Sociology: Social Networks, Social Support
Biostatistics
College of Medicine University of Malawi
2011
1
Learning Objectives
By the end of this lesson you should be able Explain importance of Biostatistics Distinguish between types of variables Explain different types of measurement scales
2011
2
Page 1
Definition of Statistics
Statistics is the science that studies the collection and interpretation of numerical data. Field of statistics is divided into Mathematical and Applied statistics.
2011
3
Applied statistics concerns the application of the methods of mathematical statistics to specific areas such as public health, economics etc Biostatistics is the branch of applied statistics that concerns the application of statistical methods to medical and biological problems
2011
4
Page 2
Importance of Biostatistics
To better understand reports of research studies in your field To obtain a foundation in statistical issues for designing and conducting your own research. To learn a few techniques for analyzing data
2011
5
Variables, Measurement Scales and Summarizing data
2011
6
Page 3
Definition of a Variable
A variable is a characteristic that can have many different values.
2011
7
Types of Variables
A categorical variable has values with interruptions or gaps between them (categories) A continuous variable has values that could, theoretically, be measured without gaps
2011
8
Page 4
Scales of Measurement
Qualitative
Nominal Ordinal Binary
Quantitative
Discrete Continuous
2011
9
Qualitative
Consists of a finite set of possible values or categories Always categorical
2011
10
Page 5
Nominal scale
Qualitative categories which have no particular order. Examples:
Diagnosis
Malaria AIDS Accident Other
2011
Ethnic group
Chewa Yao Tumbuka
11
Binary scale
Two qualitative categories Examples: Gender
Male Female
HIV status
Uninfected Infected
2011
12
Page 6
Ordinal Scale
Qualitative categories that have a natural order. As a result, we can decide that one outcome is
College of Medicine University of Malawi
2011
1
Learning Objectives
By the end of this lesson you should be able Explain importance of Biostatistics Distinguish between types of variables Explain different types of measurement scales
2011
2
Page 1
Definition of Statistics
Statistics is the science that studies the collection and interpretation of numerical data. Field of statistics is divided into Mathematical and Applied statistics.
2011
3
Applied statistics concerns the application of the methods of mathematical statistics to specific areas such as public health, economics etc Biostatistics is the branch of applied statistics that concerns the application of statistical methods to medical and biological problems
2011
4
Page 2
Importance of Biostatistics
To better understand reports of research studies in your field To obtain a foundation in statistical issues for designing and conducting your own research. To learn a few techniques for analyzing data
2011
5
Variables, Measurement Scales and Summarizing data
2011
6
Page 3
Definition of a Variable
A variable is a characteristic that can have many different values.
2011
7
Types of Variables
A categorical variable has values with interruptions or gaps between them (categories) A continuous variable has values that could, theoretically, be measured without gaps
2011
8
Page 4
Scales of Measurement
Qualitative
Nominal Ordinal Binary
Quantitative
Discrete Continuous
2011
9
Qualitative
Consists of a finite set of possible values or categories Always categorical
2011
10
Page 5
Nominal scale
Qualitative categories which have no particular order. Examples:
Diagnosis
Malaria AIDS Accident Other
2011
Ethnic group
Chewa Yao Tumbuka
11
Binary scale
Two qualitative categories Examples: Gender
Male Female
HIV status
Uninfected Infected
2011
12
Page 6
Ordinal Scale
Qualitative categories that have a natural order. As a result, we can decide that one outcome is