1. Mother and Child Health: Research Methods G.J.Ebrahim Editor Journal of Tropical Pediatrics, Oxford University Press.

2. Programmes Menu of Epi-Info

3. The Normal Distribution A histogram provides a view of how the values of a variable are distributed.

4. Number of values and the Gausian shape All these histograms illustrate a Normal distribution. As the number increases the Gausian shape becomes more obvious

5. Scatterplot to show relationship between two numeric variables A scatterplot of dose of anaesthetic and time to recover from anaesthesia, with a regression line and 95% confidence intervals as well as outliers.

6. Outliers An outlier is an unusually high value of Y for a given value of X. Outliers exert an influence on the regression line.

7. Rates, Proportions and Ratios Is numerator included in the denominator? Yes Is time included in denominator? YesNo MEASURE: Rate Proportion Ratio EXAMPLE: Incidence Prevalence Maternal Mortality Rate Rate ratio

8. Absolute risk, Probability of survival and Odds ratio Absolute RiskSurvival Probability Odds 0.901−0.90 = 0.100.90÷(1−0.9) =9.0 0.751−0.75 = 0.250.75÷(1−0.75) = 3.0 0.501−0.50=0.500.50÷(1−0.50)=1.0 0.251−0.25=0.750.25÷(1−0.25)=0.33 0.101−0.10=0.900.10÷(1−0.10)=0.11 0.011−0.01=0.990.01÷(1−0.01)=0.01

9. Calculating Numbers Needed to Treat (NNT) Calculate the proportion of people who have the outcome in the intervention group. (Exp.Grp.Evnt Rate; EGER ) Calculate the proportion of people who have the outcome in the control (placebo) group. (Cntrl. Grp.Event Rate; CGER) Calculate the difference between EGER and CGER to obtain Absolute Risk Reduction (ARR) Then NNT = 1÷ARR