Kety - Adoption study Flashcards
Aim
To see if there is a genetic basis for schizophrenia using an adoption study method
What was the sample of the study?
34 Adoptees with Schizophrenia and 33 controls (and all their families)
What were the adoptees and the control group matched on?
Age, gender, age of adoption and Social class of adoptive family
Where is the sample from?
Denmark
How did we check the ‘Schizophrenia’ for them and their family members
Review medical records
How many family members were looked at?
465
How were they all assessed as having ‘schizophrenia spectrum disorder’ or not?
4 Psychiatrists completing a blind diagnosis on the medical records
What was a finding about the Schizophrenic patients families?
The research found more signs of schizophrenic spectrum disorders in the index participants’ biological family than their adoptive family
What was a finding between the Schizophrenia and control groups families?
They also found more spectrum disorders in the index participants’ biological families than in the Controls’ biological families. 8.7% Vs 19%
What is a weakness of the sample of Kety?
It is ethnocentric as all the participants are from Denmark so it isn’t representative of a wider population
Are the results from this study reliable?
Kety tried to replicate this study at various points and the procedure could be repeated and found similar results
Is the procedure standardised/reliable?
Yes- the procedure of accessing medical records and having psychiatrists review them can be easily replicated
What can we say about inter-rater reliablity in Kety?
The study is high in inter-rater reliability because there were 4 psychistrists agreeing on the diagnosis
What is a problem with schizophrenia spectrum disorders?
It is not a clinical diagnosis as it involves various ‘levels’ of uncertainty so it might be subjective/invalid as a measure of Schizophrenia
What is a problem with adoption studies which is true of Kety?
There are shared environmental factors between the adoptee and their shared environment so we cannot separate nature from nurture fully
