Medical Statistics Overview

Medical Statistics

• Medical statistics is the science of collecting, presenting, analyzing, and interpreting data in medical practice. It's used to estimate the significance of associations and test hypotheses.

Functions of Statistics

• Presenting data in a simple and understandable format.
• Comparing health status of different locations or in one place at different times.
• Diagnosing health problems within a community.
• Evaluating health programs (e.g., vaccination programs).

Data

• Data is a set of values from one or more variables, recorded in observation units. This can describe quantitative or qualitative aspects of things.

Types of Data

• Constant: Observations that don't vary from person to person (e.g., number of chromosomes in a gene).
• Variable: Observations that vary from person to person.

Variables

• Quantitative: Expressed numerically, can be continuous or discontinuous.

  • Continuous: Can take on any value within a given range (e.g., weight, height).
  • Discontinuous (discrete): Can only take on specific values (e.g., number of cells, number of microbes per cubic centimeter).

• Qualitative (categorical): Variables without a natural order.

  • Measured on a nominal scale (e.g., hair color, name, religion).
  • Ordinal: Categories can be ordered (e.g., education level, socioeconomic status).

Data Collection

• The process of collecting and measuring data in a systematic way, enabling answering of questions and evaluation of outcomes.

Methods of Data Collection

• Historical Records:
  • Censuses
  • Vital statistics
  • Epidemiological records
  • Scientific journals and textbooks
• Experimental Studies
• Surveys:
  • Comprehensive: Data gathered from every member of a community (e.g., small community like a school, village, or factory).
  • Sample: Data gathered from a representative sample of a population to generalize results to the whole population; the sample must be large and well-chosen to be representative.