3. types of research study

TYPES OF RESEARCH
&
RESEARCH DESIGNS
1Dr. R S Mehta, MSND, BPKIHS
Which is the best type of Research Design?

Types of Study Design:
• There is no best type of study design
• The context, assumptions,
paradigms and perspectives decide
the type of research methodology
Dr. R S Mehta, MSND, BPKIHS 2

Selecting a Research Design
1. Level of knowledge
2. Nature of the research phenomenon
3. Nature of the research purpose
4. Ethical considerations
5. Feasibility
6. Validity and availability of data
7. Precision
8. Cost

4
1. Define the problem ( Characteristics)
2. Specify the objectives (Hypothesis)
3. Select design or type of study
4. Select study population
5. Collect data
6. Analyze data
7. Determine conclusions
Anatomy of Research
Dr. R S Mehta, MSND, BPKIHS

Select design or type of study

Types of Research
From the view point of
Application
Pure
Research
Applied
Research
Objectives
Exploratory
Research
Descriptive
Research
Correlation
Research
Explanatory
Research
Type of Information
Sought
Quantitative
Research
Qualitative
Research

7
TYPE OF STUDIES
Observational
1. Correlational study
2. Case reports and case series
3. Cross sectional survey
4. Case-control study
5. Cohort study
Experimental
1. Community trials
2. Clinical trials – individuals

Study Designs
8
1. Descriptive Studies
2. Cross-Sectional Studies
3. Cohort Study
4. Case Control
5. Randomized Controlled Trials
6. Survey Research

Health Sciences and Nursing Research
Non-interventional Interventional
Explorative
Descriptive
Analytical
Pre-experimental
Quasi-
experimental
True-Experiment
- Case study
- Cross-sectional
- Longitudinal
- Etc.
- Cross-
sectional
- Case control
- Cohort
- Etc
- CRD
- RBD
- FD
- etc
9Note: CRD-complete random design, RBD-random block design, FD- factorial design

4 Types of Research
• Basic research
• Applied research
• Action research
• Evaluation research

Basic Research
• Also known as fundamental research
(sometimes pure research) is research carried
out to increase understanding of fundamental
principles.
• Many times the end results have no direct or
immediate commercial benefits
• Basic research can be thought of as arising out of
curiosity.
• However, in the long term it is the basis for many
commercial products and applied research.
• Basic research is mainly carried out by
universities 11Dr. R S Mehta, MSND, BPKIHS

Applied Research
• Concern with addressing problem of the world
as they are perceived by participants,
organization or group of people
• Action oriented and aims to assess, describe,
document or inform people concerned about the
phenomenon under investigation
• Findings are intended to have immediate and
practical value
• In the field of education, policy, evaluation and
contract are all examples of applied research

Action Research
Action Research is simply a form of self-reflective
enquiry undertaken by participants in social
situations in order to improve the rationality and
justice of their own practices, their understanding of
these practices, and the situations in which these
practices are carried out.
Wilf Carr and Stephen Kemmis (1986)

Evaluation research
• Major concern is practical application
• Tends to be viewed as an isolated case study
though the methodologies may be transferable
• Rooted in values and politics
• Is immediately prescriptive based upon logic and
experience
• Reports are written for implementers, users and
other interested people
• The extent of dissemination is controlled by
sponsor

RESEARCH DESIGNS
QUANTITATIVE QUALITATIVE
• Experimental study
• Quasi-experimental
• Survey study
• Correlational study
• Ethnography
• Case study
• Historical study

Types of Study Design:
Details

1. Descriptive Studies:
Person, Place and
Time

Descriptive Epidemiology
• Includes activities related
to characterizing the
distribution of diseases
within a population
18
• Concerns activities related to identifying
possible causes for the occurrence of
diseases

Descriptive Epidemiology
19
PERSON
PLACE
TIME
Think of this as the standard
dimensions used to track the
occurrence of a disease.

Descriptive Research Design:
–Describe facts
–Discover new facts
–Not invent new theory and methods
–Largest effort given on data
collection
–It answers questions: satisfy
curiosity
–Solve problems

2. Cross-Sectional Studies

Features of C-S Studies
22
• Snapshot in time
–e.g. - cholesterol measurement and
ECG measured at same time
• Determines prevalence at a point in
time
• Therefore, C-S is a prevalence study

Advantages of C-S Studies
23
• Short term
• Fewer resources required
• Less statistical analysis
• More easily controlled
• Design less complex

Advantages of C-S Studies (Cont.)
24
• Provide relationship between
attributes of disease and
characteristics of various groups, e.g.
elderly group
• Data is useful for planning of health
services and medical programs

Disadvantages of C-S Studies
25
• Represent only those who are surveyed
• Identify prevalence, not incidence
necessarily
–excludes cases that died before study
was done
• Show association with survival - not risk of
development

