Gives a general understanding of the way in which humans develop and attempts to provide information for questions that have been debated for years eg. nature/nurture debate
The Developmental Approach takes a 'lifespan' approach to pyschology, and in many cases produces a lot of both quantative and quantitative data because of the detail needed to make conclusions on the subject. This leads to in depth results and valid conclusions.
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The developmental approach has many applications to everyday life and it provides information on the effects of day care on children's development. This can help with childhood problems and issues. The understanding we gain from this helps us to provide children with what should assist their healthy and happy psychological development and to avoid things which may have a negative impact on it.