This document provides an overview of research methodology. It discusses different types of health research including biomedical, clinical, epidemiological, and health systems research. It also covers research design approaches such as exploratory studies, descriptive studies including case studies and surveys, analytical studies including case-control studies, and experimental designs like randomized controlled trials. Key aspects of the research process are explained such as developing objectives, variables, hypotheses, literature reviews, and ethical considerations. Criteria for selecting good research topics and writing references are also presented.

1. Research Methodology
Dr. Sawsan Mustafa Abdalla
Associate Prof .faculty of medicine
.Community Department

2. Research
Research is “the systematic collection,
analysis and interpretation of data to
answer a certain question or to solve
a problem”

3. Purposes of Research
Research serves two Purposes :1- Generates new knowledge and
technologies to deal with major
health problems“ basic research”
2- Identifies priority problems ,
evaluates polices and programs
“applied research”

4. The importance of Research
Why do we carry out research ?
It is generally recognized that there
is a wide gap between data available,
and data needed for management ,
planning and decision making, so
research is needed to bridge this gap

5. Characteristics of research




It demands a clear statement of the
problem
It requires a plan
It builds on existing data
It collects new data

6. Classification of health research




Bio medial research
Clinical research
Epidemiological research
Health system research

7. Bio medical research-1


Bio Medical research focuses on the
individual
It concentrates on how the body
works i.e. Biological process , body
structure and functions , and the
pathological mechanisms occurring
within the body

8. Clinical research

Clinical research focuses on the
individual. It deals with the response
of the body to various preventive ,
diagnostic or therapeutic interventions
Example: The efficacy of long acting penicillin
on tuberculous patients

9. :-Epidemiological research



Epidemiological research focuses on
the population , and considers the
frequency , distribution and
determinants of diseases
Example:Epidemiology of malaria in Khartoum
state
Pattern of health problems in under
five children in Omdorman area .

10. .( Health system research (H.S.R


Health system research focuses on
how well is the health system
functioning , such as cost and quality
of health services etc
Health system research aims to
provide information which improve
the health system.

11. Types of Health system research


Operational research
Health policy research

12. Operational research
Operational research is the process
of identifying and solving health
program problems. It is designed to
improve effectiveness and quality of
health services delivered by health
providers , and the availability ,
accessibility and acceptability of
health services delivered .

13. Health policy research
It looks over the policies e.g. allocation
of resources

14. CRITERIA OF
A RESEARCH TOPIC
Percived discrepancy between what is-1
existing and what is expected
A question why this discrepancy- 2
exists
More than one answer to the question- 3
is expected

15. CRITERIA FOR SELECTION
A RESEARCH TOPIC
The problem selected for the research
should fulfill the following criteria:
1. RELIVANCE:-THE PROBLEM SHOULD BE
AN IMPORTANT HEALTH PROBLEM.
2. APPLICABLE:THE PROBLEM SHOULD
HAVE SOME CHANCE OF BEING SOLVED.
3. FEASIBILITY: THE RESEARCH SHOULD
BE FEASIBLE WITHIN THE AVAILABLE
RESOURCES.

16. CRITERIA FOR SELECTION
A RESEARCH TOPIC
4-Political acceptability
The ultimate goal of a research is to
provide decision – makers and
managers with results , so it is
advisable to choose a topic that has
the interest and support of the
authorities . This will increase the
chance for recommendations to be
implemented .

17. :URGENCY-5
Urgency of results needed
According to the urgency needed
for data , the researcher should
decide what research to be done
.first and which can be done later

18. Ethical acceptability-6
Ethical issues should be considered
when we are trying to choose a
research topic, for we may do harm
on others when we are carrying out
research. Acceptance of research by
the study subjects is important and
taking consents from them is always
.important

19. Avoidance of duplication- 7

Before you decide to conduct a research,
you should find out whether the suggested
topic was investigated before in this area or
another area with similar conditions. If the
topic has been investigated the results
should be reviewed to explore whether
major questions need further investigations,
if not this topic is not suitable for research
and should be discarded.
THE RESEARCH SHOULD BE COST/EFFECTIVE

20. RATING

21. grade
item
3
2
1
Relevance
.V.R
R
Not
Duplication
Not
partially
Fully
Applicability
V applic
.Applic
.Not app
Feasibility
.V.F
F
Not
Urgency
V. urgent
Urgent
not
P. acceptability
V. accepted
Accepted
not
.Ethical accep
No
minor
major
Total

22. :Definition of the problem

Once the researcher has decided on the
problem of the research, then he needs to
have a definition/description of the problem
written in a concise clear manner. It should contain
information such as:

Background information concerning the health
status of the community.



