Meet my friends……

1. Meet my friends……

2. Chester the T TEST • Comparing means of 2 variables • Exposure-Categorical w/ up to 2 categories • Outcome- Continuous

3. Rova the ANOVA • Comparing means of 2 variables • Exposure- Categorical w/ 3 or more categories • Outcome- Continuous

4. Tory the Correlation • Quantifying association of 2 variables • Exposure & Outcome- Continuous • Positive or Negative? Strong or Weak?

5. Phineas the Linear Regression • Making predictions about 2 variables • Exposure- categorical or continuous • Outcome- continuous

6. Muppy the Multiple Linear Regression • Making predictions about 2 variables while controlling for confounding variables • Exposure- Categorical or Continuous • Outcome- Continuous

7. CHI-LEE the CHI Squared

8. Chi Square Test • Used to test for significant differences when the data is qualitative and dichotomous AKA 2 CATEGORICAL VARIABLES Exposure- Categorical w/ @ least 3 categories Outcome- Category w/ 2 categories

9. So….. • Since I use CATEGORICAL variables.. Descriptive statistic tools used are: Frequency and Percentages

10. Thus I am used: • To see if there are differences in proportions • Not to determine or quantify the differences but just TO SEE IF THERE IS A DIFFERENCE • To look at the frequency of a disease outcome based on a categorical exposure • Variables are independent and mutually exclusive/exhaustive • Random Sample

11. Example • Exposure? • Categories • Outcome?

12. Example Research Hypothesis: The proportions of OUTCOME among EXPOSURE CATEGORIESare significantly different Null Hypothesis: The proportions of OUTCOME among EXPOSURE CATEGORIES are equal.

13. STATA