Research Design
Andrea M. Landis, PhD, RN
UW LEAH – 2013
Learning Objectives
 Discuss concepts important to research design
 Identify different types of non-experimental, experimental,
and quasi-experimental research designs
 Review pertinent human subject issues related to adolescents
Research Design: Definition and
Characteristics
 The vehicle for hypothesis testing or answering research
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questions
A blueprint for conducting a study
Maximizes control over factors that could negatively effect
the validity of study findings
Guides the researcher in planning and conducting a study
Links the steps of the research process in the study
Concepts Important to Research
Design
 Causality
 Cause is not directly observable but must be observed
 The cause is necessary for the effect to occur
 Multicausality – recognition that a number of interrelating
variables can be involved in causing a particular effect
 Probability – Addresses the likelihood that something will happen
in a given situation
 Bias
 To slant away from the truth or the expected
 Failing to consider or include both sides of the question or hypothesis
 Control – A check or comparison. Methods to keep the study
conditions constant during the study
Forms of Control
 Manipulation – Researcher exercises by specifying the IV
 Elimination or Inclusion – Holding certain aspects of
intervening and extraneous variables constant
 Statistical – Controlling extraneous variables by including
them in the statistical analysis
 Randomization – Distribution of effects of extraneous
variables via change with assignment of subjects to groups
based on probability
 What is the difference between random sampling and random
assignment?
Concepts Important to Research
Design
 Study Validity – truth or accuracy of the study findings.
 Internal Validity – extent to which the effects detected in the
study are a true reflection of reality.
 External Validity – extent to which the findings of the study
can be generalized to the general population
Types of Research Designs
 Non-experimental – both randomization and manipulation
absent
 Experimental – both randomization and manipulation
present
 True or classic experiment
 Quasi-experimental – manipulation present, but not
randomization
 One-group (pretest – posttest) design
Major Categories of Non-experimental
Designs
 Descriptive
 Designed to document conditions, attitudes, or characteristics
of individuals or groups
 Exploratory
 Focuses on the relationships among these factors
 Predictive
 Aimed at the development of systems to predict criteria of
interest by utilizing information from one or more predictors
 Explanatory
 Aimed at testing of hypotheses formulated to explain
phenomena of interest. Involves theoretical model testing.
Methods of Non-Experimental
Research
 Retrospective (ex post facto)
 Involves examining data that have been collected in the past, often
obtained from medical records or survey
 Prospective
 Variables are measured through direct recording in the present
 Longitudinal
 Follows a cohort of subjects over time, performing repeated
measurements at prescribed intervals
 Cross-sectional
 Researcher studies a stratified group of subjects at one point in time
and draws conclusions about development within a population by
comparing the characteristics of those strata.
Perspectives in Qualitative Research
Designs
 Phenomenology
 Seeks to draw meaning of experiences through narrative subject
materials. Words like “lived experience” often describe
phenomenological studies.
 Ethnography
 Study of the social milieu of a specific cultural group or people.
Researcher often immersed in subject’s way of life.
 Grounded Theory
 Researcher uses data to develop a theory that will explain what
is observed. Researcher collects, codes, and analyzes data
simultaneously.
Epidemiological Research
 Concerned with the study of the distribution of disease,
injury, or dysfunction in human populations
 Observational Epidemiologic Studies
 Gather measures about disease frequency: prevalence (existing
cases), incidence (new cases)
 Analytic Epidemiologic – Used when enough is known about
a condition to allow testing of hypotheses about the
association of specific risk factors (exposures) and outcomes
 Case-control studies – groups of individuals are selected on the
basis of whether they have the disorder under study
 Cohort studies – group of individuals followed over time to
determine if they will develop a disorder
Nontraditional Designs: Examples
 Methodological Designs
 Used to develop research approaches or the R/V of instruments
to measure constructs used as variables in research
 Secondary Analysis
 Studying data previously collected in another study
 Meta-Analysis Designs
 Involves merging findings from many studies that have
examined the same phenomenon
Levels of Evidence
Challenges of Consenting
Adolescents
Andrea M. Landis, PhD, RN
Assistant Professor
UW School of Nursing
Assent vs. Informed Consent
 Assent: active affirmation of a desire to participate.
 Consent: must be voluntary and based upon adequate
knowledge of the purpose, risks, and potential benefits of a
research study.
 Individuals who do not have the authority to consent to
participate in research must still provide their assent.
 minors or
 physically or mentally incapable of making informed decisions
Why are teens vulnerable?
 Dramatic and relatively rapid biological changes, with a great deal
of individual variation;
 An evolving developmental and cognitive maturity;
 Feelings of lacking authority and control in healthcare settings; and
 Dependence on parents and healthcare providers to make informed
decisions about their care
What to keep in mind with this group?
 Maintain a balance between scientific responsibility and
participant welfare.
 Researchers must consider adolescents’ decision-making and
information-processing capacities.
 Differences may occur based upon:
 particular situation (e.g., chronic condition, prior experiences,
cognitive functioning and abilities)
 setting (e.g., hospital vs. community).
 Assessing the risk of coercion is important at any chronological
age, but especially important for adolescent participants.
 Being in research is your choice.You can say Yes or NO. Either way
is OK.
What is the age range for moving
from assent to consent?
 Assent provides:
 information in concrete, age-appropriate format
 terms that explain the purpose of the research, what the participant
will be asked to do, the procedures that will take place, and
 Identifies risks and benefits of participation.
 For children and adolescents 7–17 years of age.
 Many societies recognize age 18 as the age at which individuals are
recognized and treated as adults.
 Pubertal changes during adolescence are variable in both timing
and rate, and often not associated with chronological age.
What wording/language works best
to convey risks/benefits in this
group?
 To convey risks:
 You may get tired,…
 The activity monitor may rub like…
 You may feel embarrassed during…
 You do not have to answer any question you do not
want to
 To convey benefits:
 You may learn more about your….
 What we learn may help other kids….
What is the parent role in the
consenting process?
 Important things to remember:
 Obtaining an adolescent’s agreement to participate in a study should be
done separately from consent from parents.
 Adolescents should be allowed to read (or be read to) the assent form
in a room apart from their parents.
 Use age and developmentally appropriate strategies (larger font;
illustrated).
 Reassure the teen that the information they provide will be protected
and kept confidential (from parents).*
 Adults (consent) and adolescents (assent) should receive their own
copy.
 At subsequent data collection points and visits, the adolescent
should be given an opportunity to ask questions.
Any lessons learned from working with
this group?
 More than just signing forms.
 Adolescents need to be active participants in the decision
making process (e.g., assent/consent, knowledge of the risks
and benefits, etc.).
 Watch out for overt vs. subtle coercion.
 Your mom or dad said it is okay for you to participate…
 Great deal of individual variation, never assume.
How do you decide on study
compensations?
 Teen vs. parent
 Hourly vs. stages
 This totals $___ if you do all the parts of the study.
 “To thank you for being in this study…”
 Gift card vs. $$
 Other compensation