Mother and Child Health: Research Methods

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

2. Basic Design of Clinical Trials Cured Same Treatment Sample Randomise Blinding Placebo Cured Same Subjects Blocking

3. Variations in Basic Design -1 Run-in Design Admission On placebo Compliers randomised A S S E S S A S S E S S Cross-over Design Treatment 1 Recruitment Randomised Treatment 2

4. Variations in Basic Design - II Time - Series Design No Treatment Recruitment Treatment Treatment Assess Assess Assess Low Dose Factorial Design Treatment 1 High Dose Recruitment Randomise Treatment 2 Low Dose High Dose

5. Issues of Methodology - I Entry Criteria Strict for Explanatory Trials. Less strict for Pragmatic Trials Diagnosis How accurate? Interventions How good a compliance achieved? Subjects who drop-out are different from those who continue Other competing interventions?

6. Issues of Methodology - II Subject Allocation Different rates of drop-out between groups cause under or over estimate of outcome. Treatment Allocation Randomisation and blinding help to remove bias. Blocking needed if outcomes vary because of age, sex or other attributes.

7. Challenges in Designing Clinical Trials Control of Bias - In allocation of subjects to treatment. In assessment of outcome. Sample Size How small a difference is clinically important? What tests of significance will be used? What outcome is expected in the control group? Drop-outs and Withdrawals How to handle them during analysis?

8. Generalizability of Results Treated Outcome Sample Population of Patients Control Outcome Difference in Outcome by Chance? Rigour of study Other Populations Generalisability