Research Protocol Development
Research Protocol Development
MODULE ONE
RESEARCH PROTOCOL
DEVELOPMENT
NOEL L. ESPALLARDO, MD
CLINICAL ASSISTANT PROFESSOR
DEPARTMENT OF FAMILY AND COMMUNITY MEDICINE
UNIVERSITY OF THE PHILIPPINES COLLEGE OF MEDICINE
LECTURE I
RESEARCH IDEAS, RESEARCH QUESTION AND
RESEARCH OBJECTIVES
Preparing for your research project
RESEARCH IDEAS
One conducts research because of pure interest, or it is a career or it is a requirement for
promotion, training or even recognition. Whatever is the purpose of conducting a research one
has to start with a good research idea.
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Focusing Research Ideas
Many research ideas do not materialize because they are vague or too broad. Although a
research idea may have one primary problem and a couple of secondary problems, it is advisable
that for a beginning researcher focusing on just one research problem is enough. There is no
formula on how to focus the research idea into a research question. It all depends on the interest
of the researcher. The examples below can serve as a guide on how to focus the research idea.
A young researcher wanted to study better ways to improve the success of TB treatment.
There are so many ways that TB treatment can be improved. So the researcher focused in
improving compliance because it is a grave problem among TB patients. The researcher further
considered that decreasing the frequency of medication with slight dose modification or directly
observing the intake of medication will improve compliance. In this scenario however, two
factors are being considered i.e. decreasing frequency and observing therapy that may have a
confounding effect on compliance. To avoid complications the researcher eventually chose to
study the effect of directly observed therapy on treatment compliance.
The example above started from a general idea of improving success of TB treatment to a
more focused research idea of investigating the effect of directly observed treatment to
compliance of TB treatment.
RESEARCH QUESTION
The research question is a long statement intended to focus the research project. It is
usually written in the latter part of the introduction. In a protocol it should be stated in such a
way that it can be answered by a yes or no. It usually embodies the research objectives.
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Below is an example of a research question on the effectiveness of a surrogate observer in
the treatment of tuberculosis.
“Among patients consulting at the local health center and diagnosed to have PTB
randomized to a clinical trial, will compliance to TB treatment be improved by encouraging a
family member to be a surrogate observer to drug intake compared with usual clinic advise?”
Biologic rationale yes, family members can encourage drug intake thereby
improving compliance
Specific population patients diagnosed to have PTB in a community health center
Specific test intervention use of surrogate observer for drug intake
Specific primary outcome of improving compliance to TB chemotherapy
interest
Specific comparative usual clinic advise
intervention
Suggestion of a study design randomized clinical trial
The criteria for a god research question is best remembered by the mnemonics F-I-N-E-S-
T (which stands for F-feasible, I-interesting, N-novel, E-ethical, S-significance and T-time bound).
Thus in undertaking a research project, the research question must at least fulfill these criteria.
Feasibility
Before you waste your time and effort in a particular research plan, first make sure that
the undertaking is feasible. Feasibility can be affected by several factors, but the most prominent
may be the cost of the project and the availability of study population. It is extremely difficult to
conduct a study that needs P 1 million in funding if the available amount is only P 1 hundred
thousand. Likewise it is difficult to study a disease that is very rare in a population. It will take a
whole lifetime before you can adequately accumulate your cohort.
Interesting
This may depend on whose perspective is the research question being evaluated. It is
helpful to view the interest first from the investigator, second from the patient and third from the
health care provider.
Novel
A good research always contribute new information.
Ethical
A research project will definitely not pass the institutional review board if the study is
not ethical. A study therefore must not place the participants in unnecessary risk or deny them of
the necessary benefits. It should also not infringe on their privacy.
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Significance
Just like interest, significance may be viewed from a different perspective. Significance
may also be evaluated in the same manner as interest.
Time Bound
It is very important that when you undertake a study, it should be finished at least within
your lifetime (or within your training, or within your deadline).
