๐ฑ. ๐๐๐ก๐๐ฅ๐๐๐๐ฆ๐๐๐๐๐๐ง๐ฌ:
The large sample size in the study should help with the generalisability of Schaffer and Emerson's stages.
However, the sample characteristics may make the sample less generalisable to other populations. This is because child-rearing practices vary so much between social groups/cultures.
So, patterns of attachment development in 1960s Glasgow may be quite different from that in, say, present-day Southampton or Liverpool.
Therefore, we cannot assume the same stage pattern would apply universally.