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An observational study aims to observe the effect of a risk factor, a treatment, or other intervention. The study's criteria needs to be specified in advance to find characteristics, behaviors, or specific events in the observations. Criteria, such as a list of things to look for, ensure consistency in the process of making observations.
It is crucial to acknowledge that other variables might affect a study. Suppose that a diet program's effect on a person's blood pressure is being investigated. It must be accounted for that there are various factors which also affect blood pressure such as a person's stress levels or exercise routine. Consider the following cases of advantages of observational studies.
Advantages | Example |
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Measures are taken in real and naturally occurring scenarios. | Observing lions in their environment to learn about roles, eating habits, and social and family structures. |
It is helpful for complex situations, especially those where imposing treatment on individuals could be unethical. | Compare the sugar levels of 50 people who drink coffee and 50 who do not without influencing this decision. |
Observational studies also have disadvantages to be considered.
Disadvantages | Example |
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Risk of ignoring other factors that can affect the variables of the study. | A study might conclude that people who meditate have lower cholesterol levels than others, but it might ignore that they exercise more and follow a healthier diet than others. |
It can be time-consuming, mainly if the observed variables do not occur frequently or last for long periods. | Studying the lifestyle of elephants in their birth and pregnancy stages. Their pregnancy can last around two years and they give birth around every four years. |
In conclusion, consider the context of what is under study to be sure that an observational study is the best methodology for data collection.