Chapter 2
Introduction to the Quantitative
Research Process
Copyright © 2011 by Saunders, an imprint of Elsevier Inc.
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Quantitative Research
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Formal, objective, rigorous, systematic
process for generating information
Describes new situations, events, or
concepts
Examines relationships among variables
Determines the effectiveness of treatments
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Quantitative Research (cont’d)
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Descriptive
Correlational
Quasi-experimental
Experimental
Increased
control
with type
of study
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Descriptive Research
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Exploration and description of phenomena in
real-life situations
New meaning is discovered and the
description of concepts is accomplished
Helps to identify relationships
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Correlational Research
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Looks at the relationship between two or
more variables
Determines the strength and type of
relationships
Explains what is seen
No cause and effect
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Quasi-experimental Research
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Examines cause-and-effect relationships
Less control by researcher than true
experimental designs
Samples are not randomly selected.
All variables in the study cannot be controlled
by the researcher.
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Experimental Research
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Looks at cause-and-effect relationships
Highly controlled, objective, systematic
studies
Involves the measurement of independent
and dependent variables
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Experimental Research (cont’d)
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Main characteristics:
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Controlled manipulation of at least one
independent variable
Uses experimental and control groups
Random assignment of the sample to the
experimental and control groups
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Concepts Relevant to Quantitative
Research
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Basic research
Applied research
Rigor
Control
Extraneous variables
Sampling
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Basic Research
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Research for the sake of research
Research to find out the truth
Investigating “what is”
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Applied Research
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Attempts to solve real problems in clinical
practice
Concerns what effects the intervention may
have on patients
Applies findings in the real world on real
patients
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Rigor in Quantitative Research
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Striving for excellence in research and
adherence to detail
Precise measurement tools, a representative
sample, and a tightly controlled study design
Logical reasoning is essential.
Precision, accuracy, detail, and order required
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Control in Quantitative Research
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Rules are followed to decrease the possibility
of error, and are the design of the study.
Different levels of control depending on study
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Quasi-experimental studies partially controlled
regarding selection of subjects
Experimental studies highly controlled because of
precision of sample selection
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Extraneous Variables in
Quantitative Research
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These occur in all research studies.
They may interfere with the hypothesized
relationships between variables.
The influence of extraneous variables can be
decreased through sample selection and the
use of defined research settings.
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Sampling in Quantitative Research
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Process of selecting subjects who are
representative of the population
Random sampling
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Each member has an equal chance of being
selected.
Has the most control
Convenience sampling
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Whoever is available
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Settings in Quantitative Research
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The location where studies take place
Must be defined in advance
Involved in the rigor and control of the study
Types of research settings:
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Natural or field settings
Partially controlled settings
Highly controlled or laboratory settings
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Control in Quantitative Research
Type of
Quantitative
Research
Researcher
Control
Research
Setting
Descriptive
Uncontrolled
Natural or partially
controlled
Correlational
Uncontrolled or
partially controlled
Natural or partially
controlled
Quasi-experimental
Partially controlled
Partially controlled
Experimental
Highly controlled
Laboratory
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Problem-Solving Process
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Data collection
Problem definition
Plan
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Setting goals
Identifying solutions
Implementation
Evaluation and revision
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Steps of the Quantitative Research
Process
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Research problem and purpose
Literature review
Study framework
Objectives, questions, or hypotheses
Study variables
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Steps of the Quantitative Research
Process (cont’d)
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Assumptions
Limitations
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Methodological
Theoretical
Research design
Population and sample
Methods of measurement
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Steps of the Quantitative Research
Process (cont’d)
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Data collection and analysis
Research outcomes
Communication of findings
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Research Problem and Purpose
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Research problem is an area of concern
needing research for nursing practice.
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The problem identifies, describes, or predicts the
research situation.
Research purpose comes from the problem
and identifies the specific goal or aim of the
study.
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The purpose includes variables, population, and
setting for the study.
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Literature Review
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Collecting pertinent literature to give in-depth
knowledge about the problem
Understanding what knowledge exists to
make changes in practice
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Study Framework
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Framework is the abstract, theoretical basis
for a study that enables the researcher to link
the findings to nursing’s body of knowledge.
