RESEARCH METHODOLOGY by DR SURBHI NARAYAN

RESEARCH
METHODOLOGY
DR SURBHI
FNB MAHAVIR CANCER SANSTHAN

Research is a logical and systematic search for new and
useful information on a particular topic.
An investigation for finding solutions to scientific and social
problems through objective and systematic analysis.
CLINICAL RESEARCH: Working with human subjects to
answer questions relevant to their well-being.
What is a research?

Objective of research
1. To discover new facts
2. To verify and test important facts
3. To analyse an event or process or phenomenon to identify the cause and
effect relationship
4. To develop new scientific tools, concepts and theories to understand and
solve various problems

Research methods vs methodology
Various procedures, schemes and algorithms used by a researcher during a
research study are termed as research methods. They are essentially
planned, scientific and value-neutral.
The procedures by which researchers go about their work of describing,
explaining and predicting phenomena are called research methodology. Its
aim is to give the plan of research.

Why knowledge about research is
important?
● Many clinicians in practise report that they feel unqualified to read the
medical literature critically.
● Scientific illiteracy is a major failing of medical education currently. (Lancet
2007)

Steps in research
1. Research Problem
2. Literature Review
3. Conceptual & Theoretical Frameworks
4. Research question and hypothesis
5. Framing specific objectives
6. Defining study population
7. Defining end points/ outcome variables
8. Data Collection (Research Performa)
9. Data Management and Analysis
10. Results
11. Implication of results
12. Publication of results

Hypothesis and thesis
● Thesis is the position that you believe represents truth.
● Hypothesis is the foundation on which you build your thesis. It is
the tentative construct to be proved or disapproved according to
evidence.
● Good hypothesis:
✔ Testable
✔ Convey the nature of the relationship being tested
✔ State exactly what variables form this relationship
✔ Reflect all variables of interest

Research question
● It is the fundamental core of a research project, study or review of literature.
● It focuses the study, determines the methodology and guides all stages of inquiry,
analysis and reporting.
● A good research question must be clear, feasible, significant and ethical.
● Characteristics of a Good Research Question:
1. Clear
2. Feasible
3. Significant
4. Ethical
5. Relevant

Developing research question
PICO FINER
● P – Population
● I – Intervention
● C – Control
● O – Outcome
● S- Study design
● F – Feasibility
● I - Interesting
● N – Novel
● E – Ethical
● R – Relevant

1. Descriptive questions
2. Analytical questions
Two categories of research questions

First draft of protocol
• Thought as it is written
• Keeps concept paper as summary
Uses the concept paper outline:
• Background/justification
• Objectives
• Methods
• Expected benefits
• Budget
Does not exceed 2000 words
• Introduction < 20% of length
Contains 5–10 key references

The Equator Network
(equator-network.org)
STROBE
CONSORT
SPIRIT
Prisma

Review of literature
● A “review of the literature” is a classification and evaluation of what
scholars and researchers have written on a topic.
● A literature review consists of an overview, a summary, and an evaluation
(“critique”) of the current state of knowledge about a specific area of
research.
● Helps in:
1. Enlarging knowledge about the topic
2. Information seeking
3. Critical appraisal

Descriptive and Analytical studies
1. Descriptive Studies:
• Objective: Estimating a quantity (e.g., prevalence, incidence).
• Example: Estimate the prevalence of physical activity.
2. Analytical Studies:
• Objective: Testing a hypothesis to determine relationships or
cause-and-effect.
• Example: Determine whether exercise reduces blood sugar
levels.

● A descriptive study describes the general characteristics of the distribution
of a disease or a health condition in relation to person, place or time.
● Uses information : easily available such as clinical record from hospitals,
census data and vital statistics.
● USES:
● allocate resources efficiently
▪ Useful in developing effective prevention and education programs
▪ formulating hypothesis
Descriptive
Pentad Who has the
disease
in question?
Age , sex, race,
occupation
What is the
condition or
disease being
studied?
Clear, specific ,
measurable
case definition
When is the
condition
common or rare?
Why did the condition
or disease arise?
Clues about cause
Where does or does not
the
disease or condition
arise?
The implicit sixth ‘’W’’ For ‘’so what’’ relates to public health

Types of descriptive studies
CASE REPORTS
▪ In this, an observant reports an unusual disease or association which prompts
further investigation with more rigorous study designs.