Basic description of the problem.
Justification.
Mention previous studies

24. Objectives

25. Objectives
The goals to be achieved by the
. research project
Why should the Objectives be
? developed
Focus the study (Narrow it down to-1
( essentials
Avoid collection of unnecessary data- 2
Organize the study in clearly defined- 3
parts

26. :Types
General: Identifies in general terms, what is to
be accomplished by the research
project.
Specific: Identifies in details the specific aims of
the research project

27. Example
:General
To study the reasons for low utilization of
MCH Services in Khartoum State –
2006
:Note
Gen. Objective is clearly related to the
.statement of the problem

28. : -Specific
-To determine the level of utilization
of MCH Services in Khartoum State
-To identify whether there are
variations in Utilization of MCH
Services and
- Seasons
- Type of clinics

29. Types of specific objectives
1. Estimation objectives
E.g. To determine incidence rate
2. Association objectives
Aims at Association between the factor of
interest and a particular event

30. ..Types of specific objectives- Cont
Example
To identify whether there is
Association of low utilization of MCH
clinics and mother education
3. Evaluation objectives:
To evaluate the effect of an
investigation
E.g. the effect of H.E. on utilization
of MCH services.

31. Characteristics of specific objectives
1- Simple, clearly stated & covers all the
aspects of the problem
2- Measurable
- Using action verbs: -e.g to identity, to
compare
- Avoiding non-action verbs: e.g. to
describe, to study, to notice…

32. Characteristics of specific objectives.Cont
3- Attainable: Can be achieved
4- Realistic: - Feasible concerning
resources
5- Timely: - To be conducted within
the allowed time frame of the study.

33. Properly formulated specific objectives
: -will help in
1.
2.
3.
Selection of the right type of design
Orientation of data collection
Evaluation of the study.

34. Hypothesis


A hypothesis is 'a prediction of a
relation ship between one or more
factors and the problem under study,
which can be tested.
A hypothesis is a frequent goal in
quantitative research.
E.g.
Consumption of more than 10
cigarettes / day for ten years is
associated with Ca. Bronchus.

35. Review of the available literature

36. Review of the available literature
.?Why do we review Lit
Prevents duplication. 1
Assist in refining statement of the. 2
problem
Strengthening the argument of . 3
of a research topicselection
((Justification
It helps to get familiar with various . 4
types of methodology that might be
(used in your study (Design

37. Source of information
Articles
- Books
- Indexes
- Abstracts from journals
International organization
documents
-
e.g. (WHO,UNICEF)

38. .Source of information- cont
- Reports from MOH facilities
- Vital statistics
- Census
- Surveillance system
- Surveys
-Computer search for international
Literature
-Opinions, beliefs of key persons
(Through
interview)

39. ?How to write lit review
Use index cards.Write in your own language-

40. Bias in literature review
-
-
-
The presentation of the available
information in such away that it
reflects opinions or conclusions
that does not represent the real
situation
Restricting references to those
that support the point of view of
the author.
Drawing far reach conclusions from
shaky or Preliminary results

41. Ethical considerations in lit.
Review
Bias- Careless presentation and
interpretation of data
Put researcher on the wrong way
- Loss of resources.
- Wrong decisions

42. How to write References
:From journals/ 1
Author (s). Article. Journal. Year;
Volume: Pages
(Author : Surname followed by initials)

43. How to write References
From a book/ 2
Author. Title of the book. Edition. Place:
.Publisher, Year: Pages
From a chapter in a book/ 3
Author (s). Chapter title, In: Editors of the
book. Edition. Title of the book. Place.
Publisher, Year: Pages

45. Study Variables

46. Study Variables
A variable is a characteristic of a
person, object or phenomenon that
can take different values and can be
.measured

47. Classification of Variables
: Numerical
Expressed in numbers, E.g. Weight,
height, Distance between homes and
…clinic etc
:Categorical
. Expressed in categories: E.g
...colors, ranks etc

