INTRODUCTION -- STEP 1. Descriptive statistics - What we can learn aboutthe patients? -- STEP 1 - exercise. Preliminary data analysis -- STEP 2. We analyse the distribution of the measurablevariable -- STEP 2 - exercise. Data analysis -- STEP 3. The χ2 (chi-square) test of the goodness of fit -- STEP 3 - exercise. Checking the type of distribution -- STEP 4. T-test and F-test. How to estimate the differences between groups of patients? -- STEP 4 - exercise. F-test and T-test -- STEP 5. ANOVA test. How to compare more than two groups? -- STEP 5 - exercise. ANOVA test -- STEP 6. Correlation and regression. Are any variables mutually dependent? -- STEP 6 - exercise. Correlation and regression -- STEP 7. The Pearson's χ2 (chi-square) test. (The χ2 independence test). Is there any relation between qualitative variables? -- STEP 7 - exercise. χ2 (chi-square) test of independence -- STEP 8. Nonparametric tests (distribution-free tests). How about the data not representing the normal distribution? -- STEP 8 - exercise. Nonparametric tests (distribution free tests) -- STEP 9. COMPREHENSIVE ANALYSIS -- THE SUMMARY OF COMPREHENSIVE ANALYSIS -- STEP 9 - exercise. COMPREHENSIVE ANALYSIS -- STEP 10. Survival analysis - Is it possible to make prognosis? -- STEP 10 - exercise. Survival analysis -- RECAPITULATION -- AFTERWORD -- SUPPLEMENTARY TABLES -- VOCABULARY -- INDEX -- CONTENTS.