Impact on the proportions of different attachment types in different countries
van IJzendoorn and Kroonenberg (1988) study
1. Looked at the proportions of secure, insecure-avoidant and insecure-resistant attachments across a range of countries
2. Looked at the differences within the same countries to get an idea of variations within a culture
Procedure
1. Researchers located 32 studies of attachment where the Strange Situation had been used to investigate the proportions of infants with different attachment types
2. 32 studies were conducted in eight countries, 15 in the USA
3. Overall the 32 studies yielded results for 1,990 children
4. Data for these 32 studies were meta-analysed, results being combined and weighted for sample size
In all countries secure attachment was the most common classification
The proportion of secure attachment varied from 75% in Britain to 50% in China
Insecure-resistant was overall the least common type, ranging from 3% in Britain to around 30% in Japan
Insecure-avoidant attachments were observed most commonly in Germany and least commonly in Japan
Variations between results of studies within the same country were actually 150% greater than those between countries
In the USA, one study found only 46% securely attached compared to one sample as high as 90%
