L2 - Abnormality***

• What does "normal" mean in medicine?

  Absence of infection, disease, or malformation, or absence of experimental, or therapeutic manipulations.
• According to biostatistical theory, what is normal?

  Total absence of pathological conditions
• What has happened to the medical meaning of "normal" according to Alvan Feinstein?

  It has been lost in the shuffle of statistics
• What is the basis of all comparisons in clinical practice?

  Normality
• What is the significance of distinguishing between normal and abnormal?

  To separate clinical observations from normal findings
• What are the types of abnormalities in medicine?

  • Physical Abnormality
  • Functional Abnormality
  • Biochemical Abnormality
  • Psychological Abnormality
  • Genetic Abnormality
  • Immunological Abnormality
• What is a physical abnormality?

  Unusual physical characteristic detectable by physical examination or medical test.
• What is a functional abnormality?

  Deviation from normal function or behavior. eg; difficulty in performing daily activities, concentrating, memory.
• What is a biochemical abnormality?

  Deviation from normal biochemical parameters. eg; high blood glucose, cholesterol.
• What is a psychological abnormality?

  Deviation from normal psychological function. eg; depression, anxiety
• What is a genetic abnormality?

  Deviation from normal genetic makeup. eg; Down syndrome, sickle cell anemia
• What is an immunological abnormality?

  Deviation from normal immune function. eg; autoimmune disorder, allergies
• What types of patients are found in primary care settings and emergency departments?

  Patients with subtle disease manifestations and healthy complaints
• Why is it important to distinguish between normal and abnormal findings?

  To create a problem list for clinical observations
• What is a problem list in clinical practice?

  A statement of the patient’s important medical problems
• What are the two basic properties used in summarizing distributions?

  Central tendency and dispersion

  
• What is the normal distribution curve?

  A bell-shaped curve representing data distribution
• Why are most distributions of clinical variables not easily divided into normal and abnormal?

  Due to smooth transitions in dysfunction levels
• What criteria can clinicians use to define abnormality?

  Being unusual, being sick, being treatable
• How is being unusual defined?

  By standard deviations beyond 2 from the mean.
• What is the ambiguity in using standard deviations to classify abnormality?

  Extreme values may be common or beneficial
• What does being sick imply in the context of abnormality?

  Having any form of disease indicates abnormality
• What does being treatable imply in the context of abnormality?

  Changes after treatment categorize a person as abnormal
• What is the ways of clinician to distinguish normal from abnormal?

  The data is categorized into how they vary (variation) and then summarized (distribution).
• What are source of variation?

  • Measurement : Instrument and observer
  • Biologic : within and between individuals