To make sure that your research question is a good one, apply the checklist as shown in
Table 1.
Elaborate significance
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2. Is enough known about the problem?
To answer this question a thorough search of the medical literature should first be done.
An electronic database search is usually more efficient than a hand search of printed journals in
the medical library.
4. Is it a priority problem?
If the answers to the questions above are all yes, then your study is significant. The next
question to answer is “Is it feasible?” To answer this first make a general plan of your study.
Follow the outline suggested in Table 2. Then ask the three questions below.
If the answers to the questions above are all yes, congratulations you’re now ready to
prepare your research protocol.
After formulating the research question and study plan a few problems might arise and
this might lead you to discard the research project. However there are solutions I would like to
suggest before discarding your research idea. First is consult Table 3 and adopt the suggested
solutions for the problems. Then present your study plan to you friends, colleagues and mentors
for comments and suggestions. This is the iterative process of forming a research proposal. Lastly
rely on your creativity, judgment and tenacity.
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Table 2 The Research Plan
Title
Investigator/s
Research Question
Objectives
Study Design
Study Population
Inclusion Criteria
Exclusion Criteria
Sample Size
Intervention
Experimental
Control
Outcomes
Procedures for
Measurement of
Outcomes
Statistical Analysis
Total
Budget/Schedule/Perso
nnel
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Table 3 Problems and Solution for a Difficult Research Question or
Research Plan
Problems Solutions
Vague or inappropriate Write the research question at an early stage.
research plan Get specific in the study plan about:
how the subjects will be sampled
how the outcomes will be measured
Think of ways on how to make:
the subjects more representative of the population
the measurements more representative of the phenomena of
interest
Not Feasible
Too broad Specify a smaller set of outcomes or variables
Narrow the question
Too expensive Consider less costly study design and measurement methods
Seek additional financial support
Decrease sample size?
Not interesting, novel or Modify the research question
significant
Uncertain ethical Consult institutional review board
considerations Modify research question
After formulating your research question, the next step is to formulate your research
objectives from the research question. The aims, goals, or objectives are the building blocks of a
research proposal. They provide a picture of what you plan to accomplish in your research
project.
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General Objective
Usually expressed in a broad health care issue or statement. The statement should
include the disease it wants to study, the aspect of disease that the project intends to change and
the setting where the change will occur.
For example, a researcher wanted to investigate the use of quality of life as an outcome
for the treatment of hypertensive patients in family practice, the general objective may be stated
as:
“The general objective of this study is to improve the care and treatment of hypertensive patients
in family practice.”
This general objective can also apply to a study that test a new anti-hypertensive
medication that may offer better BP control , improved survival and lower side effects.
Another researcher who is interested in trying to validate the modified Prime MD, a
screening instrument to detect psychological problems in family practice may state the general
objective as:
“The purpose of this study is to improve the screening program for psychological problems in
family practice.”
Avoid these:
“To validate the modified Prime MD.”
“To use the Prime MD as a screening tool in primary practice.”
In the example of the study on directly observed therapy the general objective can be
stated as:
“This study aims to improve the treatment of tuberculosis in the community setting.”
In the example of the effect of education on the patient and family members, the general
objective can be stated as follows:
“The general objective of this study is to improve the treatment of hypertensive patients.”
Specific Objectives
The specific objective involve a specific clinical question that is usually embodied in the
research question. Some author write their specific research objectives based on the methodologic
strategy like describing the population, measuring the outcome and analyzing the outcome as
shown below.
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Specific objectives for the study on TB compliance:
1. To diagnose patients with PTB based on chest x-ray or sputum examination.
2. To educate the patient or the patients family to act as surrogate observer for drug intake.
3. To measure compliance of drug intake in the two groups.
4. To compare drug compliance between the two groups.
There is no definite rule on how to formulate the specific objectives but it should follow
the SMART criteria. Special attention however should be given to the action verb used in the
statement of objective. The action verb must be clear and specific. The choice of the verb may
actually be the basis of the statement fulfilling the SMART criteria. For example the action verb
“to know” may be more appropriately stated as “to determine”.