CASE SERIES REPORT
Aggregates individual cases in one report

CROSSECTIONAL STUDIES
● Provide a snap-shot of the population in a given time.
● Both exposure and outcome ascertained at same time.
● Less cost and lost to follow-up is not a problem.
● Temporal sequence : Not possible

SURVEILLANCE
● On going systematic collection, analysis and interpretation of health data
essential to the planning, implementation and evaluation of public health
practice.
● Active or passive.
● Feedback is key feature
Examples of Surveillance Systems:
• Integrated Disease Surveillance Program (IDSP) in India.
• Centers for Disease Control and Prevention (CDC) systems in the US.
• World Health Organization (WHO) global health observatories.

ECOLOGICAL
CORRELATIONAL STUDY
They look for association
between exposures and
outcomes in population rather
than in individuals.
The measure is correlation
coefficient r indicates how
linear is the relationship
between exposure and
outcome.

Critical appraisal of a observational study
● The STROBE (Strengthening Protocol items:
Recommendation for Interventional trials)
statement includes a list of 22 items that should
be included in reports of observational studies.

Cohort Studies - Marching towards outcome
A cohort study tracks two or more groups forward from exposure to
outcome
Types of cohort studies
● Prospective study
● Retrospective cohort study
● Ambi-directional cohort study

Advantages of cohort studies
Ascertains incidence and natural
history of disease.
Gives temporal sequence
Can investigate multiple
outcomes from single exposure.
Useful in study of rare exposures.
Disadvantages
Selection bias
Not optimum for rare diseases
Selection of study population
• General population cohorts or a
sub-set
• Framingham heart study
• Nurses health study
• Special exposure cohorts
• Occupational groups

Case Control Studies: Research in reverse
Useful for studying rare diseases
or diseases with a long latency
period.
Provides an estimate of the
association (e.g., odds ratio)
between exposure and outcome.
The study looks backward in
time to determine whether
exposure is more common in
cases compared to controls.
Elements of case control study
1. Selection of cases
2. Selection of controls
3. Information on exposure
4. Analysis

Strengths
• Good for examining rare
outcomes or outcomes
with long latency
• Relatively quick to
conduct, inexpensive
• Requires comparatively
few subjects
• Multiple exposures or
risk factors can be
examined
Weaknesses
• Susceptible to recall bias
• Selection of an
appropriate comparison
group may be difficult
• Rates of disease in
exposed and unexposed
individuals cannot be
determined

MATCHING:
Selecting patients so that the potential
confounders are equally distributed .
Eg, if age and gender are confounders, then foreach
patient of a certain age and gender in the diseased
group, a patient of same age and gender is selected in
the control group.

Scenario of clinical trials in India
The clinical trial industry rapidly
expanded in the first decade
of 21st century, but has faced some
challenges due to
regulatory reforms in 2012-13
The main challenges perceived by
international investigators
and sponsors include
• Delayed approval
• Quality of ethics review
• Shipment of samples: import and
export
• Overall deficiency of duly trained
investigators and centers
• Clause of compensation even for
clinical trial participants
• Recent requirement of audio visual
recording of consent process for
IND [investigational new drug] trials,
only in specified situations

population could be an entire
universe, whereas a sample could
be as selected a
small regions.
Sampling

the methods used in probability sampling
1.. Simple Random
Sampling:
2. Systematic
Sampling:
3. Stratified
Sampling:
4. Cluster Sampling:
5. Multistage Sampling:

Why do we need to calculate sample size?
1. Desired values for the probabilities of α (alpha) and β (beta).
2. The proportion of the baseline (controls or non-exposed) population:
• Exposed (for case-control studies)
• Diseased (for cohort/intervention studies)
• Often based on previous studies or reports
3. Magnitude of the expected effect (e.g., relative risk (RR) or odds ratio (OR)):
• Often based on previous studies or reports
• Minimum effect that the investigator considers worth detecting
4. Formula selection depends on:
• Study design
• Research question
• Type of data

Randomisation
● Process of assigning study participants to experimental and control
groups at random such that each has an equal probability of being
assigned to any group.
● Eliminate selection bias and balance known and unknown confounding
factors.

Randomised Controlled trials
● A type of study in which participants are randomly assigned
to one of two or more clinical interventions.
● Most scientifically rigorous method
● Gold standard for evaluating effectiveness of interventions.

Allocation concealment
● Technique to prevent selection bias by concealing the allocation sequence from
those assigning participants to intervention group.
● It prevents researchers from influencing which participants are assigned to which
group.
● For example: sealing each individual assignment in an opaque envelope.

