Statistics is used to:
       • Describe data – descriptive statistics
       • Compare study groups 
       • Search for any correlation between variables
       • Search for a regression between variables 
         in order to extrapolate the dependent variable 
         if independent variable(s) is(are) known
       • Analyze health outcomes
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       Overview of Presentation
        Which test to use?
        Parametric assumptions
        Non-parametric tests
        ANOVA (Analysis of variance)
        Correlation
        Dependent vs independent variables
        • The dependent variable represents 
            • the output or 
            • the effect, or 
            • is tested to see if it is the effect. 
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         Dependent vs independent variables
         • The independent variable is the variable that 
            • you have control over, what you can choose 
              and manipulate. 
            • is usually what you think will affect the dependent variable. 
         • In some cases, you may not be able to manipulate the independent 
          variable. 
            • It may be something that is already there and is fixed, like color, kind, time;
            • something you would like to evaluate with respect to how 
              it affects the dependent variable.
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       Which statistical test(s)?
       1. How many study groups are there?
         •  One
         •  Two
         •  More than two
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