This document provides an overview of research methods and sampling techniques. It discusses the differences between probability and non-probability sampling, and describes common probability sampling methods like simple random sampling. The document also summarizes different approaches to systematic reviews, including traditional systematic reviews primarily used in medicine, mixed methods reviews that incorporate qualitative research, and integrative reviews focused on theory building. Finally, it outlines the typical steps involved in undertaking a systematic review project.
2. What is Sampling?
• It is about choosing who or what we wish t
study in order to answer our research
question.
• It could be chosen randomly and
purposively.
• It has a major impact on our results, so
should be done thoughtfully and with a
clear rationale.
3. QUANTITATIVE RESEARCH
Researchers use
probability or random
sample for the statistical
processes they
undertake.
QUALITATIVE RESEARCH
Researcher use non-
probability sampling
because of their
research’s nature: largely
exploratory.
4. What is a Sample?
• Every person from the population under
study.
• Representatives that were chosen in such
a way that subjects or cases have
similarity of beliefs, attitudes or
experiences to those of the population
being investigated.
5. Probability Sampling
• Sampling in which each unit of the
population has an equal or known chance
of being selected for study.
• The sample is chosen from the sampling
frame in an unbiased and rigorious way.
• It allows a high degree of
representativesness from which results
can be generalised.
• Its types are simple random, systematic
random, stratified random and cluster
random sampling.
6. Simple Random Sampling
• The most common form of probability
sampling.
• Sample may be chosen in a number of
other ways, including by dates of birth or
by initials.
• Any randomized technique is suitable.
• Sample is generated.
8. Traditional Systematic Review
• First approach developed and was
originated in medicine and clinical
sciences.
• It follows a rigorous set of steps with a
hierarchy of evidence.
• Data presented are summaries of the
articles selected for inclusion which are
tabulated and presented.
• Takes a great deal of time and resources
9. Mixed methods or extended
reviews
• Adapts the traditional systematic review for
social sciences to include a wide range of types
of research.
• Includes more qualitative research which tends
to put qualitative findings at the bottom of the
evidence hierarchy.
• Includes research about processes and people’s
perception or experiences.
• More flexible and criticisms are transparent and
lose the clear focus of traditional approaches.
10. Integrative or ‘critical
interpretive synthesis’ reviews
• Focuses on theory-building and use
qualitative methodology.
• Can include all types of research
evidence.
• Don’t have to be comprehensive
• Might be less transparent than the other
two approaches.
11. Steps in undertaking a
systematic review
1. Define the
question/s, scope
and protocols for the
review.
2. Search the literature.
3. Assess the quality of
the included studies
4. Synthesize the
results
5. Report the findings.