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LECTURE II
METHODOLOGY I: OVERVIEW OF STUDY DESIGNS
Comparative Studies
These study designs compare the presence or absence of a cause or an outcome
characteristics between two groups. It is a better design to establish cause and effect relationship.
Observational Studies
These studies are designed to attempt to define the relationship between the outcome
and its causes (cause and effect relationship). The outcome can be a development of a disease or
cure of a disease and the cause can be a risk factor such as genetic predisposition, an
environmental exposure or unhealthy behavior like smoking, sedentary lifestyle etc. In this
designs the researcher do not manipulate the exposure of the subject to the cause but only
observe for their presence or absence. For example the researcher do not decide on the
environmental exposure, or who should have sedentary lifestyle or smoke. Manipulating them
may be difficult or even unethical especially when the outcome being observed is potentially
harmful.
There are two types i.e. case-control studies and cohort studies. They are described
below.
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Case-control Studies
In a case-control study, inclusion of subjects starts with defining or selecting those who
have the outcome or effect. These are considered as cases. Then this group is compared with
subjects who don’t have the outcome or effect. These are considered as the controls. Both the
cases and the control should be taken from within the same population. Then the two groups are
investigated as to the presence or absence of hypothesized causes or risk factors for the outcome.
Example in the literature (Shapiro et al. Oral contraceptive use in relation to myocardial
infarction. Lancet 1979; 1:743-747.)
A group of researcher examined the relationship between oral contraceptive and
myocardial infarction. They selected 234 women who develop myocardial infarction (cases) and
1,742 women who did not have myocardial infarction (control). Then they were all questioned
about history of oral contraceptive use. The results are shown below.
MI No MI
OC use 29 135
Non OC user 205 1,607
Total 234 1,742
A history of OC use was reported in 12.4% of cases and 7.7% of controls. We might say
that there is an association between OC use and MI because if there is none the proportion of MI
cases should be the same for both groups. The validity of the association however is dependenet
on the manner of population sampling or selection and determination of exposure.
Cohort Studies
A cohort is any group of individuals who share the same characteristics. In a cohort
study, selection of subjects start with identifying individuals who have the same characteristics or
presence or absence of a particular cause or exposure. They are then divided into two groups,
those with the characteristics or causes and those without the characteristics. They are then
observed forward in time and determine who among them develop the outcome or effect.
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General steps in doing a cohort study:
1. Identify a group or cohort who have the exposure or characteristics of interest in a
certain population.
2. Identify a group or cohort who don’t have the exposure or characteristics of interest.
3. Observe these two groups forward in time for the outcome of interest (data collection).
4. Analyze the data
Thg results show that 22.2% of cigarette smokers died compared to only 16.1% of non-
smokers within 20 years of follow-up. If there is no association between smoking and early
mortality the observed proportion should be the same in both groups. Thus smoking increases
mortality in the general population. The validity of this conclusion also depend on the selection
of the population and determination of exposure and outcome.
Experimental Studies
In this studies, there is manipulation in the exposure to the cause to establish its relation
with the outcome. Manipulation may be ethical when the outcome being studied is potentially
beneficial, for example testing a new drug that has advantage over the old one. It is therefore not
ethical to do experiments in humans if the experimenter wants to see the effect of different
radiation exposure to radiology technicians.
True experiments are randomized controlled trials. Non-randomized or uncontrolled
trials are considered quasi-experimental design.
Quasi-experimental Studies
Quasi-experimental designs are non-randomized, or non-comparative studies that
involve observation of the effect of a particular intervention. In a non-randomized comparative
study, the investigator choose two groups and assign each group to the two type of intervention
by convenience. The outcome is then compared between the two groups. In a non-comparative
study the investigator administer an intervention to a group of patients and watch the effect
before and after the study. The outcome is then described before and after the intervention. Some
authors consider non-comparative studies as case series, others as before-and-after design, but for
the purpose of the classification we have adopted, we will label them as quasi-experimental
study.