48. Classification of Variables
1- Numerical variables: a- Discrete: - E.g. Episodes of
diarrhea, schist. eggs.
b- Continuous: - E.g. Weight, Height
2- Categorical variables: a- Ordinal: E.g. Doctors, soldier
ranksb- Nominal: E.g. colors, sex

49. Types of variables
: Dependant variable 1
.Use to measure the problem
: Independent variable2
cause or influence the problem
-: Confounding variables 3
Variables associated with the problem
.and its possible causes

50. Confounding variables
Cause
Effect
Independent variable
Cigarette smoking
dependent variable
Ca. bronchus
Confounding variable

51. : -Confounding variables
- May affect results (Bias)
- Must be considered
particularly in case -control
studies( matching)

52. ?How to write variables
Expressed in a neutral way
Factor
long waiting time
Absence of drugs
Variables
- Waiting time- Drug availability-

53. Operationalization of variables
Determine whether the variables are
measurable or need appropriate
indicators E.g. Level of Knowledge,
Nutritional status Weight/ age
,Weight/ height etc... (Standard
(growth curve

54. Research Designs

55. Study designs
.Non intervention stud
.Intervention stud
.Exploratory stud
.Case stud
. Descriptive stud
. Analytical stud
Randomized control Trials
Surveys
.Case con. Stud
Cohort study
. Quazai experimental stud

56. Exploratory study

57. Exploratory study
It is a small - scale study of relatively short
duration, which is carried out when little is
known about a situation or a problem
Exploratory studies problem is not as may
be descriptive and/ analytical. If the
problem is not well defined , it is always
.advisable to do an exploratory study

58. Exploratory study
:Example
One community with high and
another with low participation in
health activities, to identify the
factors that contribute to community
.participation

59. DESCRIPTIVE STUDY
DESIGNS
The systematic collection and
presentation of data to give a
clear picture of a specific
disease or a health related
events

60. a/ Case studies

61. Case studies
A case study describes in depth
the characteristics of one or
limited number of cases in its
natural environment

62. Case studies
A case may be a patient, a health…centre, a village etc
Can provide useful insight into theproblem e.g. a new disease
Common in clinical medicine, socialsciences, management and
..administration etc
Associated with qualitative data andpresentation is in a narrative way
-

63. Case studies
:Features
Should be well planned and data will be collected thorough predetermined
questions
Should be flexible to deal with unexpected situations

64. Case studies
:Advantage
It permits a holistic approach to the problem under investigation
:Disadvantage
Not representative -

65. b/ SURVEYS

66. SURVEYS
Use :
1. To collect information on
demographic characteristics.
Age, sex, education etc…
2. To study characteristics on
health related variables. E.g.
MMR, incidence rate, etc….
3.To study attitudes, opinions and
beliefs

67. SURVEYS
Surveys answer the following questions:
- WHEN IS THE DISEASE OCCURRING?
(TIME DISTRIBUTION)
- WHERE IS THE DISEASE OCCURRING?
(PLACE DISTRIBUTION)
- WHO IS AFFECTED? (PERSON
DISTRIBUTION)

68. PROCEDURE
Define the problem under- 1
study
2- DEFINE THE POPULATION
UNDER THE STUDY.
3- DESCRIBE THE DISEASE BY
TIME, PERSON AND PLACE.
4- MEASUREMENT OF THE
DISEASE.
5- COMPARING WITH KNOWN
INDICES.
6- FORMULATION OF AN
.AETIOLOGICAL HYPOTHESIS

69. CROSS SECTIONAL STUDY


PREVALENCE RATE STUDY
THE RELATIONSHIP BETWEEN
THE DISEASE & OTHER
VARIABLES OF INTEREST AS
THEY EXIST AT ONE PARTICULAR
POINT OF TIME

70. CROSS SECTIONAL STUDY OF
HYPERTENSION
1.
2.
3.
4.
5.
MEASURE THE B.P. AMONG THE
STUDY POPULATION
(PREVALENCE.)
COLLECT DATA ON AGE, SEX,
SOCIAL CLASS , OCCUPATION
etc...
DETERMINE HOW
HYPERTENSION IS RELATED TO
THESE VARIABLES
Compare with findings of others
Draw hypothesis

71. LONGITUDINAL STUDY DESIGNS

OBSERVATIONS ARE REPEATED IN
THE SAME POPULATION OVER A
PROLONGED PERIOD OF TIME
THESE ARE USEFUL IN:



STUDY THE NATURAL HISTORY OF
THE DISEASE.
IDENTIFY THE RISK FACTORS.
DETERMINE THE INCIDENCE RATE.

