Bowlby’s continuity hypothesis is supported by Hazen and Shaver’s ‘Love quiz’. Whereby they asked participants to write in to their local newspaper which consisted of two parts – a childhood attachment type measure containing a list of adjectives to describe their relationship with their parents and a questionnaire to assess their feelings about love. For example does true love exist? Does love last forever? Hazen and Shaver analysed data of the first 620 responses, with participants ranging from 14 to 82 years old. They found a significant correlation between childhood attachment type and later adult relationships styles. Concluding there was evidence to support the continuity hypothesis, but some strayed from this, and went on to form stable relationships in their later life. This study can be praised for its large sample, its high in population validity the implication being that we can more easily generalise the findings to the wider population. However, the study used a volunteer sample, therefore may be subject to a volunteer bias; as a certain type of person is likely to volunteer for a study, someone who has increased time and motivation on their hands. Moreover, the participants had to self report their early attachments and later relationships, the implication being that there is a risk of social desirability bias with participants wanting to be viewed in the best possible light. Also the retrospective aspect of the questions can be criticised for its reliance on memory, memory can be unreliable and inaccurate. Therefore, it can be argued this study provides a weak support base for Bowlby’s idea of continuity, however, its praises outweigh its weaknesses and many view it as a valuable piece of research.
Bowlby’s argument that attachments must take place in a critical period is undermined by Rutter’s study of Romanian orphans. Those who were adopted before they were 6 months old went on to form normal stable relations with their new families, supporting continuity. But those who were adopted after they were 6 months old went on to form normal stable relations with their new families also, they just encountered more difficulties and often it took longer. Therefore an argument has been put forward that attachment has a sensitive period as opposed to a critical period in which an attachment must be formed.
Overall there is much research to support Bowlby’s theory of attachment and it is viewed positively in the field of psychology. It has had important real life applications with regards day care practices and for hospitals in terms of the amount of time mothers spend with their babies after the child is born.