VAN IJZENDOORN AND KROONENBERG (1988) META-ANALYSIS:
The researchers looked at the proportions of secure, insecure-avoidant, and insecure-resistant attachments across a range of countries.
They also looked at the differences within the same countries to get an idea of variations within a culture.
They found 32 studies of attachment where the Strange Situation had been used. These were conducted in 8 countries, 15 in the US.
Overall the studies yielded results for 1990 children.
They data was meta-analysed, results being combined and weighted for sample size.