Blinding
Refers to the practise of preventing study participants, health care
professionals, and those collecting and analysing data from knowing
who is in the experimental group and who is in the control group, in
order to avoid them being influenced by such knowledge.
● Single blind
● Double blind
● Triple blind

Intention to treat analysis
● Some participants may not complete the study or may deviate from the
intended protocol because of misdiagnosis, non-compliance, or withdrawal.
● To reduce this bias, results should be analysed on an ‘‘intention to treat’’
basis.
● Intention to treat analysis is a strategy in the conduct and analysis of
RCT’s that ensures that all patients allocated to either groups are analysed
together as representing that treatment arm whether or not they received the
prescribed treatment or completed the study.

Advantages and Disadvantages of Randomized Controlled
Trials (RCTs):
Advantages:
• Effective in controlling selection bias.
• Controls confounding bias without adjustments.
• Facilitates effective blinding.
• Retains cohort study benefits.
Disadvantages:
• Complex and expensive.
• May lack generalizability due to volunteer differences.
• Ethical challenges can be significant

CRITICAL APPRAISAL OF RCT
● Recent methodological analyses indicate that inadequate
reporting and design are associated with biased estimates of
treatment effects.
● Such systematic error is seriously damaging to RCTs.
● A group of scientists and editors developed the CONSORT
(Consolidated Standards of Reporting Trials) statement to
improve the quality of reporting of RCTs. It was first published
in 1996 and updated in 2001.
● The CONSORT statement comprises a checklist of essential
items that should be included in reports of RCTs and a
diagram for documenting the flow of participants through a
trial.

Systematic reviews
● a detailed and comprehensive plan and
search strategy with the goal of reducing
bias by identifying, appraising, and
synthesizing all relevant studies on a
particular topic.
● They are needed to establish clinical and
cost effectiveness of an intervention or
drug, if an intervention or activity is
feasible, if it is appropriate (ethically or
culturally) or if it relates to evidence of
experiences, values, thoughts or beliefs of
clients and their relatives.
• Clear, unambiguous,
structured questions
STEP 1:
Framing
questions for
the review
STEP 2:
Identifying
relevant
work
STEP 3:
Assessing
the quality of
study
• Extensive research without
language restrictions
STEP 4 :
Summarizing
the evidence
• Study assessment using
general critical appraisal
guides and design- based
quality checklist
STEP 5:
Interpreting
the findings
•Tabulation of study
quality & effect

Some Useful websites for systematic
reviews
● The Cochrane Library www.cochrane.org
● PubMed Clinical Queries: Find
Systematic Reviews
www.ncbi.nlm.nih.gov/entrez/query/static
/clinical.shtml
● The Joanna Briggs Institute
www.joannabriggs.edu.au/pubs/systemat
ic_reviews.php
● The Campbell Collaboration
www.campbellcollaboration.org
● The Centre for Evidence-Based
Medicine www.cebm.net
● The NHS Centre for Reviews and
Dissemination www.york.ac.uk/inst/crd
PRISMA statement recommends that a full
electronic search strategy for at least 1
major database should be given.

Meta-analysis
● “The statistical analysis of a large collection of analysis results from
individual studies for the purpose of integrating the findings”
● It is a quantitative, formal, epidemiological study design used to
systematically assess previous research studies to derive conclusions about
that body of research.

CRITICAL APPRAISAL OF SYSTEMATIC REVIEWS AND META-
ANALYSIS
(PRISMA- Preferred reporting items for systematic reviews and
meta-analysis)

Making of protocol for clinical trials
● SPIRIT 2013 ( Standard protocol items: Recommendations for
Intervention trials) Checklist enlists Recommended items to be
addressed in a clinical trial protocol & related documents

1. Precise operational
definitions of variables
2. Detailed
measurement protocols
3. Repeated
measurements on key variables
4. Training,
certification, and re-certification
5. Data audits
(of interviewers, of data centers)
6. Data
cleaning – visual, computer
7. Re-running
all analyses prior to publication
Dealing with
information bias

Effect Modifier
Effect Modifier:
• Alters the strength or direction of the
association between exposure and outcome.
• Works through interaction and is assessed
via stratified analysis.
• Example: Smoking intensifies the link
between asbestos exposure and lung cancer.

