1. STUDY DESIGN
Lucy Au, James Macphersn
DWU
lau@dwu.ac.pg; jmacpherson@pngfire.gov.pg

2. RESEARCH DESIGN
Provides framework by which a
study will answer research
questions
Guides researcher (as recipe
guides a cook)
Provides signposts to guide
researchers through research

3. STUDY DESIGNS
To assess association between
variables the study must be
comparative
The design should avoid potential
biases
Observational – describe the
variable but not associations

4. TYPES OF STUDIES
Observational (descriptive)
Intervention (experimental)
E.g. assess association between
smoking and health – imagine
experimental study design, ideal
but unethical, that is why they
chose case-control (descriptive)

5. Factors to be considered in design
• objectives and major research questions
• study hypotheses: what data are required to
accept or reject a hypothesis
• data to be collected
• plans analysis and dummy tables so no
important information is missed
• target population: age, sex, religion,
language
• will respondents give required answers?

6. CHECK UP POINTS FOR STUDY DESIGN
 Is the hypothesis/ research questions/
focus area clearly stated?
 Is the study going to harm the patient
or institution?
 Are outcome measures clear and
measurable?
 Is the sample size going to be
statistically significant?

7. WHAT IS THE BEST
RESEARCH DESIGN?
No one answer
Bestfit and answer your
research questions

8. COMPARISON OF MAJOR RESEARCH DESIGN
Simple Comparative Correlational Quasi-
descriptive descriptive experimental
Describes Yes Yes Yes Yes
participants
Compares No Yes Yes Yes
group
Investigates No No No Yes
cause-effect
Manipulates No No No Yes
independent
variable
Control group No No No Yes
Random No No No No
assignment

9. TRIANGULATION
 Methodological – use more than 1
technique to gather information, e.g.
interview + observation + group discussion
+ documents examination; or quantitative
and qualitative
 Data triangulation – different space, person
at different level (individual, group)

10. EXERCISES
 Which design is appropriate?
 A. simple descriptive
 B. descriptive comparative
 C. correlational design
 Is diabetes more common in obese people
than in people with normal weight?
 Do treated mosquito nets reduce incidence
of malaria?
 What is the prevalence of TB in X area?