Example (Villamangca, D. Effects of Patient Education on the Quality of Life of Patients with
Bronchial Asthma, Dept Internal Medicine, Rizal Medical Center)
An investigator assembled a group fo asthmatic patients and enrolled them to an asthma
education program. The program consists of a series of group lectures and interactive discussions
patterned after the comprehensive asthma education program of the Philippine General Hospital.
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At the same time he also assembled a group of asthmatic patients and educate them in the
outaptient clinic. He measured the quality of life of both groups before and after the educational
intervention. The results of AQLQ after the educational intervention are shown below.
The results showed higher scores for the intervention group but the difference were not
statistically significant. Further analysis showed that baseline AQLQ in the usual education
group was really low from the start compared with the intervention group. This is the usual
problem with a non-randomized design.
In most but not all cases blinding is done. Blinding is the process in which the subjects,
investigator and other personnel in the study is not made aware of the type of intervention the
subject is recieving. This will be discussed in more detail later.
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Trandolapril Placebo
Overall deaths 304 (34.6%) 369 (42.3%)
Cardiovascular deaths 226 (25.8%) 288 (33.0%)
Non-cardiovascular deaths
78 (8.9%) 81 (9.3%)
The results of the study showed that the all-cause mortality, cardiovascular and non-
cardiovascular mortality were all lower in the trandolapril group. Trandolarpil therefore improve
survival among patients who have LV dysfunction and post-MI. The validity of this conclusion
depends on the selection and randomization of patients, manner of intervention and
determination of outcome.
Meta-analysis
A meta-analysis is a procedure that integrates and combine the results of two or more
primary studies that are similar in the population enrolled the intervention used and the outcome
measured. The pooled result is then subjected to a statistical analysis. A well conducted meta-
analysis allow a more objective appraisal of the existing evidence about a problem than a
traditional review or overview. It may also be biased owing to the inclusion or exclusion of some
irrelevant or relevant studies respectively.
Economic Analysis
Economic analysis can be defined as an analysis that uses analytic techniques of from
primary studies to define the choices in resource allocation.
In this design the cost of a particular intervention is estimated. Estimation include direct and
indirect costs. There are three types of economic analysis depending on the type of outcome. If
the outcome being considered is effectiveness of treatment, it is called cost-effectiveness analysis.
If the outcome is savings in terms of monitary units it is called cost-benefit analysis. If the
outcomes are equal and the cost is the only one being compared it is called cost minimization.
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experimental study. The algorithm in Figure 1 might be very helpful in deciding what research
design to use.
Yes No
Are you studying causation, Are you describing a
prognosis, treatment or diagnostic single case or groups of cases?
tests or just compare
clinical characteristics?
Yes No
Are you going to assign Are you going to recruit
treatment or exosure? those with exposure or
those with outcome?
Exposure Outcome
Retrospective Cohort Retrospective Case-
control
Yes No
Will you randomize? Are you going to recruit
those with exposure or
those with outcome?
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WORKSHOP I
2.
3.
2.
3.
2.
3.
Specific
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LECTURE III
METHODOLOGY II: STUDY POPULATION,
RANDOMIZATION, AND SAMPLE SIZE ESTIMATION
STUDY POPULATION
The larger group to which the study results are to be generalized is called the target
population. Thus if one is studying a new drug for the treatment of hypertension, the target
population is all the hypertensive patients in the world. It is however impossible to study all of
them thus we only choose a representative group. This is called the study or sample population.
The study population must be defined in the early stage of the study. It should be
appropriate enough to attain the objective of the study. For the study population to be clearly
defined, we should be guided by the following questions:
1. What or who should be the study population?
2. When and where should the study population be recruited?
3. How should the study population be selected?
Probability Sampling
Random sampling is a process whereby each unit in the population has the same
probability of being chosen – chance alone will decide which of the unit will be included. The
steps in doing random sampling is illustrated in Table 5.
