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

Elements of the Scientific Method l Observation, description and measurement l Generalisation l Hypotheses l Theories l Deduction l Controlled Observation l Verification / Falsification

Observation, Description and Measurement Precise, unbiased recording of observation is the hallmark of science. The data so obtained could be Quantitative or Qualitative

Generalisation Statements arising out of observation are often generalised. For example, “Penicillin cures pneumonia.” This is known as Induction

Hypotheses Hypotheses are statements which specify the nature of relationships between 2 or more sets of observations. For example, Observation set 1 Administration of penicillin. Observation set 2 Cure of pneumonia.

Theories Hypotheses get integrated into theories. Theories bring together observations from many sources. For example, microbiology; cell physiology, medicine, and so on. Theories specify causes of events and help to predict events and outcomes.

Deduction Deductions are Logical Statements arising out of theories

Controlled Observation Hypotheses are tested under controlled conditions to remove the influence of other factors

Verification / Falsification The investigator collects data, and after analysis decides whether the results are consistent with the hypothesis. Observations Hypotheses Theories

The Research Process Phenomenon of Interest Research Question Target Population Study Plan Operational Variables Sample Population Actual Study Actual Data Actual Subjects Findings in the Study Truth in the study Truth in Universe

Sources of Distortion Research Question Target Population Phenomenon of Interest Study Design not Appropriate Study Population Different from target population Operational variables not Appropriate

Internal and External Validity Sample Target Population Sample Sampling Comparison Measurem ent Analysis Conclusion Internal validity External Validity