Disadvantages of C-S Studies (cont.)
26
• People who are ill may not show up for
survey -*Healthy Person Effect
• Often, not possible to establish temporal
relationship between exposure and onset
–e.g. does high cholesterol precede CHD?
• Not too effective if disease levels are low,
as difficult to establish a causal relationship

Cross-Sectional Study
27
ineligible
physically active
&
CHD
physically active
&
no CHD
physically inactive
&
CHD
physically inactive
&
no CHD
participation no participation
eligible
Farmers

Cross-Sectional Study
28
Disease
Exposure yes no total
yes a b a + b
no c d c + d

3. Cohort Study

30
Group by common characteristics
Start with a group of subjects who lack a
positive history of the outcome of interest
yet are at risk for it (cohort).
 Think of going from cause to effect.
The exposure of interest is determined for
each member of the cohort and the group
is followed to document incidence in the
exposed and non-exposed members.
Cohort Studies

When is a cohort study warranted?
31
• When good evidence suggests an
association of a disease with a
certain exposure or exposures.

32
Changes and variation in the disease
or health status of a study population
as the study group moves through
time.
“Generation effect”
Cohort Effect

33
• Prospective (concurrent)
• Retrospective (historical)
• Restricted (restricted exposures)
Types of Cohort Studies

34
Types of Cohort Studies
Prospective – cohort characterized by
determination of exposure levels (exposed vs. not
exposed) at baseline (present) and followed for
occurrence of disease in future
 Groups move through time as they age
Retrospective - makes use of historical data to
determine exposure level at some baseline in the
past and then determine subsequent disease
status in the present.
Restricted - limited exposure, narrow behavior
(e.g. military)

Advantages of
Prospective Cohort Studies
35
• Large sample sizes
• Certain diseases or risk factors targeted
• Can be used to prove cause-effect
• Assess magnitude of risk
• Baseline of rates
• Number and proportion of cases that can be
prevented

Advantages of
Prospective Studies (cont’d)
36
• Completeness and accuracy
• Opportunity to avoid condition being
studied
• Quality of data is high
• Considers seasonal and other variations
over a long period
• Tracks effects of aging process

Disadvantages of Prospective
Cohort Studies
37
• Large study populations required
– not easy to find subjects
• Expensive
• Unpredictable variables
• Results not extrapolated to general population
• Study results are limited
• Time consuming/results are delayed
• Requires rigid design and conditions

Disadvantages of
Prospective Studies (cont’d)
38
• Subjects lost over time (dropouts)
• Costs are high
• Logistically demanding
• Maintaining quality, validity, accuracy
and reliability can be a problem

4. Case Control Study

CASE-CONTROL STUDIES
SOME KEY POINTS
40
• Frequently used study design
• Participants selected on the basis of whether or
not they are DISEASED (remember in a cohort
study participants are selected based on
exposure status)
• Those who are diseased are called CASES.
• Those who are not diseased are called
CONTROLS.

Case-Control Design
41
Subjects With
Outcome of Interest
Design
Appropriate
Control Group
Without Outcome
Of Interest
Measure
factors
Compare
factors

MATCHING
42
• CHARACTERISTICS OFTEN USED
–age
–gender
–body mass index (weight / height2)
–smoking status
–marital status

MATCHED PAIRS EXAMPLE
43
CASE
CONTROL
CASE
CONTROL

Example: Hypothetical data
44
Cases Controls
Exposed 141 133
Unexposed 1250 4867
Total 1391 5000
ODDS RATIO = 141 * 4867 = 4.13
133 * 1250Dr. R S Mehta, MSND, BPKIHS

Interpretation of the Odds Ratio…
45
If:
OR = 1 then exposure is NOT related to disease
OR>1 then exposure is POSITIVELY related to
disease
OR<1 then exposure NEGATIVELY related to
disease

Interpretation:
46
The odds that those with the
outcome had the exposure is 4.13
times greater than those who do
not have the outcome

Strengths:
47
1. Quick and inexpensive
2. Well-suited to the evaluation of outcomes
with long latent periods
3. Optimal for the evaluation of rare diseases
4. Can examine multiple etiologic factors for a
single disease

Limitations:
48
1. Cannot directly compute incidence rates
of disease
2. Temporal relationship between exposure
and disease may be difficult to establish
3. Prone to bias
4. Insufficient to evaluate rate exposure

5. Randomized Controlled Trials

Randomized Controlled Trials
50
• Similar groups of individuals from same
source population are allocated at random to
receive or not to receive an intervention, then
observed for occurrence of outcome(s).
DESIGN
Subjects
with
condition of
Interest
Experimental
Group
Control
Outcome
Outcome

51
A Factorial RCT for Two Studies for the Price of One

Randomized Controlled Trial : Advantages
52
1. Comparability due to randomization and same
effect of known and unknown confounders gets
eliminated
2. Experiments provide strong evidence of cause
and effect.
3. Allows standardization of eligibility criteria,
maneuver and outcome assessment.
4. Allows use of statistical methods with few inbuilt
assumptions.