Some
Frequently Used
Statistical Terms

Types of Data:
Qualitative Data:
• Nominal: No specific
order (e.g., color of eyes)
• Ordinal: Ordered data
(e.g., stages of disease)
Quantitative Data:
• Discrete: Countable
values (e.g., family size, number of
siblings)
• Continuous:
Measurable values (e.g., height, weight)
Data is not information.summarise
data
• Average:
• Mean
• Median
• Mode
Dispersion
• Is it
enough to know the
average?
• Example
of swimming pool
• Measures
of variability:
• Range
• Inter-
quartile range
• Mean
deviation from mean
• Variance /
Standard deviation

CONFIDENCE INTERVAL
1. Definition:
• Provides an
estimated range of values likely
to include an unknown
population parameter.
2. Common
Confidence Levels:
• Typically 90%,
95%, or 99%
3. A 95% CI implies
that if the study were repeated
multiple times, 95% of the
calculated intervals would
contain the true population
parameter.
4. The area under the
normal curve within the CI
corresponds to the chosen
confidence level

NULL HYPOTHESIS
✔ It is a statistical concept
✔ The null hypothesis states that there is no association between the predictor and
outcome variables in the population.
✔ The proposition that there is an association is called the alternative hypothesis.
● TYPE I & TYPE II ERRORS
✔ A type I error (false-positive) occurs if an investigator
rejects a null hypothesis that is actually true in the
population; a type II error (false-negative) occurs if the
investigator fails to reject a null hypothesis that is
actually false in the population.
Common Ranges:
• Alpha (α):
0.01 to 0.10
• Beta (β):

● When the data are analyzed, such tests
determine the P value, the probability of
obtaining the study results by chance if
the null hypothesis is true.
● The null hypothesis is rejected in favour of
the alternative hypothesis if the P value is
less than alpha, the predetermined level of
statistical significance.
● “Non significant” results — those with P
value greater than alpha — do not imply
that there is no association in the
population; they only mean that the
association observed in the sample is
small compared with what could have
occurred by chance alone.
P-VALUE

Hazard ratio
A hazard ratio (HR) is a measure of the relative
risk of an event occurring at any point in time in
one group compared to another group in survival
analysis.
• HR = 1: No difference in risk
between the two groups.
• HR < 1: The event (e.g., death,
recurrence) is less likely to occur in the treatment
or exposed group compared to the reference
group.
• HR > 1: The event is more
likely to occur in the treatment or exposed group
compared to the reference group.

Pearson’s correlation coefficient
● Correlation is a technique for investigating the
relationship between two quantitative, continuous
variables, for example, age and blood pressure.
● Pearson's correlation coefficient (r) is a measure of the
strength of the association between the two variables.

Univariate and multivariate analysis
Univariate focuses on
individual associations,
while multivariate
accounts for multiple
factors and interactions,
providing a more
comprehensive
understanding of
outcomes.

Fabrication/falsification/plagiarism/authorship
● Fabrication: Creating
data/results that were not
derived from the study.
● Falsification: Manipulating
existing data/results to
misrepresent the findings.
● Plagiarism : Using
someone else’s published
or unpublished work, ideas,
or manuscript without
proper consent, credit, or
acknowledgment.
criteria for authorship:
1. Substantial
Contributions: Involves conception or design
of the work, or acquisition, analysis, or
interpretation of data.
2. Drafting or Revising:
Requires drafting the manuscript or revising
it critically for significant intellectual content.
3. Final Approval: Authors
must approve the final version for
publication.
4. Accountability: Authors
agree to be accountable for all aspects of
the work, ensuring accuracy, integrity, and
resolution of questions related to the work.

challenges in designing and implementing research studies
1. Random Error:
• Represents incorrect results due to chance and unknown sources of
variation.
• Can affect findings in either direction (overestimation or
underestimation).
• Minimization: Achieved by increasing the sample size and improving
precision in measurements or data collection.
2. Systematic Error:
• Indicates incorrect results due to bias, leading to consistent
distortion in one direction.
• Minimization: Requires improving the study design to reduce or
eliminate biases (e.g., selection bias, measurement bias).

KEY POINTS
● Clear Objectives
● Appropriate Design: Choose suitable
designs (e.g., RCTs, cohort, case-
control).
● Minimize Bias: randomization,
blinding, and proper controls.
● Control Confounders: Address
confounders
● Ethical Consideration:
● Accurate Data Collection:
● Proper Analysis:
● Transparency:

RESEARCH METHODOLOGY by DR SURBHI NARAYAN

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