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Table 4 Formulating Inclusion and Exclusion Criteria
Step 1 Prepare the sampling frame, usually a list of the target or accessible population
Step 2 Decide on the size of the sample
Step 3 Get a table of random numbers, arbitrarily select a starting point then get a series of
random numbers equal to the sample size. The numbers in the series that correspond
to the list are the subjects of the study. This process is called simple random sampling.
Another way is by systematic random sampling where the total number in the list is
divided by the sample size to get the sampling interval. Randomly select a starting
point in the list and include the subject in the list at every sampling interval. This is
equal to simple random sampling as long as the list is not arranged in a particular
order.
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Special Types of Random Sampling
Stratified random sampling – the accessible population is first divided into non-
overlapping strata such as range of age, sex, economic status etc. In each strata subjects are
randomly selected either by simple or systematic random sampling.
Disproportional sampling – if different strata have different size, sampling can be done
whose size is proportional to the size of the strata that may lead to different sizes between
different strata.
Cluster sampling – sampling is done from similar units of the population like 5 clusters
of provinces in the Philippines. This can also be done at several stages or multi-stage cluster
sampling. For example we want to study the prevalence of TB in the Philippines and we need
1,500 barangays, we can start with a cluster of 30 provinces, a cluster of 5 towns in each province
then a cluster of 10 barangays in each town selected.
Non-probability Sampling
The most common non-probability sampling is convenience sampling. In this method
subjects are chosen based on their availability i. e. during the time of consultation, those who
respond to the announcement or those who are near the study center etc. Purposive sampling is
another common method wherein a researcher selects a certain subject because they fulfill some
specific criteria. In snowball sampling, a subject who was already included are asked to identify
others who also have the same requisite characteristics. Stratified non-probability sampling can
also be done by quota sampling where volunteers are called to join the study and stop
recruitment in each strata once the proper size is achieved.
RANDOMIZATION
As previously mentioned the randomized controlled trial is the design considered as the
“gold standard” in clinical research. Randomization is an essential feature of such design. It is
defined as the process in which each subject is given the same chance of being assigned to the
different study groups. The purpose is to make the groups comparable with respect to known
and unknown variables that might affect the outcome of the study.
Several methods of randomization is available, but in this module we will only discuss
randomization with fixed allocation. This means that the randomization will not be alter as the
study progress.
Simple Randomization
The simplest method of randomization is by a toss of a coin. If the coin turns up heads
the subject is assigned to A, if the coin turns up tails the subject is assigned to B.
Another simple randomization procedure can be done using the table of random
numbers. The steps in doing randomization using the table of random numbers are described in
Table 6.
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Table 6 Steps for Randomization Using the Table of Random Numbers
Step 1 Decide what group to assign odd numbers and even numbers and how to generate a
series of random numbers in series or in columns
Step 2 Get a table of random numbers and point with a pencil where to start while being
blindfolded (another way is to use a series of seed numbers)
Step 3 From the starting point get the sequence of random numbers equivalent to the
expected sample size in the study
Step 4 Assign the groupings whether the number is even or odd
The use of computer generated randomization can also be done using the software called
RALLOC.
Simple randomization is easy to implement but may result to unequal sample sizes in the
study groups. This problem can be solved by blocked randomization.
Block Randomization
Blocked randomization is used to avoid imbalance in the number of subjects assigned to
each group. If 20 subjects will be randomized to two groups using simple randomization might
result to 12 subjects being assign to one group and 8 to the other. In blocked randomization each
block, say 4, is designed to have equal number of A and B by enumerating the possible
combinations of 2 A’s and 2 B’s (AABB, ABAB, ABBA, BAAB, BABA, BBAA). The combinations
are then selected at random until all 20 subjects are randomized (see Table 7).
Step 1 Number the following combinations of A and B in blocks of four as shown below.