Randomized Controlled Trial
: Disadvantages
53
1. May be expensive in terms of time, money and
people.
2. Many research questions are not suitable due
to ethics, likely co-operation or rarity of
outcome.
3. To a greater or lesser extent RCT tends to be
an artificial situation.

6. Survey Research

Planning a Survey
55
• Deciding on a research question
• Choosing the format of your questions*
• Choosing the format of your interview--if
you use an interview*
• Editing your questions*
• Sequencing your questions*
• Refining your survey instrument*
• Choosing a sampling strategy*

Editing Questions: Nine Mistakes to Avoid
56
1. Avoid leading
questions
2. Avoid questions
that invite the
social desirability
bias
3. Avoid double-
barreled questions
4. Avoid long
questions
5. Avoid negations
6. Avoid irrelevant
questions
7. Avoid poorly
worded response
options
8. Avoid big words
9. Avoid ambiguous
words & phrases

7. Case Study
• Explores in depth a program, event, activity,
process, or one or more individuals
• Bounded (separated out for research) by time,
place and activity
• Researcher collects detailed information using a
variety of data collection procedures over a
sustained period of time (Stake, 1995; Creswell,
2007)
• A method of learning about a complex instance
based on a comprehensive understanding of that
instance obtained by extensive description and
analysis of that instance taken as a whole

8. Historical Study
• Focuses primarily on the past
• Persuing documents of the period
• Examining relics (reminders)
• Interviewing individuals who lived during that time
• Reconstruct what happened during that time as
completely as possible
• Systematic collection and evaluation of data to
describe, explain, and thereby understand actions
or events that occurred in the past
• No manipulation or control of variables

59
9. Experimental Research Designs

Experimental Design
• It is a collection of research designs which
use manipulation and controlled testing to
understand causal processes.
• Generally, one or more variables are
manipulated to determine their effect on a
dependent variable.
• Test whether an educational practice or
idea makes a difference for individuals

Aim:
• The aim of experimental research is to
investigate the possible cause and effect
relationship by manipulating one
independent variable to influence the other
variable in the experimental group and by
controlling the other relevant variables and
measuring the effects of the manipulation
by some statistical means.

Characteristics or Features of
Experimental Design
1. Manipulation
2. Control
3. Randomization

Experimental Design
• Advantages
– Best establishes cause-and-effect
relationships
• Disadvantages
– Artificiality of experiments
– Feasibility
– Unethical

Types of Experimental Designs
• True-Experimental (Simple)
• Quasi-Experimental
• Pre-Experimental

True, Qusi, & Pre- Experimental Study
Randomization, Control and Manipulation
• True exp.: All 3: R C M
• Quasi exp.: M + R or C
• Pre exp.: M, no R & no C

10. Ex Post Facto Study
• Variable of interest is not subject to direct
manipulation but must be chosen after the
fact.
E.g., Define two groups of people according to
a certain characteristic (e.g., history of trauma)
and measure how they respond in terms of
anxiety to a certain stimulus (e.g., watching
violent film).
• Limitation – self-selection bias, cohort effects
may explain the effect.

11. Meta Analysis
67
• Statistically combines results of existing
research to estimate overall size of
relation between variables
• Helps in
• Developing theory
• Identifying research needs,
• Establishing validity
• Can replace large-scale research studies
• Better than literature reviews

12. Qualitative Research

Choice of Colours
• 1. What colour would you like the most?

2.What do you associate this colour with?
Good luck
love
Confidence
Truthfulness
Lively
Danger
…

3. What is the source of this knowledge?
–Own Idea
–Own Belief
–Own observation
–Own experiences
–Cultural and Traditional
–Books & articles
– etc

• Not every thing can be quantified.
• Some valuable ideas, opinions,
perceptions, experiences,
behaviours, qualities can be
described only in words
• These subjective things are shared
between people, but the meanings
may be distorted in the process of
communication and recording.

• Although subjective, these
aspects often add richness
and depth
• The art of the doctor and the
experience of being human
are aspects that need a
qualitative approach to
investigate/research
properly. 73Dr. R S Mehta, MSND, BPKIHS

Definitions
• Quantitative Research - investigation in which
the researcher attempts to understand some
larger reality by isolating and measuring
components of that reality without regard to their
contextual setting.
• Qualitative Research - investigation in which the
researcher attempts to understand some larger
reality by examining it in a holistic way or by
examining components of that reality within their
contextual setting.

