2. LEARNING OBJECTIVES:
At end of the session the student will be able to
acquire adequate knowledge regarding quasi
experimental research design, develop positive attitude
and develop desirable skill in applying this research
design in the process of the nursing research.
SPECIFIC OBJECTIVE:
Define Research approach and design
Explain quasi-experimental research design
Explain the characteristics of the matching only quasi
experimental research design
Describe different types of quasi-experimental
research designs
List out the advantages of quasi experimental research
design
Evaluate the limitation of quasi experimental research
design.
3. INTRODUCTION
Nursing considered one of the oldest arts, yet finds
place among the youngest of professions.
Research is a systematic inquiry that uses disciplined
methods to answer questions or solve problems.
The ultimate goal of research is to develop, refine, and
expand a body of knowledge.
Nursing research is a systematic inquires designed to
develop knowledge about the issues of importance to
nurses, including nursing practice, education and
administration.
4. Research approach and research design are two
terms that are frequently used interchangeably
Research design basically provides an outline of
how the research will be carried out and the
methods that will be used
It includes the descriptions of the research
approaches, dependent and independent
variables, sampling design and a planned format
for data collection, analysis and presentation.
5. RESEARCH DESIGN
The research design is the master plan
specifying the methods and procedures for
collecting and analysing the needed
information in a research study
DEFINITION OF RESEARCH DESIGN
Research design can be defined as a
blueprint to conduct research studies, which
involve the description of research approach,
study setting, sampling size, sampling
technique, tools and method of data collection
and analysis to answer specific research
questions or for testing research hypotheses.
6. Thus the quasi experimental research came
into existence. Quasi-experimental design can
be more easily implemented in natural settings
and one can make direct assessment of
subjects, find out the effects of a specific
treatment introduced by the researcher, and
while doing so the researcher can also
minimize the influence of extraneous variables
7. TERMINOLOGIES
SL NO
TERMS USED IN BIOMEDICAL
RESEARCH
TERMS USED IN NURSING
RESEARCH
01
Randomized controlled trial True experimental research
design
02
Non-randomized controlled trial Quasi experimental research
design
03
Observational study design Non-experimental research
design
04
Case control study design Retrospective study design
05
Cross-sectional/ cross-sectional
descriptive study design
Descriptive study design
06
Case series -
07
Case report -
9. QUASI EXPERIMENTAL RESEARCH
DESIGN
• Quasi experimental research design
also called as non-randomized control.
• In other words, quasi experimental
designs have an element of
manipulation but lack the
randomization and sometimes even
the control group for comparison,
which are essential properties of the
RCTs.
10. • Quasi experimental designs are
generally used to establish the causality
(effect of independent variable on
dependent variable)
• In situations where researchers are not
able randomly assign the subjects to
groups or for various reasons in certain
situations cannot have a control group
for comparison in an experimental study
11. Design
• The first part of creating a quasi-experimental
design is to identify the variables.
• The quasi-independent variable will be the x-
variable,
• The predicted outcome is the dependent variable,
which is the y-variable.
• Once the variables have been identified and
defined, a procedure should then be implemented
and group differences should be examined
12. • Quasi-experiments are also effective
because they use the "pre-post testing".
• Quasi experiments have independent
variables that already exist such as age,
gender, eye colour.
• These variables can either be continuous
(age) or they can be categorical (gender). In
short, naturally occurring variables are
measured within quasi experiments.
13.
14. DEFINITION
Abraham & MacDonald (2011) state:"Quasi-
experimental research is similar to experimental
research in that there is manipulation of an
independent variable. It differs from experimental
research because either there is no control group,
no random selection, no random assignment,
and/or no active manipulation."
15. According to Mcburney & White (2007) ‘quasi
experiment is a research procedure in which the
scientist must select subjects for different
conditions from pre-existing groups’.
According to Broota (1989) “All such
experimental situations in which the experimenter
does not have full control over the assignment of
experimental units randomly to the treatment
conditions or the treatment cannot be manipulated
are called quasi experimental design.”