72. Analytical studies
1. Case Control study

73. Case Control study
In Case Control Study, the investigator
compare one group among which a
problem present, with another group
(control) where the problem is absent

74. Common features
1.
2.
3.
Both exposure and outcome have
occurred before the start of the
study
Study proceeds back from effect to
cause
Presence of a control group

75. Basic steps
1.
2.
3.
4.
5.
Selection of cases
Selection of controls
Matching
Obtaining data on exposure
Analysis and interpretation of
results

76. Selection of cases
It involves two specifications:
1. Diagnostic criteria:
Specific diagnostic criteria of the
disease, its staging are to be
stated clearly.
2. Eligibility criteria:
Criteria to determine who is
allowed to be included in the
study. E.g. Only newly diagnosed
cases rather than old ones

77. Sources of cases and controls
:Cases
-
Patients
General population
:Controls
-
Patients
Relatives
Neighbor hood
General population

78. Matching
Is the process by which controls are to
be similar to the study group
:Types


Individual matching
Group matching

79. :Analysis
1.
2.

The exposure rate among both the
cases and the controls.
Odds ratio: This ratio can be used
to estimate the relative risk as the
incidence rate can not be determined
in case-control study design.
Thus the case control study is
always suggestive of the etiological
association between two variables

80. Case control study of smoking and Ca. lung
Cases
status
smoking
Yes
No
Total
(a
c
Controls Total
)33 (b
(
)55
a+
(d
)27
c
)2
35
(a + c)
82
(b + d)
(b
)88
)29
(+ d
117
(a+b+c+d)

81. 


The exposure rate among cases=
a ÷ a+c = 33÷35= 0.94x100=94%.
The exposure rate among the
controls= b÷ b+ d=55 ÷82=
0.67x100=67%.
Odds ratio= a/c÷ b/d = a/c x d/
b=891÷110=8.1

82. INTERPRETATION


From the exposure rates among the
cases & controls: Chi square test has
to be used to confirm that there is
statistical difference between the two
values.
If the odds ratio is found to be
greater than one it means that there
is a positive etiological association.

83. Analytical studies
2. Cohort study

84. Cohort study


A longitudinal a study in which a
group of individuals are followed up
for some time.
A cohort is a group of persons who
share common characteristics or
experience within a defined time.

85. Features



The cohort is identified before the
appearance of the investigated
disease
The study groups are observed over
a period of time
The study proceeds from cause to
effect
Note: The incidence rate can be measured

86. :Indications of cohort study
1.
2.
3.
When there is strong suspicion of
association between exposure and
disease
When exposure is rare but the
incidence is high among the exposed
When the attrition of study
population can be minimized

87. Types of Cohort studies
:Historical Cohort studyStarts from a point in the past to now
:Prospective Cohort studyStarts from now and study goes on to the
future
Retrospective Prospective Cohort:study
Starts from the past, passing through now
and proceeds to the future

88. Elements of a cohort study
:Selection of a study group -1
From:- a. a general population or
b. Special group (Such as doctors, drivers etc.. or
(exposure group
:Obtaining data on exposure- 2
…By review of records , medical examination, interview etc
;Selection of a comparison group- 3
Internal comparisons: According to exposure levelExternal comparisons: From out side the study group-

89. .Elements of a cohort study- cont
:Follow up- 4
By: a. Periodic medical examination
b. Review of records
c. Review of death certificates
d. Mailed questionnaires
…e. Telephone calls etc
:Analysis- 5
a. Incidence rate
b. Relative risk

90. Analysis
Relative risk:
This is the ratio that measures the
strength of association between
suspected cause and effect.

91. Attributable risk
This is the difference in incidence of
disease or death between exposed &
non-exposed group. It is expressed as
a percentage.
It measures the impact that removal
of a certain factor will have on the
incidence of the disease.

