Gottesman and Shields describe Flashcards
Date of the study?
1966
What type of study did this involve?
Twin studies.
What to twin studies look at?
Twin studies look at the concordance rate (degree of similarity) of twins with respect to the disorder being considered.
What was the aim of the study?
To investigate if there was any relationship between genetic make-up and the development of schizophrenia, by looking at the concordance rate for schizophrenia in groups of twins.
How did they gather the sample?
he researchers accessed records from Maudsley and Bethlem Royal Joint Hospital, which was a short stay psychiatric hospital with a large outpatients department.
What was the resulting sample?
57 twin pairs.
What other information on the twins was gathered in addiction to the hospital diagnosis?
The following information was obtained: hospital notes, case histories for the twins, personality testing, testing to examine thought disorders and tape recordings of 30 minute samples of verbal behaviour gathered by semi-structured interviews
(RESULTS) What was the concordance rate in the monozygotic twins?
In the monozygotic twins the concordance rate was 42% (i.e. 42% were both diagnosed as having schizophrenia)
(RESULTS) What was the concordance rate in the di-zygotic twins?
In the di-zygotic twins the concordance rate was 9% (i.e. 9% were both diagnosed as having schizophrenia)
What was the conclusion?
The researchers concluded that genes do appear to play an important role in schizophrenia because the concordance rate is higher in MZ twins than DZ twins. However environmental factors must also be important.
What did the researcher believe the best explanation for the findings was?
The diathesis-stress model which argues that schizophrenia is caused in part from a genetic predisposition and in part from environmental triggers. Gottesman and Shields thought that particular genes predispose someone to schizophrenia by lowering the threshold for coping with stress.
