Page 464 - Encyclopedia of Nursing Research

QuANTITATIvE RESEARcH n 431

scales are used, quantitative summaries of techniques are used to test whether there
the data collected consist of aggregating the are significant relationships among study
number of responses in each scale category, variables that are delineated in the hypoth- Q
converting them to relative frequencies such eses, meaning relationships that cannot
as percentages, and if hypotheses are being be explained by random sampling error
tested in the research, applying one of many (chance). Widely used statistical techniques
nonparametric techniques available to test to test hypotheses include parametric tests
the statistical significance of the data. such as the t test and analysis of variance
continuous scales have continuous and nonparametric tests such as chi-square
quantitative values rather than verbal catego- test and rank–order correlation.
ries, as in nominal and ordinal scales. These Quantification in nursing research has
include the scientific measuring instruments helped advance nursing as a scientific disci-
widely used in nursing to measure variables pline. Quantification offers many advantages
such as temperature, weight, height, and to nursing research. There is a rich set of sta-
blood pressure. continuous measurement tistical tools available for data analysis that
scales have certain advantages over other can be applied to practically every research
scales because they yield more precise and question to assist in summarizing the data
sensitive data. Also, the statistical signifi- and evaluating their statistical significance.
cance of continuous data can be analyzed by The internal and external validity of the data
the more powerful parametric techniques. of quantitative research can be readily veri-
Quantitative research is concerned with fied by other researchers. Results of similar
making generalizations from a study sam- quantitative studies can be synthesized and
ple to a target population, a process called analyzed by the meta-analysis technique to
statistical inference. There are two categories shed new light on the research questions.
of generalizations in quantitative research: Dissemination of the results of quantita-
(a) estimates of the quantitative value of tive research is facilitated by the clarity and
selected characteristics of a target popu- objectivity possessed by quantitative data.
lation and (b) results of tests of statistical Some studies in nursing tend to over-
hypotheses concerning relationships among quantify. Reports of these studies are dom-
variables in the target population. Studies in inated by statistical data and tests, with a
the first category are called descriptive stud- minimum of narrative discussion, providing
ies; those in the second category are called little interpretation of the clinical significance
analytical or explanatory studies. The focus of of results. Sometimes, too little time is spent
many early nursing studies was to describe on evaluation of the quality of data used or
nurses and nursing practice using question- on the appropriateness of the statistical tests.
naire or interview techniques to collect data Qualitative research, with its focus on mean-
from large samples of respondents. Recent ing and interpretation of data, can help to
studies using conceptual frameworks from enrich the results of quantitative studies in
emerging nursing theories and models have nursing. The approach called triangulation,
tested hypotheses in controlled or semicon- which utilizes and integrates methodology
trolled settings. from quantitative and qualitative research in
Statistical techniques are used exten- a single study, can help achieve the best of
sively in descriptive studies to compute sum- both worlds of research methodology.
mary measures, such as means, standard The history of nursing research reveals
deviations, and coefficients of correlation, a trend from purely descriptive studies of
and to determine the sampling error of the nurses and nursing to the evaluation of the
measures. In explanatory studies, statistical effects of nursing care. Properly applied