1. Statistical planning and Sample size determination

2. Planning Which variables will I collect and how will they be measured? What types of data do they represent? What do I want to do? Describe, compare groups, predict change in Y following change in X? How large a sample do I need to find a clinically important difference statistically significant???

3. Dummy analysis How will I describe my data? What hypothesis tests will I be doing?

4. Sample size

5. Descriptive study Here the sample size will determine the precision of the study (the confidence interval) Small study>>>> wide CI Large study>>>>narrow CI Here power and P values are not relevant

7. Mean 120 mmHg Sd 20 mmHg What sample size needed for CI to be ± 2.2

8. Hypothesis testing Studies where we test hypothesis eg compare groups regarding means or proportions or test significance of correlation or regression coefficients

9. Type 1 and 2 error

11. Method 1 Working with standardised difference and nomogram Method 2 Working with 2 means and Sd or working with two proportions

15. N=130 One tailed table (must X 2)

19. Use same nomogram N=3000 in total

22. Examples