1 2 3 4 5 6
A A A B B B
A B B A A B
B A B A B A
B B A B A A
Step 2 Randomly select five sequence of numbers from 1 to 6, say 3, 5, 1, 6, 1.
Step 3 The randomization therefore is as follows
Subj Assign Subj Assign Subj Assign Subj Assign Subj Assign
1 A 5 B 9 A 13 B 17 A
2 B 6 A 10 A 14 B 18 A
3 B 7 B 11 B 15 A 19 B
4 A 8 A 12 B 16 A 20 B
Stratified Randomization
In stratified randomization, prognostic factors that may affect the outcome such as age,
severity of illness etc. are identified. They are then divided into different strata such as less than
20 as the first strata, 20-50 as the second strata, and greater than 50 as the last strata. The subjects
in each strata are then randomized (simple or blocked) to their group assignments.
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SAMPLE SIZE ESTIMATION
The formula to be used for estimating the sample size may depend on the type of the
study and the outcome to be measured. For the purpose of simplification, we will discuss
computation primarily based on the type of outcome being measured and whether we are just
describing a single population or comparing two populations. Only the formulas and the needed
data to compute for the sample size will be presented.
Alpha = 0.05
Beta 1-tailed 2-tailed
0.5 2.71 3.84
0.2 6.18 7.85
0.1 8.56 10.51
Confidence Level
0.80 0.90 0.95 0.99
Za 1.28 1.64 1.96 2.58
Note Value of Zb at 0.10 is 1.28
Sample size estimation to describe a single population, rate or proportion as the outcome
measure:
N = Za2 PQ
d2
Where:
N – sample size needed
Za – value of Z in normal distribution at desired alpha level
P – estimated rate or proportion of the population with the outcome
Q – estimated rate or proportion of the population without the outcome
or (1-P)
d – maximum tolerable error
Example
A community physician wanted to estimate the prevalence of TB among schoolchildren
in a certain community. Previous study showed that the prevalence was 20%. He wanted to
estimate the present prevalence with a desired precision of 5% and confidence level of 95%.
N = (1.96)2 (.2)(.8)
(.05)2
N = 246
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Sample size estimation to describe a single population with mean as the outcome measure:
N = Za2 S2
d2
Where:
N – sample size needed
Za – value of Z in normal distribution at desired alpha level
S – standard deviation of the mean of variable being studied
d – maximum tolerable error
Example:
An obstetrician wanted to determine the mean hemoglobin of pregnant patients
consulting at the local health center during their first pre-natal visit. She wants an estimate of at
least within 2 units of the true value of hemoglobin with a confidence of 90%. Previous survey
showed the standard deviation of hemoglobin among pregnant patients during their first pre-
natal visit was 10 grams %.
N = (1.645)2(10)2
(2)2
N = 68
Sample size estimation to compare two populations with rate or proportion as the outcome
measure:
Where:
N – sample size needed per group
Za – value of Z in normal distribution at desired alpha level
P – estimated mean rate or proportion in the two population with the
outcome or (P1/2+P2/2)
Q – estimated mean rate or proportion of the population without the
outcome or (1-P)
P1 – estimated rate or proportion in the first population with the outcome
Q1 – estimated rate or proportion in the first population without the
outcome or (1-P1)
P2 – estimated rate or proportion in the second population with the
outcome
Q2 – estimated rate or proportion in the second population without the
outcome or (1-P2)
d – maximum tolerable error
Example:
A researcher wants to determine the response rates of patients with CHF taking diuretics
alone compared with trandolapril plus diuretic. The investigator want to detect a 20%
improvement in response from the 60% who respond favorably to diuretics alone based on
previous studies. He wants to detect this at the level of significance of 0.05 (1-tailed) and a power
of 90%.
