1.

UNIT-4
EPIDEMIOLOGY
Randomized Controlled Trials
Submitted To,
Dr. ANJALATCHI
M.Sc(N)MD(AM)MBA(HA)
ERA COLLEGE OF NURSING
SARFARAJ GANJ
LUCKNOW
Submitted By,
Mrs. MARY TEENA
M.Sc(N) I YEAR
ERA COLLEGE OF NURSING
SARFARAJ GANJ
LUCKNOW

2.

At the end of the topic the learner will be able to,
o Discuss about experimental epidemiology.
o Define Randomized Controlled Trials.
o Explain Randomized Controlled Trials.
o Design the Randomized Controlled Trial.
o Enlist the basic steps in conducting Randomized
Controlled Trial.
o List down the types of Randomized Controlled Trial.
Learning Objectives

3.

 Random = Governed by chance
 Randomization = Allocation of individuals to groups by
chance
 (Each sampling unit has the same chance of selection

Variables = It refers to a person, place, thing or
phenomenon that you are trying to measure in some way.
Terminology

4.

 Independent: It is the characteristic of a psychology
experiment that is manipulated or changed by
research.
 Dependent: It is the variable that is being measured
or tested in an experiment.
 Field trial: It is a real life experiment which test
directly whether proposed interventions actually
works.
 Community trial: The studies with whole
community on experimental units.

5.

 Epidemiological experiment: It is the study of the
relationships of various factors, determining the
frequency and distribution of disease in a
community.
 Quantitative: It is research strategy that focuses on
quantifying the collection and analysis of data.
 Comparative: It is the act of comparing two or more
things.
 Controlled experiment: An independent variable
(the cause) is systematically manipulated and the
dependent variables (the effect) is measured.
 Protocol: It is the guide book for research study .

6.

 Manipulation : It refers to control over the
independent variables.
 Intervention: Strategy and process designed to
measure the change in a situation after a systematic
modification.
 Bias: It occurs when systemic error is introduced
into sampling or testing by selecting one outcome or
answer over others.
 Attrition: The loss of follow up due to death or
migration of an individual is called as attrition.

7.

 Blinding: It refers to a practice where study
participants are prevented from knowing certain
information that may somehow influence them.

8.

EXPERIMENTAL EPIDEMIOLOGY
RANDOMIZED CONTROLLED
TRIAL (RCT)

9.

Introduction:
 It is mainly in the last 35-40 years, determined efforts
have been made to use scientific techniques to
evaluate methods of treatment and prevention.
 It is really an epidemiologic experiment.
 It is widely regarded as gold standard for evaluating
health care technologies as it allows us to be
confident that a difference in outcome can be directly
attributed to a difference in the treatments and not
due to some other factor.
Randomized Controlled
Trials

10.

 Definition:
 Randomized Controlled Trials are quantitative,
comparative, controlled experiments in which
investigators study two or more receive them in
random order.
 The RCT is one of the simplest and powerful tools in
clinical research.

11.

 Drawing up a protocol
 Selecting reference and experimental population
 Randomization
 Manipulation and Intervention
 Follow-up
 Assessment of outcome
Basic steps in conducting a RCT

12.

 Strict protocol
 Aims and objectives
 Questions to be answered
 Criteria of selection
1. DRAWING UP A PROTOCOL

13.

 Reference or target population - population
to which the findings of the trial, if found
successful, are expected to be applicable (eg.
drugs, vaccines, etc.)
Experimental or study population - actual
population that participates in the
experimental study
2.Selecting reference and
experimental population

14.

 Procedure: Participants are allocated into study
and control groups
 Eliminates bias and allows comparability
 Both groups should be alike with regards to
certain variables that might affect the outcome of
the experiment
 Best done by using table of random numbers
3.Randomization

15.

 Deliberate application or withdrawal or reduction of
a suspected causal factor
 It creates an independent variable
4.Manipulation and
intervention

16.

 Implies examination of the experimental and
control group subjects
 -: at defined intervals of time,
 -: in a standard manner, with equal intensity,
under the same given circumstances.
5.Follow up

17.

 Positive results
 Negative results
 Biases: subject variation, observer bias, evaluation
bias
 Can be corrected by blinding
6.Assessment

18.

• Single
• (patient doesn’t know)
• Double
• (neither patient nor investigator knows)
• Triple
• (none of the patients, investigators or
analysts know)
Blinding masking

19.

Randomization is a key feature And heart of
RCT

20.

 The types of Randomized Controlled Trials:
 Clinical trials
 Preventive trials
 Risk factor trials
 Cessational experiment
 Trial of aetiological agents
 Evaluation of health services

21.

 Park’s text book of preventive and Social Medicine, Park.
K, 23rd edition, Bhanot, Page no: 88-97.
 Nursing Research statistics, Suresh K Sharma,
ELESEVIER, 3rd Edition Page No: 162.
 www.wikipedia.com
REFERENCES

22.
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THANK YOU