Qualitative Research
• ‘Qualitative Research…involves finding out what
people think, and how they feel - or at any rate,
what they say they think and how they say they
feel. This kind of information is subjective. It
involves feelings and impressions, rather than
numbers’
• Bellenger, Bernhardt and Goldstucker, Qualitative Research in
Marketing, American Marketing Association

Qualitative Research
– Human understanding and
interpretation define reality
– Complex reality can be understood and
not as simply a sum of its parts
– Goal of research is to examine complex
phenomena to define the reality within
– To be meaningful, inquiry must be holistic
and contextual

Universal
Specific
Explanatory
Descriptive Subjective
Objective
Universal ------------------------------ Specific
Objective ------------------------------ Subjective
Explanatory ---------------------------- Descriptive

Characteristics of Qualitative Research
• Purpose is understanding
• Oriented toward discovery
• Uses subjective data
• Extracts meaning from data
• Interprets results in context
• Focus is holistic

Disadvantages of Qualitative Research
• Subjectivity leads to procedural problems
• Replicability is very difficult
• Researcher bias is built in and unavoidable
• In-depth, comprehensive approach to
data gathering limits scope
• Labor intensive, expensive
• Not understood well by “classical”
researchers

Organizational Structures
(Types)
Historical Analysis
Ethnography
Phenomenology
Life History,
Chronology,
Historiography
Case Study

Ethnographic Design
• Examining a group of individuals in the setting where
they live and work, and in developing a portrait of how
they interact
• Describing, analyzing and interpreting a group’s shared
patterns of behavior, beliefs and language that develop
over time
• Provides a detailed picture of the group, drawing on
various sources of information
• Describes the group within its settings, explores themes
or issues that develop over time as the group interacts
• Data analysis emphasize on description and explanation
rather than quantification and statistical analysis
(Atkinson & Hammersley, 1994) 81Dr. R S Mehta, MSND, BPKIHS

Phenomenology
• Definition: “Phenomenology is an approach
which attempts to understand the hidden
meanings and the essence of an experience
together with how participants make sense of
these.” (Grbich 2007, p. 84).
• Strengths: Phenomenology is used to explore,
describe, document rich details of people’s
experiences, especially changes in feelings and
experiences over time.

Phenomenology…
•Epistemological position --
Interpretivism.
Husserl : Experience is the source of all
knowledge.
•Common Research methods: In-depth
Interview as well as observation and
documentation.

Advantages of Qualitative Research
 In-depth Examination of Phenomena
(Phenomenological Study/Research)
 Uses subjective information
 Not limited to rigidly definable variables
 Examine complex questions that can be impossible
with quantitative methods
 Deal with value-laden questions
 Explore new areas of research
 Build new theories

Disadvantages of Qualitative Research
 Subjectivity leads to procedural problems
 Replicability is very difficult
 Researcher bias is built in and unavoidable
 In-depth, comprehensive approach to
data gathering limits scope
 Labor intensive, expensive
 Not understood well by
“classical” researchers

Review: Health Sciences and Nursing Research
Non-interventional Interventional
Explorative
Descriptive
Analytical
Pre-experimental
Quasi-
experimental
True-Experiment
- Case study
- Cross-sectional
- Longitudinal
- Etc.
- Cross-
sectional
- Case control
- Cohort
- Etc
- CRD
- RBD
- FD
- etc
86Note: CRD-complete random design, RBD-random block design, FD- factorial designDr. R S Mehta, MSND, BPKIHS

Relative strength of various study designs
(based on level of evidence for a cause &
effect relationship)
87
Strength Design
Strong Clinical trial
Cohort study
Case control study
Cross sectional
Case series
Weak Case report

Websites, Search Engine, and
address of Journals
• www.pubmed.com
• www.google.com
• www.yahoo.com
• www.msn.com
• www.rn.com
• www.who.int (WHO website)
• www.randamization.com
• www.tnaionline.org (TNAI Journal)
• www.hellis.org (NHRC library site)
• www.kumj.com.np
• www.nhrc.org.np
• www.uicc.org (cancer website)
• www.unaids.org (HIV/AIDS website)
• www.ncasc.org.np (HIV/AIDS website)
• www.healthinternetwork.org (HINARI: needs password)
• www.blackwell-synergy.com (need passwords)
• www.doaj.org (free online journal) Dr. R S Mehta, MSND, BPKIHS 88

Some Popular Resource Sites for Nurses
• www.delicious.com
• www.connotea.org
• www.scribd.ocm
• www.authorstream
• www.zotero.org
• www.scratch.mit.edu
• www.myebook.com
• www.forvo.com

“The beautiful thing about
learning is that nobody can
take it away from you.”
--BB King
Thank-You 90

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