Therapy: Fundamental Concepts

  • Kameshwar Prasad


Health practitioners are rightly interested to know whether a new treatment works, whether it makes any difference, difference in what, in the outcome of his case or the prognosis of his patient. But there is a problem. The problem is that there are many factors which influence the outcome in a given patient. Some such factors are called prognostic factors, like age, sex, nature of the disease, disease severity, and co-morbidities. The other factors are biases and chance. If we can eliminate these factors and other treatments as the possible cause of a particular outcome, then we can be sure that the new treatment given to the patient has caused the outcome – whether beneficial or adverse. But it is impossible to eliminate the role of these factors. Hence it is difficult, if not impossible, to know for sure whether a given treatment makes a difference in the outcome. Researchers use several strategies to control these extraneous factors; one of which is to use a control group.


Null Hypothesis Systolic Blood Pressure True Effect Risk Difference Malarial Parasite 
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Copyright information

© Springer India 2014

Authors and Affiliations

  • Kameshwar Prasad
    • 1
  1. 1.Department of Neurology Neurosciences Centre, and Clinical Epidemiology UnitAll India Institute of Medical SciencesNew Delhi DelhiIndia

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