Health Statistics by Ephantus Maina Mwangi
KENYA MEDICAL TRAINING COLLEGE
HEALTH STATISTICS
Prepared by: Lect. Ephantus Maina Mwangi
BTh, HND Epidemiology, Dip. Health Records & Information
Technology
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, Health Statistics by Ephantus Maina Mwangi
Table of Contents
Table of Contents..........................................................................................................................................i
HEALTH STATISTICS......................................................................................................................................1
SEMESTER I..................................................................................................................................................2
UNIT I (CHS 1.1) Introduction to Health Statistics and Data Collection........................................................2
Objectives................................................................................................................................................2
Definition of Statistics..............................................................................................................................3
Characteristics of Statistics......................................................................................................................4
Main Divisions of Statistics......................................................................................................................5
Functions of Statistics..............................................................................................................................5
Steps in statistical experiment.................................................................................................................6
Value and Importance of Statistics..........................................................................................................7
Uses or importance of statistics...............................................................................................................7
Limitations...............................................................................................................................................8
Distrust of Statistics.................................................................................................................................8
Types of Statistics....................................................................................................................................8
Identification of statistical/research problem..........................................................................................9
Objectives................................................................................................................................................9
What is research?....................................................................................................................................9
Definition of a Research Problem............................................................................................................9
Why Research?......................................................................................................................................10
Qualities of a Good Research Problem..................................................................................................11
Source of a Research Problem...............................................................................................................11
Aspects of a Research Problem..............................................................................................................12
Considerations in Selecting a Research Problem...................................................................................12
Research Topic.......................................................................................................................................13
Characteristics of a Good Topic.............................................................................................................13
Problems of Topic Selection...................................................................................................................13
Problem Statement................................................................................................................................14
FORMULATION OF RESEARCH OBJECTIVES/HYPOTHESIS......................................................................15
RESEARCH OBJECTIVES..........................................................................................................................16
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, Health Statistics by Ephantus Maina Mwangi
Why should research objectives be developed?....................................................................................17
How should you state your objectives?.................................................................................................17
HYPOTHESIS...........................................................................................................................................18
Characteristics of a good hypothesis.....................................................................................................18
Definition of Literature Review..............................................................................................................19
Purposes of Literature Review...............................................................................................................20
Planning a Literature Search..................................................................................................................20
Some tips about conducting the literature review................................................................................21
Content of the Literature Review..........................................................................................................22
SEESS: (Relevance of Carrying out Literature Review)...........................................................................23
What is critical literature review?..........................................................................................................23
Research methods.................................................................................................................................24
Terms related to research question.......................................................................................................25
What is a sample?..................................................................................................................................25
Sampling................................................................................................................................................26
What is a sampling frame?....................................................................................................................26
Sample Size............................................................................................................................................26
Sampling unit or element......................................................................................................................26
Sampling interval...................................................................................................................................27
Sampling Fraction..................................................................................................................................27
What is a representative sample?.........................................................................................................27
What is the difference between a statistic and a parameter?...............................................................27
Sampling Error.......................................................................................................................................27
Selection bias.........................................................................................................................................28
Statistical Inference:..............................................................................................................................28
Strata:....................................................................................................................................................28
Structured Question..............................................................................................................................28
SAMPLING TECHNIQUE..........................................................................................................................28
Why sample?.........................................................................................................................................29
Sampling methods.................................................................................................................................29
(a) Probability sampling methods..........................................................................................................29
1. Simple random sampling...................................................................................................................30
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, Health Statistics by Ephantus Maina Mwangi
2. Stratified sampling.............................................................................................................................31
3. Systematic sampling..........................................................................................................................32
4. Cluster sampling................................................................................................................................34
Steps of carrying out cluster sampling...................................................................................................34
Determining how many clusters to choose in a sample........................................................................35
5. Multistage sampling...........................................................................................................................36
(b) Non-probability sampling.................................................................................................................37
1. Quota sampling..................................................................................................................................37
2. Convenience sampling.......................................................................................................................38
3. Purposive Sampling or judgment samples.........................................................................................38
4. Snowball sampling.............................................................................................................................39
Advantages of probability sampling.......................................................................................................39
Disadvantages of probability sampling..................................................................................................39
Advantages of non- probability sampling..............................................................................................40
Disadvantages of non- probability sampling..........................................................................................40
Conclusion.............................................................................................................................................40
Determining Sample Size.......................................................................................................................40
ERRORS Vs MISTAKES................................................................................................................................42
Sources of error.................................................................................................................................42
Error of origin.....................................................................................................................................42
Error of manipulation........................................................................................................................42
Error of inadequacy...........................................................................................................................42
Kinds of error.....................................................................................................................................42
Sampling errors..................................................................................................................................42
Non sampling errors..........................................................................................................................42
Biased error.......................................................................................................................................42
Unbiased error...................................................................................................................................42
Sampling Errors And Biases................................................................................................................43
Non-sampling error............................................................................................................................43
Bias in Information Collection............................................................................................................43
Possible sources of bias during data collection:.................................................................................44
DATA COLLECTION.....................................................................................................................................47
