Bowlby believed that attachment was innate / biological / an evolutionary drive to help us to survive
Grossman
German parents seek ' independent , non clingy infants who do not make demands on parents , but obey their commands '
Indigenous Researchers
Researchers who are from the same cultural backgrounds of the participants who are being studied
By using indigenous researchers you can avoid researcher misunderstanding of language used by participants or the researchers having difficulty giving instructions
Indigenous Researchers also help to avoid bias due to stereotypes and potential prejudice about another culture which could impact results
Indigenous researchers add validity due to successful communication has a higher chance of existing meaning there is higher internal validity as you are more likely to test what you intend to test
However due to the indigenous researchers existing and Van Ijzendoorn and Kroonenburg not being there for the individual studies there is a colossal lack of control