16. MAIN CHARACTERISTICS
Manipulation of the independent
variables to observe the effects on the
dependent variables
Lacks randomization of participants to
experimental groups,
Quasi independent variables are used
instead of true independent variables
where independent variables are not
manipulated in a completely controlled
situation.
17. TYPES OF QUASI
EXPERIMENTAL DESIGNS
Quasi experimental designs may be several types,
1. NON RANDOMIZED CONTROL GROUP DESIGN
2. NON EQUVALENT CONTROL GROUP POST TEST
ONLY DESIGN
3. TIME SERIES NON EQUVALENT CONTROL
GROUP DESIGN
4. TIME SERIES DESIGN
5. TIME SERIES DESIGN WITH WITHDRAWN AND
REINSTITUTION TREATMENT DESIGN
6. ONE GROUP PRETEST POST TEST DESIGN
18.
19. .
For example, a quasi experimental study was
planned to assess the effect of older people’s
involvement in social services on their
loneliness among elderly residing in selected
old age homes in New Delhi.
20. NON EQUVALENT CONTROL GROUP POST TEST ONLY
DESIGN
EXPERIMENTAL
GROUP TREATMENT POST-TEST
EXPERIMENTAL GROUP POST-TEST
21.
22.
23. For example a study is carried out to assess the
effect of VAP prevention bundle on VAP related
morbidity and mortality among critically ill
patients admitted on selected ICUs of a tertiary
care hospital.
24.
25. TIME SERIES DESIGN
• Experimental group
EXPERIMENTAL GROUP
O1
O2 O3
O4O5 TREATMENTO6
26. For example a researcher may evaluate pain
level of a group of patient having lower back
pain. After assessing of pain as long as 3
weeks participants are educated about special
exercises to manage the pain. Then weekly
pain level would be evaluated for next 3 weeks.
27. TIME SERIES DESIGN WITH WITHDRAWN AND
REINSTITUTION TREATMENT DESIGN
EXPERIMENT
AL GROUP
O1 O2
O6 O5
O3 O4
O8 O7
TREATM
ENT
Rein
stitu
te
Withd
rawn
28. ONE GROUP PRETEST POST TEST DESIGN
.
EXPERIME
NTAL
GROUP
PRE-
TEST
Treatment
Post-test
29. For example a study on the effect of
interventions on the stress coping resources of
associate degree nursing students. In this study
a pretest and post test design was used to
examine three groups in nursing programme.
Each group completed the instrument coping
resources inventory for stress CRIS at the
beginning at the end of the first year of nursing
course.
30. The modified curriculum group received
interventions for the development of stress coping
resources in their initial nursing course the
second group experienced self directed
interventions for the first year degree nursing
students
resulted concluded that curriculum intervention
for first year degree nursing students resulted in a
measures increase of stress monitoring and
31. Quasi experimental designs are more frequently used
This design is more suitable for real world natural setting
than true experimental research designs.
It allows researchers to evaluate the impact of quasi
independent variables under naturally occurring
conditions.
It may able to establish casual relationship relationship
wherein some of the hypotheses are practically
answered through this design only.
32. It is considered as a weak experimental design is
poor control over confounding variables which
could negatively affect the study results.
There is no control over extraneous variables
influencing the dependent variables
The absence of a control group or a lack of control
over the research setting makes the results of this
design less reliable and weak
33. Quasi-experimental research involves the
manipulation of an independent variable without
the random assignment of participants to
conditions or orders of conditions. Among the
important types are nonequivalent groups
designs, pretest-posttest, and interrupted time-
series designs.
34. Quasi-experimental research eliminates the
directionality problem because it involves the
manipulation of the independent variable. It does
not eliminate the problem of confounding variables,
however, because it does not involve random
assignment to conditions. For these reasons,
quasi-experimental research is generally higher in
internal validity than correlational studies but lower
than true experiments
