Research design
is a systematic plan to study a scientific problem. The design of a study defines the
study type (descriptive, correlational, semi-experimental, experimental)
1. Experimental design:
In an experimental design, the researcher actively tries to change the situation,
circumstances, or experience of participants (manipulation), which may lead to a
change in behavior or outcomes for the participants of the study.
The researcher randomly assigns participants to different conditions, measures the
variables of interest and tries to control for confounding variables. Therefore,
experiments are often highly fixed even before the data collection starts.
In a good experimental design, a few things are of great importance. First of all, it is
necessary to think of the best way to operationalize the variables that will be
measured. Therefore, it is important to consider how the variable(s) will be measured,
as well as which methods would be most appropriate to answer the research question.
In addition, the statistical analysis has to be taken into account.
Thus, the researcher should consider what the expectations of the study are as well as
how to analyse this outcome. Finally, in an experimental design the researcher must
think of the practical limitations including the availability of participants as well as
how representative the participants are to the target population. It is important to
consider each of these factors before beginning the experiment.
Experimentation is also used to test existing theories or new hypotheses in order to
support them or disprove them.
This type of study can be described as follows:
Treatment group
R
O1
Control group
R
O1
X
O2
O2
R= Randomization
O= Observation or measurement
X= treatment or intervention(counseling on birth spacing)
Non-experimental research designs
Non-experimental research designs do not involve a manipulation of the situation,
circumstances or experience of the participants. Non-experimental research designs
can be broadly classified into three categories.
First, relational designs, in which a range of variables is measured.
These designs are also called correlational studies, because correlational data are most
often used in analysis.
Correlational designs are helpful in identifying the relation of one variable to another.
The second type is comparative research. These designs compare two or more groups
on one or more variable, such as the effect of gender on grades.
The third type of non-experimental research is a longitudinal design. A longitudinal
design examines variables such as performance exhibited(showed) by a group or
groups over time.
A quasi-experiment is an empirical(experimental) study used to estimate the causal
impact of an intervention on its target population. Quasi-experimental research shares
similarities with the traditional experimental design. but they specifically lack the
element of random assignment to treatment or control.
Treatment group
Control group
O1
O1
X
O2
O2
O= observation or measurement (staff morale questionnaire)
X= Treatment or intervention (Introduction of 10 hours day shift)
Survey
A field of applied statistics, survey methodology studies the sampling of individual
units from a population and the associated survey data collection techniques, such as
questionnaire construction and methods for improving the number and accuracy of
responses to surveys.
Statistical surveys are undertaken with a view towards making statistical inferences
(assumptions ) about the population being studied, and this depends strongly on the
survey questions used. Polls(survey) about public opinion, public health surveys,
market research surveys, government surveys and censuses are all examples of
quantitative research that use contemporary survey methodology to answer questions
about a population.
Although censuses do not include a "sample", they do include other aspects of survey
methodology, like questionnaires, interviewers, and non response follow-up
techniques. Surveys provide important information for all kinds of public information
and research fields, e.g., marketing research, psychology, health professionals and
sociology.