1. By Dr Aijaz Ahmed Sohag
Prep by: Abdul Wasay Baloch
Amna Inayat Medical College
Data

2. Data
collecting
classifying
Summarizing analyzing
Interpreting numerical
data
Variables
Qualitative
Quantitative
Discrete
Continuous
Ordinal
Nominal

3. Continuous:
Blood pressure , height
weight
Discontinuous :
No of children
No of attacks of asthma per
week
Qualitative

4. Categorical
Ordinal
 Ordered categories
 Grade of breast cancer
 Better, same or worst
 Disagree, neutral, agree
Nominal
 Sex
 Alive or dead
 Blood group O, A, AB

5. Qualitative
 Countable facts
 Discrete
 Only frequency changes
 Can be expressed in rate
ratio
 Use Bar, Pie, Picto and spot
maps
 Test used – chi square,
Standard error of
proportion
Quantitative
 Measureable facts
 Continuous
 Both frequency and
variable changes
 Expressed as mean, median
and mode
 Rest all diagrams, such as
histo scatter and other
 Test used – ANOVA,Z test
and T Tesst

6. Data Defines as
 ‘’ collection of observation in scientific way’’

7. Types
 It has two types
 Qualitative
 Quantitative

8. Qualitative Data
 Qualitative data is categorized as data expressed not in terms
of number, e.g. favorite color, height is tall
 TYPES:
 Normal : when there is not a natural ordringof the categories,
e.g. gender, race, religion
 Ordinal or Ordered/ Ranked Data: when the categories: when
the categories may be ordered, these are called ordinal variable
e.g. small, medium, large
 NOTE that the distance between these categories is not
measured
 Used for both qualitative and quantitative

9. Quantitative
Data

10. Quantitative Data
 It is a numerical measurement expressed in terms of
numbers
 However, not all the numbers are continuous and
measureable
 E.g. favourite color = 450 nm, height = 1.8m

11. Discrete
 When you just count the numbers e.g 10 pencils
 Can not be expressed in decimal
 Thought countable, take only whole number values e.g. No of
children

12. Continuous
 This is measured on some scale
 It has no ends
 E.g. counting the pulse rate of class
 Measuring BP
 Can be measured in decimal
 May be measure as fractional values e.g. 17.4C, 162.5 cm etc)

13. Variables
 Characteristic :
 Any characteristic whose value is different from one individual
to another e.g. height of school boy
 A variable is any characteristic which is measured or observed
 It is denoted by X
 Variables are characteristics associated with the subjects of
study e.g. height weight, gender
 Variables so called because they tend to vary between subjects
 Broadly variables are grouped into quantitative and qualitative
variables

14. Quantitative Variables
 Data can be further classified beig qualitative or quantitative
 The STATISTICAL ANALYSIS that is appropriate depends
on whether the data for variable is qualitative or quantitative
 In general, there are more alternatives for statistical analysis
when the data are Quantitative

15. Quantitative Data
 Indicate either how many or how much
 Always numeric
 Ordinary arithmetic operation (e.g. +,- etc) are meaningful
only with QULITATIVE DATA