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Computation (exercise)
Sample size estimation to compare two populations with mean as the outcome measure:
N = 2(Za+Zb)2 S2
d2
Where:
N – sample size needed per group
Za – value of Z in normal distribution at desired alpha level
Zb – Valuae of Z in normal distribution at the desired beta level
S – standard deviation of the mean of variable being studied
d – maximum tolerable error
Example:
An investigator wants to determine the effectiveness of a new anti-asthma agent
(Asmalin inhaler) using improvement in PEFR as the outcome. Previous study showed that the
variation in PEFR measurement in the ER was 12 L/min. He wants to detect a difference of at
least 5 L/min between the new drug and the old standard at alpha of 0.05 and a power of 90%.
Computation (exercise)
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WORKSHOP II
1. Based on your research question and objectives, describe in general your planned
methodology.
Inclusion criteria
A. Exclusion criteria
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3. Compute for your sample size.
4. If randomization will be done, describe how you will randomize your subjects.
5. Describe the exposure, treatment or diagnostic tests you plan to observe or compare.
Experimental
Control
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LECTURE IV
METHODOLOGY III: DATA COLLECTION AND
ANALYSIS
DATA COLLECTION
This section will discuss the process of collecting data. The lecture is divided into
subsections that are important in collecting accurate and reliable data.
Investigators should take special care in developing these forms so that data are complete
and accurate. Before designing the form, the investigator should make an outline of all the data
that are to be collected. Each page in the data collection form should contain an identifying mark
for each subject. The data must be organized (modular) for entry into the computer software that
is planned to be used. Modular structure means separating the data collection form into sections
like demography, history, physical examination, laboratory testing, test drugs, other outcomes to
be monitored (quality of life), adverse events etc. Having such ready made data collection forms
improves efficiency and cost of reproduction.
I hope you’ll find helpful the sample data collection forms in Appendix I.
Blinding
Bias can occur at different stages of the research project. It can occur at the time of
assignment to treatment groups. Bias in this case is reduced by randomization. It can also occur
during data collection or observation. Bias in the second situation is reduced by blinding.
Blinding is the process of concealing the treatment or intervention to the patient or investigator.
As much as possible clinical trials should be double blind, meaning both the investigator and the
patient is not aware of the treatment. But if it is impossible as in surgical trials, a single blind
approach or other methods to reduce bias like concealing the intervention to the evaluator or the
statistician can be done. Table 10 enumerates the types of blinding you can use.
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Table 10 Types of Blinding
Open label Both the subject, the investigator and other members of the research team
know the treatment assignment
Single blind Only the subject is not aware of the treatment assignment
Double blind Both the subject and the investigator is not aware of the treatment
assignment
Triple blind This is just an extension or modification of the double blind design, where
aside from the investigator and subject, other persons involved in the
study like the monitoring team, data encoders and statisticians are also
not aware of the treatment assignment
Making a Questionnaire
A questionnaire is a measurement instrument for assessing individual’s attitudes, beliefs,
behavior or attributes. It is important that the researcher should establish first hand what he
wants to measure. Measuring attitude is often difficult because they are very sensitive to
variations in words. Attributes on the other hand is less sensitive to wording variation. Before
constructing your questionnaire be clear about its purpose and the information you want to get.
Make sure that a questionnaire is the best possible method to get that information.
When constructing your questionnaire make sure that your grammar is correct and the
wordings are simple. It should be targeted to the lo est educational level of potential
respondents. Sequence questions into logical order and group them into topics to make the
respondents’ task pleasurable. Keep the questionnaire as short as possible. After constructing the
questionnaire give it to your peers for comments. Pre-test it to a sample of possible respondents.
When changes are made pre-test the revision until you have decided on the trial questionnaire.
If you don’t intend to do these don’t gather your data by means of a questionnaire! Table
11 presents the listing of problems associated with use of questionnaires.
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Table 11 Common Problems in Questionnaire Construction and Use
Lack of attention by the The construction of a good questionnaire requires a high level
researcher of experience and skill and is not to be undertaken lightly
without extensive planning and consultation.
Ethics The respondents’ privacy and dignity should be respected.
Respondent characteristics Factors like age, sex, literacy and educational level may
influence questionnaire results and their reliability.