92. SMOKING & CA. LUNG
Smoking
status
Developed
Ca lung
70
(a)
Did not
develop Ca
lung
6930
(b)
Yes
No
Total
7000
(a+b)
3
©
2997
(d)
3000
(c+d)

93. Analysis
Incidence rate of Ca lung
among smokers=
a/a+b=70/7000= 10/1000
 Incidence rate of Ca lung
among non-smokers=
c/c+d= 3/3000= 1/1000


94. Analysis

Relative risk=
Incidence of disease among exposed:
incidence among non-exposed
10/1000
1/1oo0.

Attributable risk= Incidence rate
among exposed-incidence rate
among non-exposed/incidence rate
among exposed= 10-1x100=90%.

95. EXPERIMENTAL STUDY
DESIGNS

96. EXPERIMENTAL STUDY DESIGNS
In experimental studies the researcher
manipulates a situation and measures
its effect after that
:Type
Randomized control trials- 1
Non-randomized trials- 2

97. Randomized control trials- 1

98. RANDOMIZED CONTROLLED TRIALS
Those trials are used for assessment
of methods of treatment and
prevention.
They include:
- intervention
- control groups and
- randomization

99. Features of Randomized control trials
:Manipulation- 1
The researcher does some intervention (Example provision of
.new drug) to one of the study groups
:Control- 2
The researcher introduces one or more control groups to
compare with the experimental group
:Randomization- 3
Each subject have an equal chance of being
allocated to either of the two groups( study and
(comparison groups

100. :-steps
1. Drawing a protocol.
2. Selecting comparison &
experimental groups
.Randomization. 3
4. Manipulation (intervention).
5. Follow up.
6. Assessment of the outcome.

101. THE PROTOCL
One of the essential features of the
randomized trials.
The protocol specifies:
1. The objectives.
2. The questions to be answered.
3. The selection criteria.
4. The sample size.
5. The procedures of allocation of the
subjects into experimental and
control groups.

102. . …THE PROTOCL- cont
6. The treatment applied: How,
what dose etc...
7. The details of the scientific
techniques and investigations.
:Note
Once the protocol has been evolved, it
should be strictly adhered to through out
the study.

103. RANDOMIZATION


Randomization is the statistical
procedure by which the
participants are allocated into
groups usually called study &
control groups to receive or not
to receive intervention or
therapeutic procedure .
Randomization aims at making
the groups comparable and
eliminate bias.

104. RANDOMIZATION



Randomization ensures that the
investigator has no control over the
allocation of the participants to either the
study or control group, thus eliminating
the selection bias.
Every individual has an equal chance of
being allocated into either group.
Randomization is best done by using
statistical random table.

105. MANIPULATION


Manipulation or intervention is usually
done by application or withdrawal of the
suspected factor e.g. drugs, vaccine or
dietary factor.
This manipulation creates an independent
variable (drug, vaccine or new procedure)
which effect is then determined by the
measurement of the final outcome which
constitutes the dependent variable e.g.
incidence of disease, recovery.

106. FOLLOW UP


This includes examination of the
study & control groups subjects at
defined intervals of time in standard
manner under the same conditions in
the same time frame till the final
assessment.
The main difficulties encountered in
the follow up process include:
Attrition from:- death, migration,
displacement and loss of interest etc

107. ASSESSMENT
The final assessment of the trial is carried in terms of:

Positive results:
These include the benefits of the experimental study
such as reduced incidence of the disease or severity
of the disease, cost of health services or other
appropriate outcome.

Negative results:
These include the severity & frequency of sideeffects and complications.
The incidence of positive/negative results is
compared in both groups and the differences are
tested statistically.

108. Non-randomized trials- 2

109. a. QUASI-EXPERIMENTAL STUDY DESIGNS


At least one of the characteristics of the true
experiment is missing (RANDOMIZATION OR
CONTROL GROUP)
QUASI-EXPERIMENTAL STUDY DESIGNS
ALWAYS INCLUDES MANIPULATION
( INTERVENTION)

110. Non-randomized trials. 2
b. Before and after study:
- Includes intervention
- No control group
- No randomization
- Observation before and after the
intervention
- Test ( analysis)

111. Bias in experimental studies


Bias is the systematic difference between
observed results and the actual results.
Sources of bias:
1. Participant’s bias:
The participants report subjectively that they
feel better or improved if they knew that
they were receiving new treatment.

