�ݺ�ߣ

Selecting a Study Design
Kumar: Research Methodology
Chapter 8
Prepared by Stephanie Fleischer
authored by Stephanie Fleischer © SAGE publications Ltd 2014

Topics covered
• Differences between quantitative and
qualitative study designs
• Common study designs in quantitative
research
• Common study designs in qualitative research
• Other philosophy-guided designs
authored by Stephanie Fleischer © SAGE publications Ltd 2014

Differences between quantitative and
qualitative study designs
• Quantitative studies
designs:
• - are more used
– Specific
– Rigid
– Well structured
– Ensure validity and
reliability
• Qualitative research
designs:
– Less used
– Flexible
– Emergent
– Unstructured
– Non-sequential
– freedom
Differences in philosophical perspectives determine the
approach of enquiry
authored by Stephanie Fleischer © SAGE
publications Ltd 2014

• The main focus in qualitative research is to understand,
explain, explore, discover and clarify situations, feelings,
perceptions, attitudes, values, beliefs and experiences of
a group of people.
• The study designs are therefore often based on
inductive rather than deductive logic, are flexible and
emergent in nature, and are often non-linear and non-
sequential in their operationalisation
• The study designs mainly entail the selection of people
from whom the information, through an open frame of
enquiry, is explored and gathered.
• In qualitative research there is an overlap between the
two. Some designs are basically methods of data
collection.
• For example, in-depth interviewing is a design as well as
a method of data collection, oral history, and participant
observation.
• In qualitative research, the researcher seeks the
agreement of his respondents with his interpretation,
presentation of the situations, experiences, perceptions
and conclusions.
• The ‘power-gap’ between the researcher and the study
population in qualitative research is far smaller,
• In qualitative research little attention is paid to study
designs, hence the replication of a study design
becomes almost impossible.
• In qualitative research findings cannot be easily tested.
• Bias is possible
• Study designs in qualitative research are more appropriate
for exploring the variation and diversity in any aspect of social
life
• ‘how many people have a particular value, belief, etc.?’,
• in quantitative research, the measurement and
classification requirements of the information that
is gathered demand that study designs are more
structured, rigid, fixed and predetermined in their
use to ensure accuracy in measurement and
classification.
• Quantitative study designs have more clarity and
distinction between designs and methods of data
collection
• In quantitative research respondent concordance
does not occupy an important place.
• The ‘power-gap’ between the researcher and the
study population in quantitative research is far
greater
• In quantitative enough detail about a study design
is provided for it to be replicated for verification
and reassurance.
• Findings through quantitative study designs can be
replicated and retested,
• Bias is not possible
• in quantitative research they are more suited to
finding out the extent of this variation and
diversity.

Study designs in quantitative research
Study designs can be classified by examining
from three different perspectives:
1. The number of contacts with the study
population
2. The reference period of the study
3. The nature of the investigation
authored by Stephanie Fleischer © SAGE

Study designs based on the number of
contacts
• Cross-sectional: most commonly used in social
sciences and take a cross-section of the
population at one point in time
• Before-and-after: also known as pre-test/post-
test design which take two cross-sectional data
collection points on the same population to find
out changes.
• Longitudinal: the population is researched a
number of times; a series of repetitive cross-
sectional studies collecting the same information
authored by Stephanie Fleisher © SAGE

A cross-sectional study is extremely simple in design. You decide what you
want to find out about, identify the study population, select a sample (if you
need to) and contact your respondents to find out the required information

• The main advantage of before-and-after design is its
ability to measure change in a phenomenon or to assess
the impact of an intervention. However, there can be
disadvantages which may not occur, individually or
collectively, in every study.
• These disadvantages include the following
• As two sets of data must be collected is more expensive and more
difficult to implement.
• the time lapse between the two contacts may result in attrition in the
study population. i.e. withdrawal.
• it is not possible to quantify the contribution of independent and
extraneous variables separately.
• If the study population is very young and if there is a significant time
lapse between the before-and-after sets of data collection changes in
the study population may be because it is maturing.
• Sometimes the instrument itself educates the respondents. This is
known as the reactive effect of the instrument.
• is a possible shift in attitude between the two points of data collection.

Study designs based on the reference
period (time-frame)
• Retrospective: investigate things that
happened in the past
• Prospective: investigate things that are likely
to happen in the future, such as experiments
• Retrospective-prospective: focus on both past
trends and study it into the future, such as
before-and-after studies without a control
group

Study designs based on the nature of
the investigation
• Experimental: starting from the cause to
establish the effect; the researcher
introduces the intervention that is
assumed to cause the change in a
controlled or natural environment.

Experimental designs
• Random design
• The after-only design
• The before-and-after experimental design
• The control group design
• The double control group design
• The comparative design
• The ‘matched control’ experimental design
• The placebo design

Study designs based on the nature of
the investigation - continued
• Non-experimental: Starting with the effect to
research the cause; a phenomenon is known
and the researcher attempts to establish what
caused it.
• Quasi- or semi-experimental: This design has
elements of both experimental and non-
experimental studies.

Figure 8.1 Types of study design

Other quantitative designs
• Online surveys
• The cross-over comparative experimental design
• The replicated cross-sectional design
• Trend studies
• Cohort studies
• Panel studies
• Blind studies
• Double-blind studies

Study designs in qualitative research
• Case studies: In-depth exploration of a
atypical case of a particular event, group,
instance, etc.
• Oral history: Obtaining, recording, presenting
and interpreting information in someone’s
own words
• Focus groups/ group interviews: Facilitated
group interviews of an open discussion of a
topic

Study designs in qualitative research
continued
• Participant observation: Researcher gets
involved in a social interaction and observes
the situation first hand
• Holistic research: More a philosophy, research
from every perspective
• Community discussion forums: Large group
discussion
• Reflective journal log: Diary of the
researcher’s thoughts

Other philosophy-guided designs
• Action Research: Research that requires action to
improve practice or take action to an issue
• Feminist research: Underpinned by feminist
concerns in terms social inequality between men
and women
• Participatory and collaborative research enquiry:
Based on the philosophy of community
development involving community members
actively in the research process

�ݺ�ߣ

Chapter 8.pptx

Recommended

More Related Content

Similar to Chapter 8.pptx (20)

Recently uploaded (20)

Chapter 8.pptx