Research Design in Quantitative Study

Answer 1:
1. In case of research design for a quantitative study, it is necessary to review the research
question and objectives of research and interpret the research design that would fulfil the
study objective. The selection of research design is influenced by availability of
information, sufficiency of data, time availability, rigour in sample selection, technical
understandings of research and internal and external variables of research. This helps in
the review of proper qualitative factors that influence the search process (Patten &
Newhart, 2017).
Answer 2:
Experimental research design: It is a research method in which several manipulations and
controlled testing is done to evaluate the causal effect of an intervention. However, human error
is a threat to the validity of this research.
Quasi-experimental research design: It is a type of experimental research design, where
interventions are not randomly allocated to a group and other eligibility criteria is used to assign
participants to treatment and control group. The advantage of this research design is that it takes
less time and it eliminates ethical issues associated with random assignment of study
participants. However, this design lacks generalizability as it may lead to creation of non-
equivalent test groups because of random assignment.
Pre-experimental designs: In pre-experimental designs, only single group is observed regarding
effect of treatment instead of comparison between two groups. This is planned before
implementation of a true experiment and the main purpose is to see the effect before a true

experiment is implemented. However, this research design lacks validity (Patten & Newhart,
2017).
Non-experimental designs: It is a type of research design in which independent variables cannot
be manipulated and the study depends on the interpretation or observation to come to conclusion
of the study. Hence, cause and effect relationship cannot be explored through this type of
research design and the data for this research depends on case studies or surveys. The key
advantage of non-experimental design is that the findings can be generalized for the larger target
population group (Campbell & Stanley, 2015).
Answer 3
The difference between cross-sectional and longitudinal research design is that longitudinal
research is done with fresh sample of research participants, whereas cross-sectional research is
done with same sample at several point of time. The advantage of cross-sectional research design
is that it facilitates comparison of different variables at the same time. However, cause and effect
relationship cannot be explored. In contrast, longitudinal research designs give researchers the
advantage of interpreting trends or development related to change in characteristics of target
population group (Creswell & Creswell, 2017).
Answer 4
Extraneous variables are those variables that negatively affect the data collection process and
interfere with the validity of data. The methods that are used to control extraneous variables
include controlling differences between participants in terms of age, ability or other factors,
making research variables consistent throughout the research and controlling situational variables

in the place where the research needs to be carried out. Random allocation and blinding also
ensures that sample group are equally treated and any confounding factors are eliminated.
However, this is effective only in case of large sample size (Nielsen & Raswant, 2018).
Answer 5
In quantitative research designs, the factors that influence internal validity includes changes
in study subject over the course of experiment, lost to follow up cases and failure of research
participants to complete all phase of the research. Instrumentation related issues such as changes
in calibration of research tool or change in observer may threaten internal validity of research
(Edmonds & Kennedy, 2016).
Answer 6:
Emergent design is used in qualitative research to adapt to new ideas during qualitative
research. This helps to collect many unanticipated information and increase the richness of
research. Hence, this design helps to explore a research phenomenon in-depth.
The key features of a qualitative research design are as follows:
 The research focus on collection of descriptive details related to the research question
 It does not rely on specific tool for data collection. Researcher’s judgment determines the
method of data collection
 It involved subjective interpretation of events
 It is a time consuming process and it involves lack of generalizability of data.