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KENYA MEDICAL TRAINING COLLEGE
HEALTH STATISTICS
Prepared by: Lect. Ephantus Maina Mwangi
BTh, HND Epidemiology, Dip. Health Records & Information
Technology
0|Page
, Health Statistics by Ephantus Maina Mwangi
Table of Contents
Table of Contents..........................................................................................................................................i
HEALTH STATISTICS......................................................................................................................................1
SEMESTER I..................................................................................................................................................2
UNIT I (CHS 1.1) Introduction to Health Statistics and Data Collection........................................................2
Objectives................................................................................................................................................2
Definition of Statistics..............................................................................................................................3
Characteristics of Statistics......................................................................................................................4
Main Divisions of Statistics......................................................................................................................5
Functions of Statistics..............................................................................................................................5
Steps in statistical experiment.................................................................................................................6
Value and Importance of Statistics..........................................................................................................7
Uses or importance of statistics...............................................................................................................7
Limitations...............................................................................................................................................8
Distrust of Statistics.................................................................................................................................8
Types of Statistics....................................................................................................................................8
Identification of statistical/research problem..........................................................................................9
Objectives................................................................................................................................................9
What is research?....................................................................................................................................9
Definition of a Research Problem............................................................................................................9
Why Research?......................................................................................................................................10
Qualities of a Good Research Problem..................................................................................................11
Source of a Research Problem...............................................................................................................11
Aspects of a Research Problem..............................................................................................................12
Considerations in Selecting a Research Problem...................................................................................12
Research Topic.......................................................................................................................................13
Characteristics of a Good Topic.............................................................................................................13
Problems of Topic Selection...................................................................................................................13
Problem Statement................................................................................................................................14
FORMULATION OF RESEARCH OBJECTIVES/HYPOTHESIS......................................................................15
RESEARCH OBJECTIVES..........................................................................................................................16
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, Health Statistics by Ephantus Maina Mwangi
Why should research objectives be developed?....................................................................................17
How should you state your objectives?.................................................................................................17
HYPOTHESIS...........................................................................................................................................18
Characteristics of a good hypothesis.....................................................................................................18
Definition of Literature Review..............................................................................................................19
Purposes of Literature Review...............................................................................................................20
Planning a Literature Search..................................................................................................................20
Some tips about conducting the literature review................................................................................21
Content of the Literature Review..........................................................................................................22
SEESS: (Relevance of Carrying out Literature Review)...........................................................................23
What is critical literature review?..........................................................................................................23
Research methods.................................................................................................................................24
Terms related to research question.......................................................................................................25
What is a sample?..................................................................................................................................25
Sampling................................................................................................................................................26
What is a sampling frame?....................................................................................................................26
Sample Size............................................................................................................................................26
Sampling unit or element......................................................................................................................26
Sampling interval...................................................................................................................................27
Sampling Fraction..................................................................................................................................27
What is a representative sample?.........................................................................................................27
What is the difference between a statistic and a parameter?...............................................................27
Sampling Error.......................................................................................................................................27
Selection bias.........................................................................................................................................28
Statistical Inference:..............................................................................................................................28
Strata:....................................................................................................................................................28
Structured Question..............................................................................................................................28
SAMPLING TECHNIQUE..........................................................................................................................28
Why sample?.........................................................................................................................................29
Sampling methods.................................................................................................................................29
(a) Probability sampling methods..........................................................................................................29
1. Simple random sampling...................................................................................................................30
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, Health Statistics by Ephantus Maina Mwangi
2. Stratified sampling.............................................................................................................................31
3. Systematic sampling..........................................................................................................................32
4. Cluster sampling................................................................................................................................34
Steps of carrying out cluster sampling...................................................................................................34
Determining how many clusters to choose in a sample........................................................................35
5. Multistage sampling...........................................................................................................................36
(b) Non-probability sampling.................................................................................................................37
1. Quota sampling..................................................................................................................................37
2. Convenience sampling.......................................................................................................................38
3. Purposive Sampling or judgment samples.........................................................................................38
4. Snowball sampling.............................................................................................................................39
Advantages of probability sampling.......................................................................................................39
Disadvantages of probability sampling..................................................................................................39
Advantages of non- probability sampling..............................................................................................40
Disadvantages of non- probability sampling..........................................................................................40
Conclusion.............................................................................................................................................40
Determining Sample Size.......................................................................................................................40
ERRORS Vs MISTAKES................................................................................................................................42
Sources of error.................................................................................................................................42
Error of origin.....................................................................................................................................42
Error of manipulation........................................................................................................................42
Error of inadequacy...........................................................................................................................42
Kinds of error.....................................................................................................................................42
Sampling errors..................................................................................................................................42
Non sampling errors..........................................................................................................................42
Biased error.......................................................................................................................................42
Unbiased error...................................................................................................................................42
Sampling Errors And Biases................................................................................................................43
Non-sampling error............................................................................................................................43
Bias in Information Collection............................................................................................................43
Possible sources of bias during data collection:.................................................................................44
DATA COLLECTION.....................................................................................................................................47
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