Key research - Gottesman

• Aim

  To investigate in a large sample the probability of a child being diagnosed with a mental disorder if either or both of the parents had this disorder
• Sample

  Anyone in Denmark aged between 10 years and 52 years in January 2007 and with a clear link to their biological parents. This meant a sample of almost 2.7 million people and their parents being studied
• Procedure

  Using data from the Psychiatric Central Register, Gottesman et al identified four groups of people:

  • Both parents were admitted to a psychiatric hospital with diagnoses of schizophrenia, bipolar disorder or depression
  • ON parent was admitted to a psychiatric hospital with a diagnosis of schizophrenia or depression
  • Neither parent admitted with a diagnosis of a disorder
  • The 'general public' (with no data available on whether they had parents admitted with psychiatric illnesses or not)
• Findings

  • Both parents admitted with the disorder - schizophrenia = 27.3% - bipolar = 24.9%
  • Neither parent admitted with the disorder - schizophrenia = 7% - bipolar = 4.4%
• Other important to emerge were as follows:

  • There seemed to be some 'genetic overlap' between schizophrenia and bipolar disorder (if both parents had schizophrenia, then 10.8% of children having bipolar disorder)
  • If both parents had been admitted to a psychiatric hospital, then there was an increase in the likelihood of being admitted with any disorder (if both parents had bipolar disorder 44.2% of people were admitted)
  • At age 52, very few people were receiving a fresh diagnosis of schizophrenia; however, at the same age, fresh diagnoses of bipolar disorder were still being made
• Conclusions

  • Where both parents have been admitted to a psychiatric hospital or bipolar disorder, their offspring are at 'super-high risk' of being admitted with a disorder themselves
• Nature/nurture evaluation

  • The findings support the view that genetics does play a major role in your likelihood of developing a mental disorder (specifically depression or schizophrenia) at some point in your life
  • Findings don't take account of the possibility that living with a parent with mental disorders may cause you to learn certain behaviours or may be fairly stressful which could predispose people to develop mental health issues#
• Freewill/determinism evaluation

  • Deterministic in that it suggests that if your parents suffer from depression or schizophrenia you are much more likely to later in life as well
  • Very little room for free will in this explanation and does not take account of lifestlye choices etc. (although people are unlikely to choose to develop a mental disorder)
• Sampling bias - evaluation

  • Very large sample of people used in the study which means that the study should be fairly representative
  • The range of ages studied could be considered a strength but as some were only 10 at the time of the study, we don't know how likely they would be to develop mental illness later in life
  • People with bipolar and depression are more likely to be treated as outpatients rather than be admitted to hospital so this may skew the data
• Ethnocentrism - evaluation

  • Denmark may not be representative of the likelihood of developing depression or schizophrenia in other countries or cultures (may be less diverse than other countries)
  • Use of ICD to diagnose mental illness which might lead to different rates of diagnosis if other systems were used e.g. DSM
  • In Denmark, healthcare is provided freely to service users and funded by the public which could result in differences in rates of diagnosis or how often they are admitted to hospital compared to other countries where they have to pay directly for healthcare