Theory is an integrated set of defined
concepts and relational statements that
present a view of a phenomenon and can be
used to describe, explain, predict, or control
phenomena.
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Research Objectives, Questions, and
Hypotheses
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All identify relationship between variables and
indicate population to be studied
Narrower in focus than the purpose and often
specify only one or two research variables
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Study Variables
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Variables are concepts that are measured,
manipulated, or controlled in a study.
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Concrete variables: temperature, weight
Abstract variables: creativity, empathy
Conceptual definition: gives meaning to a
concept
Operational definition: variable can be
measured using this description
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Example of Definitions: Physical
Symptoms
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Conceptual definition
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Physical symptoms are “behavioral manifestations
that result directly from the traumagenic dynamics
of child sexual abuse.”
(Hulme & Grove, 1994, p. 522)
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Operational definition
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ASI questionnaire was used to measure physical
symptoms
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Assumptions
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Statements are taken for granted or are
considered true.
Assumptions are often unrecognized in
thinking and behavior.
Sources of assumptions are universally
accepted truths.
They are often embedded in the philosophical
base of the study’s framework.
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Limitations
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Restrictions in a study that may decrease the
credibility and generalizability of the findings
Theoretical limitations
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Restrict the generalization of the findings
Reflected in the framework and definitions
Methodological limitations
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Restrict the population to which the findings can
be generalized
 May result from an unrepresentative sample or
weak design
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Research Design
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Blueprint for conducting the study
Maximizes control over factors that could
interfere with the study’s desired outcome
Directs the selection of the population,
sampling, methods of measure, plans for data
collection, and analysis
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Population and Sample
Population
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Sample
All elements that meet
certain criteria for
inclusion in study
Example: all women
students in higher
education
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A subset of the
population that is
selected for study
Example: women
students in three state
universities in the
Southwest
(Hulme & Grove, 1994)
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Methods of Measurement
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Assigning numbers to objects
Application of rules to development of a
measurement device or instrument
Data are gathered at the nominal, ordinal,
interval, or ratio level of measurement.
Must examine reliability and validity of
measurement tool
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Reliability: consistency of the tool
Validity: does it measure what it is supposed to
measure?
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Data Collection
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Precise, systematic gathering of information
for the study
Consent must be obtained from the sample.
Researchers use observation, interviews,
questionnaires, or scales to gather
information.
Described under the “procedures” section of
a research article
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Data Analysis
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Reduce, organize, and give meaning to data
Descriptive and inferential analysis of data
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Results
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Descriptions of findings after data were
analyzed
Usually organized by research objectives,
questions, or hypotheses
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Research Outcomes
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Interprets data findings in meaningful manner
Involves forming conclusions and considering
implications for nursing
Suggests future studies
Generalizes the findings
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Research Reports and
Communication of Findings
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Summarizes major elements of a study and
identifies contributions of study to nursing
knowledge
Presented at professional meetings and
conferences and published in journals and
books
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Content of Research Reports
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Abstract—summary of study in 100 to 250
words
Introduction—problem, purpose, literature,
framework, and hypothesis
Methods—design, sample, setting, tool
Results—data analysis procedures
Discussion—findings, conclusions,
implications
Reference list—all sources cited
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Skimming a Research Report
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Quickly review source for broad overview.
Read title, author’s name, abstract,
introduction, and discussion.
Examine conclusions and implications.
Give preliminary judgment of study.
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Comprehending a Research Report
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Type of study conducted—highlight key
points
Knowledge available on topic
Expertise of researcher
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Replication versus original research
Funding resources of researcher
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Amount of funding
Sources of funding
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Analyzing a Research Report
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Examine parts of report in depth for accuracy,
completeness, uniqueness of information,
and organization.
Was research process logically presented?
Examine discussion section for critical
arguments.
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Initial Research Report Critique
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What type of study was conducted?
What was the setting for the study?
Were steps for the research process clearly
identified?
Were any of steps missing?
Did the steps logically link together?
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