identification of variales

1. BY SAIMA HABEEB
Ph.D (N) SCHOLAR
RESEARCH PRESENTATION

6. VARIABLES

8. INTRODUCTION
“Variable” is a term frequently used in research projects.
It is pertinent to define and identify the variables while designing
quantitative research projects.
Variable, to put in layman statement is something that can change
and or can have more than one value.
It may be weight, height, anxiety levels, income, body temperature
and so on.
Some variables can be quite concrete and clear, such as gender, birth
order, types of blood group etc while others can be considerably
more abstract and vague.

9. MEANING
Any characteristic that varies from person to person,
place to place or time to time (Eg. Glomerular
filtration rate of an adult, Blood group of a person,
number of cigarettes smoked/day by a patient)
If it does not vary it is a constant (Eg. Earth’s
gravitation at a given altitude, energy in e = mc2 for a
given mass)
Most of the biological phenomena are variables

10. TERMINOLOGY
Sample
The set of subjects that we study form the study
sample
- They are part of a bigger target group
- They are representative of the Target group
Population
-The target of our investigation or the total/aggregate
is called the ‘Population

11. Eg. 1. If we wish to know the proportion of anemic
pregnant women in a village:
-Variable: Hemoglobin level (mg/dl)
-Sample: Selected small set of pregnant women Population:
All currently pregnant women in the village .
Eg. 2. If we wish to birth weight of newborns:
-Variable: Birth weight (gms)
-Sample: Selected newborn babies
-Population: All babies born in the clinic

12. • Variables
• Qualitative Quantitative
• Ordinal Nominal Countable Continuous Eg.
Disease status Blood group CD4 count Syst. BP
Mild, mod. sev. A, B, AB, O 110, 111, .., ? The
type of statistical analysis depends on the type
of the variable(s) that we deal with in a given
situation

13. Definition

14. Types of variables
Active and attribute variables
Continuous
Discrete
categorical variable

15. Independent & Dependent
variable

17. Identifying dependent and
independent variables
Variability in the dependent variable is presumed to depend
upon the variability in the independent variable.
- For example, researcher studies to which extent lung cancer
(dependent variable) depends on smoking (independent
variable).
A quasi-experimental study on effect of 4-hourly
chlorohexidine mouth wash on prevention of ventilator
associated pneumonia (VAP) among patients admitted in
selected ICUs of PGIMER, Chandigarh.
- In this study, 4 hourly chlorohexidine mouth-wash is an
independent variable and VAP is the dependent variable.

18. Research variables
• Variables that are observed or measured in a
natural setting without manipulating and
establishing cause and effect relationship.
• In descriptive, exploratory , comparative , and
qualitative research studies, variables are
observed or measured in natural setting as
they exist, without imposing the effect of
intervention.

20. Demographic variables
Characteristics and attributes of the study subjects are
considered as demographic variables.
They are also called sample characteristics. It means
these variables describe study sample and determine
if samples are representative of the population of
interest.
- Example: age, gender, education, religion, occupation,
habitat, income, medical diagnosis.

21. Extraneous variables
Factors that are not the part of the study but may
affect the measurement of the study variables.
These variables are usually recognized and controlled
by researchers in quasi-experimental studies.
Generally, specific research design and sample
inclusion and exclusion criteria are used to control
the influence of extraneous variables.

22. For example:
Effect of two different pin site care protocols on prevention of pin site
infection among patients with external skeletal fixation.
Pin site infection may also be influenced by some other factors such
as low Hb or high Blood sugar level, these factors are considered as
extraneous variables.

23. Continuous variables
They have a wide range of values.
The values are not restricted to the whole numbers.
They can assume an infinite number of values
between two points.
- Example: Weight is a continuous variable: between 1 and 2 pounds,
the number of values is limitless: 1.05, 1.8, 1.333 and so on.

24. Discrete variable
It has a finite number of values between any two
points, representing discrete quantities.
In this variable, the values are restricted to the whole
numbers.

25. Categorical variables
These variables take on a small range of values that
do not represent a quantity.
They take a handful of discrete non-quantitative
values.
- For example, Blood type has four values- A, B, AB and O.

26. Dichotomous variable
When categorical variables take on only two values,
they are called as dichotomous variables.
- For example: Gender is a dichotomous: male and female.

27. Identifying variables in
Quantitative Research Studies
After the key variables have been identified, the
researcher needs to identify how those variables will
be studied, which is the heart of the research design.

28. Descriptive A descriptive study on
prevalence of anemia
among adolescent girls in
selected villages of
Gulbarga, Karnatka.
Research Variable:
prevalence of anemia.
Exploratory An exploratory study on
contributing factors of
anemia among adolescent
girls in selected villages of
Gulbarga, Karnatka.
Research variable:
contributing factors of
anemia.
Correlational relationship between
motivation and academic
achievement.
experimental examine the effect of oral
morphine in management
of chronic cancer pain
among advanced stage
cancer patients admitted in
hospice at Chandigarh.
Independent variable: oral
morphine
Dependent variable:
chronic cancer pain.

29. Quasi Experimental Effect of needle gauze on
pain perception among
patients.
Independent variable:
needle gauge
Dependent variable:
Pain perception.
experimental Examine the effect of oral
morphine in management
of chronic cancer pain
among advanced stage
cancer patients admitted in
hospice at Chandigarh.
Independent variable: oral
morphine
Dependent variable:
chronic cancer pain.
Comparative: Comparative study on
health problems among
rural and urban older
people of district Ludhiana,
Punjab.
Research variable: Health
problems, urban/rural.

30. Identifying variables in
Quantitative Research Studies

31. Phenomenological :
Example: a phenomenological study on live
experiences of tsunami victims in selected villages of
Tamil Nadu.
Research variable: live experiences

32. Ethenographical :
Example: An ethnographic study on the features,
critical attributes and benefits of self-help groups of
women living with chronic alcoholic husbands in
selected villages of Tamil Nadu.
Research variable: features, benefits of self-help
groups.

33. Grounded theory
Example: A study on the response and adaptation
process of patients diagnosed with cancer in PGIMER,
Chandigarh.
Research variable: response and adaptation process.

34. Case study
Example: A case study on availability and utilization
of emergency services in public hospital at Ludhiana,
Panjab.
Research variable: Availability and utilization of
emergency services.

35. Historical study
Example: A historical study on experiences of ward
facilities for psychiatric nurses during 1970s in
NIMHANS, Banglore.
Research variable: Experiences of ward facilities.

36. CONCLUSION & SUMMARY:
Any concept that can be measured on measurement scales is
called a variable.
Variables are important in bringing clarity to
conceptualization of a research problem, for hypothesis
formulation and development of research instrument.
A variable can be classified into different categories based on
causal relationship, design of study and unit of measurement.
The four types of measurement scale are nominal, ordinal,
interval and ratio.
Thus, the most difficult part of planning the research study is
identifying the research variables. Considerable time and
thought needs to be given. Once the key variables have been
identified, then the research study can variables have been
identified, then the research study can be developed.

63. THANKING YOU