Readings and Overview
||Objective 2: Define the following terms,
which are relevant to the quantitative research process: Basic
research, applied research, rigor, and control.|
- Basic research (also called pure research and bench research)
is scientific investigation through empirical observations that can be
used to accumulate information or to formulate or refine a theory. This
means that findings from basic research are not directly useful to practice. A major focus of basic research
in nursing is to understand physiologic variables, their function, and
what factors affect their function. Many studies of a phenomenon over
many years may occur before the research is useful for practice.
- Applied research (practical research) is scientific investigation undertaken to solve a specific problem. Although the goal of applied research
is to find a solution to a problem, it may also be useful for adding to
a body of knowledge. In nursing, applied research is used to influence
or improve clinical practice, providing the groundwork for building an
EBP. Applied research may also be useful in theory testing and validating the theory's usefulness for clinical practice.
This may sound somewhat vague, but by using examples of questions from research on lipids you can see how they differ.
This an example of the type of question asked in basic research.
Are defects in the receptors on peripheral cell surfaces a possible
mechanism by which low-density lipoproteins are positively associated
with atherosclerosis? (Brown & Goldstein, 1986).
Here is an example of a question pertaining to lipids asked in applied research.
Will the daily use of a relaxation technique reduce total cholesterol, LDL, and triglycerides? (Carson, 1996).
Both questions seek to better understand lipid metabolism. However, the basic research question is focused at the cellular level, while the applied research question is focused at the behavioral level.
- Rigor is the application of discipline,
adherence to detail, and strict accuracy in the pursuit of excellence
in the conduct of research. A study conducted with rigor has a
tightly controlled study design (reducing the potential for bias),
precise tools for measuring the concepts of interest, and a
representative sample. In critiquing research, rigor is assessed by evaluating the reasoning and precision used in conducting the study.
- Control is the elements of the research design
that are applied to decrease the possibility that the research findings
are the result of error or bias. Control attempts to eliminate
any contamination from competing influences that might obscure the
relationship among the variables of interest-the independent and
dependent variables. Through control, possible influences and sources
of error or bias are held constant. When study control is
adequate, we have a reasonable assurance that the results accurately
reflect reality. Quantitative study designs evidence varying degrees of
control: Descriptive designs have little to no control, and experimental designs have multiple mechanisms that maintain control.
If you look back to Topic #1, you will see that quasi-experimental and
experimental designs both have the purpose of determining the
effectiveness of treatments. What differentiates the two types of
quantitative studies is the degree of control. Table 2-1 on
page 31 of Burns and Grove (2003) provides a good summary of the
differences in control by type of study and by type setting. The
researcher makes plans to control several potential sources of error in
the quantitative research design.
- Extraneous variables are variables that
confound or obscure the relationship between the independent and
dependent variables. Extraneous variables exist in all studies and must
be controlled through study design. The researcher can reduce the
number of extraneous variables by selection of study participants (sampling) or by selection of the setting or statistical procedures.
is the process of selecting a portion of the population to represent
the entire population. It is more practical and less costly to use a
sample to represent a population. However, the risk of error occurs if
the selected sample does not adequately reflect the behaviors, traits,
symptoms, beliefs, or life context of the population. How typical or
representative a sample is of the population on the key variables
indicates the quality of the sample. The following sampling procedures can be used to ensure a more representative sample. They vary widely in ease of use, cost, and time.
- Probability or random sampling
offers the greatest likelihood that the sample will be representative
of the population because every member of the population is selected
independently and has an equal chance of being selected. A random
sample strengthens the study.
or nonrandom samples increase the risk of bias or error because no
mechanism ensures that everyone in the population has an equal chance
of being selected. One mechanism researchers use to control extraneous variables in nonrandom samples is specifying inclusion and exclusion criteria. This ensures that subjects are similar on extraneous variables that may influence the results.
is one of the key distinctions between quasi-experimental and
experimental designs. A true experimental design must include random
sampling. Because research with human populations may make random
sampling difficult, both from a logistical and ethical perspective,
many nursing studies use convenience sampling, a form of nonrandom selection.
- Setting is the location in which a study is conducted.