112. . ..BIAS – cont
2.Observer’s bias:
The influence of the investigator measuring
the outcome of the trial if he knew
beforehand the particular procedure to
which the patient has been subjected.

113. ?How to reduce the sources of bias
1. Randomization.
2. Blinding.
Blinding is carried in three ways:
1. Single blind trial: The trial is so planned
that the participant is not aware whether he
belongs to the study or control group.
2. Double blind trial: The trial is so planned
that nether the doctor nor the participant is
aware of the group allocation and treatment
received.

114. How to reduce the sources of bias?
…Cont
3. Triple-blind trial:
The trial is so planned that the
participant, the investigator& the
person analyzing the data are all
blind.
This is the ideal but double-blinding is the
most commonly used.

115. DISADVANTAGES OF EXPERIMENTAL
STUDIES



They are costly.
Ethical problems.
Feasibility is difficult.

116. Sampling

117. Sampling
A sample is a selection of a
number of study units from a
defined study population

118. Questions to be asked
-
Study population:Population from whom the sample is to be taken
-
Sample frame:
A list of all units of study population from which the
sample is to be drawn
-
Sample size
Method of selection of the sample
Note
The sample should be representative, i.e. it should
carry the characteristics of the study population

119. Sampling methods
Divided according to the way of selection:
Probability sampling
Non-probability sampling

120. Probability sample- 1
It is a random selection procedures
that every unit of the study
population has an equal chance of
being selected in the sample

121. Types
1.
2.
3.
4.
5.
Simple random sampling
Systematic random sampling
Stratified sampling
Multistage sampling
Cluster sampling

122. Probability sampling- 1
1. Simple random sampling
1.
2.
3.
Give number to all the subjects
(List)
Determine the sample size
Select the sample using;
- A lottery or
- A table of random selection

123. Probability sampling - 1
2. Systematic random sampling
Used when there is a sample frame e.g. a
class, doctors in a hospital etc
:Steps
Determine the sample frame Determine the sample size Determine the interval Sample frame/ Sample size =
Note
First unit should be taken randomly

124. Probability sampling- 1
3. Stratified sampling
Used when the characteristics are not
equally distributed in the population
and the researcher is interested in
these characteristics to appear in the
analysis
.E.g
..Age, sex, religions etc

125. Probability sampling- 1
4. Multistage sampling
Used when the population is divided into subgroups
e.g. In a study of HIV/AIDS prevalence in the Sudan,
:the sample may be taken as follows
Take three states out of the 25 states Take two localities from each selected state Take towns and villages from each selected locality Take individuals from each town and village locality
Note
Multistage sampling usually involves more than one methods

126. Probability sampling- 1
5. Cluster sampling
Cluster sampling is the selection of study
.groups instead of individuals
Used when there is no complete sampling
frame, or there is some logistic difficulties
e.g. the population is composed of a large
. number of scattered villages
Note
Multistage sampling usually involves more than one
method

127. Advantages of multistage and cluster
sampling


A sampling frame is not required
The sample is easy to select
Disadvantage of cluster sampling:
-The sample may not be representative
Note:
Take more clusters and so big sample to
avoid this problem

128. Bias in sampling
1.
2.
3.
4.
Improper sampling procedure
Study of registered patients only
studying volunteers only
Tarmac bias: Study accessible
areas only

129. Non-probability sampling- 2

130. Non-probability sampling- 2
1. Convenience sample
-
Samples in which randomization is absent,
and so subjects have no equal chances of
being selected.
- For convenience, only those units which are
accessible at the time are taken.
- Used when there is no sample frame
- Many clinical based studies are from this type.
Problem:
Not representative

131. Non-probability sampling- 2
2. Quota sample
The population is divided into
categories and a quota is to be
surveyed from each category
:Problem
Not representative

132. Non-probability sampling- 2
3. Purposive sample
The researcher selects specific subjects in
the population and includes them in the
sample
:Problem
Not representative

133. Sample size
:For descriptive study
2
2
n= z . p q/ d
n = Sample size
z = Standard normal deviate = 1.96
p = Proportion of the characteristic
under study estimated in the target
population
q = 1-p
d = Error allowed = 0.05

134. Non-probability sampling- 2
4.Volunteer sample
Sample involves only those who are
accepting to introduce the study
:Problem
Not representative