Complete a two page paper (not including the cover and reference pages) that summarizes the research article.

Please include these points that when discussing the review:

a. Explain the research question (what are the researchers hoping to answer).
b. Describe the study (where did they get their sample, how did they conduct the research)
c. Describe the research findings.
d. Do you have confidence in the researchers’ findings (i.e., were there critical flaws in the study design, questions of confounds that might have occurred in the study)?
e. Does the study generalize to other people that were not the subject of the research (e.g., college student study generalizing to everyone, study in the US applying to other cultures)?
f. What does the study mean in the big picture and how does it apply to society in general (i.e., how does it impact society in general)?
g. How does the study explain the role of genetics in humans



Article review: Schizophrenia






This is a study that was conducted by; Mortensen P. B., Pedersen C.B., Westergaard T., Wohlfahrt J., Ewald H., Mors O., Andersen P.K., and Melbey M. They carried out their study in Denmark with the Danish population as their study subject.

The study aimed at finding the relationship between genetics and environmental factors in the risk of schizophrenia. Most researches in the past had identified the biological factor of genetics and environmental factors such as obstetrical complications as crucial factors in the risk of schizophrenia. However, no single study had been carried out to find out about the relationship between biological and environmental factors in the risk of schizophrenia. These researchers meant to answer the question about the role of both environmental and genetic risk factors and their interaction in mental disorders. This is a question had had so far not been given any attention. They set out to discover the interplay between family history, place and season of birth in relation to risk of schizophrenia.

This study was conducted in Denmark after an approval by the Danish Scientific Ethics Committees. Population-based registries of Denmark were used in the study. The data used was sourced from the Civil Registration System in Denmark. A population co-hort of 1.75 million people was established. All their mothers were Danish, born between 1935 and 1978. From this, they linked with the Danish Psychiatric centre Register. 2669 cases of schizophrenia among cohorts and additional members were identified. This was the baseline for the study.

The study established that risk of schizophrenia was highest in persons with a father, mother, or sibling with the disorder.  The risk of schizophrenia was also associated with place of birth. The degree of urbanization of the place one was born or raised in affected the risk of schizophrenia. It was found out that people born in urban areas had a high risk of schizophrenia as compared to those in rural areas. The season of birth also played a role in the risk of schizophrenia. People born between February and March showed a high risk while those born between August and September showed a low risk. The total risk of schizophrenia in family history was 55.5 percent, urban birth risk was 34.6 percent, and 10.5 percent for the season of birth.

These findings can be banked on to some degree. This is because they used existing data to correlate the genetic factors with environmental factors. This is something other past researches had not taken into consideration as they concentrated on the prevalence only. However, this study should have incorporated other environmental factors apart from place and season of birth. By choosing to dwell on these two, it makes the study so narrow that it cannot account for all the other environmental factors.

The study was based in Denmark and employed data on the Danish population. However, the researchers in their conclusion have applied their findings to other populations. In doing this, they make us think that their findings should be accepted as a universal truth. This however is not right as environmental factors are not constant in all cultures. If they undertook to research similar cases in different societies, they could end up with contradicting findings.

This study was meant to prove that genetics is not the only factor playing an important role in the risk of schizophrenia. Environmental factors are the main influencers of genetic factors and so play the most role. This is true because most disorders have different causes that come into play. This study therefore paints a picture of how environmental factors correlate with genetic factors to cause schizophrenia. The society is therefore encouraged to be on the look-out for other factors influencing schizophrenia besides genetics.

This study still credits genetics as the major cause of most or all cases of schizophrenia. The family history is therefore an important trend that should be keenly studied in order to determine the probability of schizophrenia. However, genetics may be influenced by other external factors, mainly in the surrounding environment of a person. In the case of schizophrenia therefore, genetics are not sufficient according to this study as the place and season of birth also play a role.

This kind of study is unique as it has evaluated and quantified the contributions, and interactions between familial and non-familial risk factors in the risk of schizophrenia. Since it is among the first to study the relationship between familial and non-familial factors in the risk of schizophrenia, it should send more scholars back to the drawing board for more conclusive and compact findings.


















Effects of family history and place and season of birth on the risk of schizophrenia.

Mortensen, Preben Bo; Pedersen, Carsten Bøcker; Westergaard, Tine; Wohlfahrt, Jan; Ewald, Henrik; Mors, Ole; Andersen, Per Kragh; Melbye, Mads

The New England Journal of Medicine, Vol 340(8), Feb 1999, 603-608. Doi






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