Another study which investigated privation is Hodges and Tizzard’s natural, longitudinal experiment. They studied 68 children who had all experienced privation due to bad institutional care. Over time, 24 of these children were adopted, 15 were restored to their previous homes, and the others stayed in the same institution. Hodges and Tizzard found that the children were adopted were able to form attachment, and those who were restored and stayed in same institution never formed attachment. Despite this, all children had difficulty forming peer relations.
In addition to this study, is a study done by Rutter. Rutter studied 111 Romanian children who all experienced one of the worst cases of institutional care ever recorded however, when the children that came to the UK and were adopted experienced reversal of the effects of privation such developmental dwarfism and insecure attachment if adopted early enough (usually before 6 months).
A strength of the Genie and Czech twins study is that they are both case studies. Because case studies involve using many different experimental and non experimental techniques, they collect a lot of detailed research and therefore, increase understanding of privation which can generate even more research and psychological breakthroughs and therefore, both studies are strengthened overall.
However, the fact both of the studies is case studies is a weakness as case studies often focus on one particular rare case. Because of this, studies cannot be repeated and therefore, lack reliability and may in fact be incorrect. Therefore, the case studies of Genie and Czech twins are weakened.
Also, the study of Genie in particular may lack validity. As previously mentioned, Genie apparently experienced mental retardation and this could possibly be a reason for her lack of speech and not privation. Because of this, the case study lacks internal validity as researchers may not be measuring what they intended to- the effects of privation and therefore, is weakened as a study to investigate privation.
A weakness of Hodges and Tizzard’s study is the fact it is longitudinal. This means it takes place over a large period of time and therefore, participants drop out. This therefore may lead to sample bias as there may be only a certain type of person in the sample and thus, is not representative. Because of this, the research done by Hodges and Tizzard cannot be generalised to the public and is weakened.
Also, Hodges and Tizzard’s as well as Rutter’s study are both natural experiments and thus means there is a lack of control of variables. This means that the adopted children may not have recovered the effects of privation because of adoption, but may be because they had friendly personalities, or were more socialable and thus, were able to form attachment easier. Because of this, the studies lack internal validity as they may not truly be investigating privation and are weakened.