hypothesis

1. Course : Msc.Nursing
Subject : Nursing Research and Statistics
Unit : IV-Research Problem
Topic : Hypothesis and Variables
By
Dr.Prof.Mrs.N.Saraswathi, M.Sc (N)., Ph.D.,
Principal cum Professor,

2. OBJECTIVES
At the end of the lecture students are able to:
• define hypothesis.
• list down the advantages of hypothesis
• enumerate the Characteristics of good hypothesis
• enlist the sources of hypothesis.
• explain the types of hypothesis.
• test the hypothesis
• mention the Characteristics of hypothesis.
• define Variable.
• enumerate the types of Variable.

3. HYPOTHESIS

4. Definition
• Hypothesis is considered as an intelligent
guess or prediction, that gives directional to the
researcher to answer the research question.
• Hypothesis or Hypotheses are defined as the
formal statement of the tentative or expected
prediction or explanation of the relationship
between two or more variables in a specified
population

5. Cont…
• A hypothesis is a formal tentative statement of
the expected relationship between two or more
variables under study.
• A hypothesis helps to translate the research
problem and objective into a clear explanation or
prediction of the expected results or outcomes of
the study.

6. ADVANTAGES OF HYPOTHESIS
• It provides clarity to the research problem and
research objectives.
• It describes, explains or predicts the expected
results or outcome of the research.
• It indicates the type of research design.
• It directs the research study process.
• It identifies the population of the research study
that is to be investigated or examined.
•It facilitates data collection, data analysis and data
interpretation.

7. Count..
• Hypotheses provides link between theories & actual
practical research.
• It provides a bridge between theory & reality.
• A hypothesis suggests which type of research is likely to
be most appropriate.
• As it is a tentative statement of anticipated results, it
guides the researcher towards the direction in which the
research should proceed.
• It stimulates the thinking process of researcher as the
researcher forms the hypothesis by anticipating the
outcome.
• It also determines the most appropriate research
designs & techniques of data analysis.

8. CHARACERISTICS OF A GOOD
HYPOTHESIS
• Conceptual clarity:
Hypothesis should consist of clearly defined &
understandable concepts. It should be stated in very
terms, the meaning & implication of which cannot be
doubted. To facilitate the conceptual clarity, hypothesis
can be stated in declarative statement, in present
tense.
• Empirical referents:
Research must have an ultimate empirical referent. No
usable hypothesis can embody moral judgments. A
good hypothesis must have empirical basis from the
area of enquiry.

9. Count…
• Objectivity:
Hypothesis must be objective, which
facilitates objectivity in data collection & keeps the
research activity free from researcher value -
judgment.
• Specificity:
It should be specific, not general, & should
explain the expected relations between variables.
For example, regular yoga reduces stress.
• Relevant:
The hypothesis should be relevant to the
problem being studied as well as the objectives of
the study. Hypothesis must have relevance with

10. Count…
• Testability:
Hypothesis should be testable
& should not be a moral judgment. It must be
directly/indirectly observable & measurable..
• Consistency:
A hypothesis should be consistent
with an existing body of theories, research
findings, & other hypotheses. It should
correspond with existing knowledge.
• Simplicity:
A hypothesis should be formulated in
simple & understandable terms. It should
require fewer conditions & assumptions.

12. TYPES OF HYPOTHESIS
Simple & complex hypothesis
Associative & causal
hypothesis
Directional & nondirectional
hypothesis
Null & research hypothesis

13. SIMPLE & COMPLEX HYPOTHESIS
• Simple hypothesis:
 It is a statement which reflects the relationship between two
variables.
• Example: Smoking leads to cancer
• The higher ratio of unemployment leads to crimes.
• Complex hypothesis:
 It is a statement which reflects the relationship between
more than two variables.
• Example: Smoking and other drugs leads to cancer,
tension, chest infections etc.
– The higher ratio of unemployment poverty illiteracy
leads to crimes like dacoit etc.

14. ASSOCIATIVE & CAUSAL HYPOTHESIS
• Associative hypothesis:
 It reflects a relationship between variables that occurs or
exists in natural settings without manipulation.
 This hypothesis is used in correlational research studies.
 Eg. Communication skills of health care providers & cost
of care related to the satisfaction of patients. Predicts
relationship among variables but not the type of
relationship

15. Count…
• Causal hypothesis:
 It predicts the cause-and-effect relationship between
two or more dependent & independent variables in
experimental or interventional setting, where
independent variable is manipulated by research to
examine the effect on the dependent variable.
 For examples, prevalence of pin site infection is lower
in patients who receive pin site care with hydrogen
proxidide as compared to patients who receive the pin
site care with Betadine solution.

16. DIRECTIONAL & NONDIRECTIONAL
HYPOTHESIS
• Directional hypothesis:
 It specifies the expected direction of the relationship
between the independent & dependent variables.
 The directional terms are used to state the hypothesis such
as positive, negative, less, more, increased, decreased,
greater, higher, lower, etc.
• Example: High quality of nursing education will lead to high
quality of nursing practice skills.
• Girls ability of learning moral science is better than boys.

17. Count…
• Nondirectional Hypothesis:
 It reflects the relationship between two or more
variables, but is does not specify the anticipated
direction & nature of relationship such as positive or
negative.
• Example: teacher student relationship
influence student’s learning.
• There is no significant difference between 9th class
boys and girls abilities of learning moral values.

