Adoption Study Flashcards
What is the study
Kety et al (1963)
What was the aim of the study
To find out if there is a genetic cause for schizophrenia, the researcher compares rhe adoptive family and the biological family of schizophrenia sufferers to see if there is a higher rate if schizophrenia related illnesses among biological relatives than adoptive relatives
What was the sample
463 relatives
Ages 20 - 43
All from Denmark
Mostly white and not much immigration
All adopted
Men and women
Procedure - how the sample was found
Used danish family records to track down 463 relatives and used mental, health register to asses their mental status
All were adopted (separating out environmental influence)
Index group had schizophrenia and control group had no mental disorder
Matched on age gender and when they were adopted
Procedure
4 danish psychiatrists used the medical records to diagnose fa ily members using a blind test so didn’t know whether were adopted or biological
Once diagnosis made identities were revealed and were assigned to adoptive family groups (IA and CA) or biological family groups (IB and CB)
In four cases couldn’t reach conclusion as were sometimes unsure about diagnosis so these were dropped from the study
What were the categories family members were sorted into
B1 to B3 index participants
D1 - uncertain chronic schizophrenia
D2 - uncertain acute schizophrenia
D3 - uncertain borderline schizophrenia
C - schizoid or inadequate personality
Results
Researches found more signs of schizophrenia spectrum disorders in index participants biological family than adoptive family and more spectrum disorders in index participants biological family than controls biological
IB % with schizophrenia spectrum disorders 8.7 %
CB % with schizophrenia spectrum disorders 1.9%
Conclusion
There seems to be a genetic component to schizophrenia as schizophrenia adoptees in their biological families were more likely to have schizophrenia than the families of controls
Reliability
Used medical records and was a blind procedure so removes unwanted bias
Replicable
It was replicated in 1975, 1978 and 1994 adding interviews and similar findings were found giving test retest reliability
Psychiatrists were used and 4 of them giving inter rater reliability
But diagnostic categories were vague and depended on subjective interpretation
Application
Applications for families with history of schizophrenia looking to adopt a child
Also can help a child who has a genetic predisposition to avoid factors that may make it worse
Can guide them away from dugs and stressful careers and look for early symptoms, less destructive if diagnosed earlier
Validity
Gives American danish study concurrent validity and construct validity
Vague and unclear concepts in research makes it sound like anything could fall into it as anything could be seen as schizophrenia - Jane Joseph
Ethics
Participant weren’t directly approached only data was analysed, done under danish laws where consent isn’t needed
Legal but could be seen as unethical
Could lead to stress in families with a history of mental illness
