Public health is all about promoting the health of a population and preventing the onset of illnesses among individuals or groups of individuals. As such, public health practitioners must recognize the variation that lies within any group of persons. Essentially statistics are part of public health practice. We hope that this course will give you a stronger understanding of the language and logic of statistical analysis and interpretation of quantitative data.

Why is Statistics Important in Public Health?
We use statistics all the time in public health. We keep records of events (births, deaths, infections, etc.). In most situations, when trying to understand these recorded events, we naturally start talking about trends or averages. Statistics give us an approach to do this more systematically and accurately. For instance, we can use statistics to determine when the variation in a group is greater than expected. Statistics also provides a common language for us to communicate these findings to others.
We also use statistics when we read quantitative research papers or evaluate reports. Many papers speak about "significant" results and provide "p-values" as justification. As public health practitioners, we can use statistics to critically appraise these articles and see if the statements accurately reflect the data. From a statistician's point of view, the most important part of a paper is the methods and analysis portion. It is here one learns whether or not the hypotheses and results put forth by the authors are indeed worthy of being called "significant". Hence, this course will help you move from simply perusing an article and accepting the findings to critically appraising the study. A detailed review of critical appraisal goes beyond this course, but understanding the fundamentals of statistical analysis is an important skill and a learning objective for this course.

Purpose:
This course will provide a basic understanding of statistics so that you can read, review, interpret, and appraise literature (academic journal articles and grey literature) as well as apply basic statistical analyses with common public health data. Learning materials focus on providing a common language and understanding of statistical concepts, without detailed mathematical formulas. The intent is to provide you with the language and basic concepts of statistics and to enable you to know when and how to communicate with a statistician in a way that is beneficial to both of you. For further statistical support, we recommend connecting with epidemiologists in your public health unit and/or at Public Health Ontario.

Prerequisite:
To get the most out of this course, you will need a basic understanding of the fundamentals of epidemiology and an understanding of high school mathematics. You will be working with rates, and so will require some knowledge in the use of ratios, proportions, crude, specific and adjusted rates; incidence and prevalence; defining health and health status; assessing the health of a community using selected indicators of health status; and interpreting various types of data. Therefore we recommend that you have completed PHESC Introduction to Epidemiology as a prerequisite for this course.

Learning Outcomes:

• Understand the basics of statistics as applied to epidemiology and public health, including being able to discuss the uses and limitations of commonly used statistical analyses.
• Apply simple statistical procedures where appropriate.
• Use statistical principles in order to critically appraise an article from a quantitative perspective.