18. Null & research hypothesis:
• Null hypothesis (H0)/ statistical hypothesis
 It states that there is no relationship between the
independent & dependent variables.
 For example, ‘there is no relationship between
smoking & the incidence of coronary artery
disease’.
• Research hypothesis (H1):
 It states the existence of relationship between two
or more variables.
 For examples, ‘there is relationship between
smoking & incidence of lung cancer.

19. STEPS IN TESTING OF HYPOTHESIS
Formulating
hypothesis by
making relational
statements
Developing
research
problem &
objectives
Designing
a study
Conductin
g a study
Accept / reject/
modify
hypothesis
based on data

20. VARIABLES
• Meaning A variable is a concept or abstract idea that
can be described in measurable terms. In research,
this term refers to the measurable characteristics,
qualities, traits, or attributes of a particular
individual, object, or situation being studied.
• Definition variables are concepts at different level of
abstraction that are concisely defined to promote
their measurement or manipulation within study.
- chinn & kramer

21. TYPES OF VARIABLES
• Independent Variable also called the
manipulated variable
The condition that is intentionally changed by the
investigator in an experiment. There can be only
one independent variable in an experiment
• Dependent Variable also called the responding
variable
The factors or conditions that will change as a
result of the independent variable .The factors that
you measure or observe as data .There can be one
or more dependent variables in an experiment.

22. TYPES OF VARIABLES
• Research variables:
In descriptive, explorative, comparative & qualitative
research studies, variables are observed or measured in
natural setting as they exist, without manipulating or
imposing the effect of intervention or treatment.
• Demographic variables:
Characteristics & attributes of the study subjects are
considered as demographic variables.
• Controlled Variables
The factors or conditions that are kept the same (unchanged)
in an experiment. There are many controlled variables in an
experiment.

23. Identify variables for the following experiments.
Example: Does changing the color of light affect
the growth rate of plants?
• Independent Variable also called the manipulated
variable - color of light
• Dependent Variable also called the responding
variable - growth rate of plants.
• Controlled Variables - Same type / size of plant,
Same wattage of bulb,Same amount of water,
Same soil, Light on for the same amount of etc…

24. • Extraneous variables
– External variables are the factors that are not the part
of the study but may affect the measurement of the
study variables.
• Example: A study to assess the effect of two different pin
site care protocols on prevention of pin site infection
among patients with external skeletal fixation.
• pin site care protocols- independent variables
• pin site infection- dependent variables
• pin site infection may also be influenced by some other
factors , such as low Hb level or higher blood sugar level
among these patients. These extraneous variables may
be controlled by excluding the patients with anaemia or
diabetes.

25. BASED ON THE NUMBER OF VARIABLES UNDER STUDY
• Univariate study: If one variable under study.
• Ex: A descriptive study on biophysical profile of nursing
personnel working in OPD of selected hospitals of Chennai.
Biophysical profile is only one research variables.
• Bivariate study: If two variable under study.
• Ex: A correlation study on smoking & lung cancer among
families in urban slums of city Kolkata.
• Smoking- independent variables
• lung cancer- dependent variables
• Multivariate study: More than two variables.
• Ex: A study on factors contributing to noncompliance of
treatment among TB patients in selected rural communities of
district Patiala, Punjab.

26. • Continuous variables : Take values along a continum
& can assume an infinite number of values between two
points.
• Eg. Weight of infants between 2 and 3kg. 2.250,
2.450….
• Discrete variables : Has a finite number of values
between ant two points, representing discrete
quantities.
• Eg. How many children they had, answer 0,1,2 or more.
• Categorial variables: Variables that take on a handful
of discrete non-quantitative values.
• Eg. Blood group has four types – A, B, AB & o
• Dichotomous variables : when categorial variables
take on only two values. Eg. Gender – male & female.

27. • Heterogeneous variables : when an attribute is
extremely varied in the group under investigation.
• Homogeneous variables : if the amount of variability
is limited. Eg. Group of 2year children
• Attribute variables: it is often inherent characteristics
of the research subject. Eg. Age, weight, blood group.
• Active variables :Investigator introduces a new
intervention to make desired changes.
– Eg. Different group of patients are given different
analgesia method.

28. Summary
Hypothesis or Hypotheses are defined as the formal
statement of the tentative or expected prediction or
explanation of the relationship between two or more
variables in a specified population. It provides clarity
to the research problem and research objectives. It
describes, explains or predicts the expected results or
outcome of the research. There are various types of
hypothesis such as simple Vs complex hypothesis,
Research Vs Null hypothesis, directional Vs Non
directional hypothesis and associative Vs complex
hypothesis.

29. References
• Davies, J. (2012). Nursing & Health Survival Guide:
Evidence-based Practice. London: Routledge.
• Polit, D.F., & Cheryl, T.B. (2014). Essentials of Nursing
Research – Appraising Evidence for Nursing Practice.
Philadelphia: Wolters Kluwer.
• Pooler, A. (2014). An Introduction to Evidence-based
Practice in Nursing & Healthcare. New York: Routledge.
• Thyer, B.A. (2004). What is Evidence-Based Practice? Brief
Treatment and crisis Intervention, 4(2), 167-176.

30. THANK YOU