Response error Response error may arise from failure of memory, motivation,
communication and knowledge. In other words respondents
may not answer correctly and accurately.
Response bias Social desirability bias is present when patients try not to
offend other people or try to respond to behavior questions that
are socially desirable when it may not be the real behavior of
the respondent.
Return rate Low return rates often affect the reliability of the study.
Asking threatening or personal Threatening questions may cause the respondents to be
questions embarrassed and feel uncomfortable. This may also affect the
accuracy of the responses.
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Levels of Measurement
At the start of the study the investigator decides on what outcome to observe and how it
will be measured or recorded.
There four different levels of measurement namely nominal, ordinal, interval and ratio.
Each level needs a different kind of analysis.
1. Nominal data – these are qualitative data which are mutually exclusive and
exhaustive and do not mean hierarchy. Numerals represent category or classification
labels only. For example name, sex (male does not mean being better than female),
address etc.
2. Ordinal data – reflects a rank order among the categories used to measure a variable,
example is economic class (low, middle, upper), scale of severity (none, mild,
moderate, severe, very severe).
3. Interval measures – have more meaning than ordinal measures because the
differences between two categories are known and definite. The intervals between
numbers are equal but not related to true zero. They do not represent true quantity.
For example temperature, calendar years etc.
4. Ratio scale – Numbers represent units with equal intervals measured from true zero.
For example distance, weight, blood pressure etc.
Coding
Coding is the process of assigning numbers to answers or data collected for data entry
and analysis. It must be differentiated from measurement where the purpose is to quantify
characteristics. In pre-coding the data or response is coded before collection. This is applicable if
the responses are known in advance and the questions are close-ended. It is more efficient
because it makes data entry and analysis easier. However it may not be applicable to open-ended
questions. In open-ended and complex questions, post-coding is usually done. In post-coding
numbers are assign to answer categories after they have been collected.
Analysis
Statistical analysis should be planned before data collection. Since the type of data to be
collected or measurement to be done is already planned prior to collection, statistical analysis can
be planned in advance as well. The analysis must be simple as much as possible. Complex
analysis might be impressive but interpretation becomes difficult. Consult a statistician (familiar
with clinical research) for advice on the appropriate statistical analysis for your data. Make use of
existing computer packages to analyze data.
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5. Factor analysis – a method of statistically grouping items which are answered by the
respondents in similar ways
We will not go farther in discussing how to compute for these statistical techniques. Try
to find the algorithm in Figures 2 to 9 helpful in deciding what statistical techniques you will use
in analyzing your data.
Sample Population
Difference Association
Measure the size Testing for Measure of the Testing for Extent
of the difference statistical degree of the statistical association
See Figure 3 significance of association significance of explains
the difference See Figure 4 the association variations
See Figure 5 between groups
See Figure 6
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Testing for statistical significance of association
Nominal Data
Ordinal Data
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Continuous data
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LECTURE V
WRITING THE RESEARCH PROPOSAL
The initial stages and often the most difficult part of the research process is the
development of the research proposal. The proposal describes the purpose of the study, the
importance of the research question, the methodology and justifies the feasibility of the project.
Word Choice
The words chosen should be simple, precise, necessary and familiar. Highly technical
and scientific terms should be used less often and only when necessary i.e. no other familiar
word with the same meaning. Avoid jargon or inventing new words by adding suffixes or
prefixes to familiar words. Use few abbreviations as least as possible.
Sentence Structure
Use simple and direct sentences. This can be done if the core or the message is conveyed
in a simple sentence structure i.e. subject, verb and predicate or completer. The topic should be in
the subject and the action in the verb.
Another common mistake is the piling of nouns into noun cluster or putting too many
ideas in one sentence. A sentence should only talk about one thing at a time. Aim for a mean
sentence length of no more than 20 words per sentence.
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Wrong sentence Suggestions
The children with arteriovenous shunts had The shunts of children arteriovenous shunts were
their shunts opened and heparin injected. opened and heparin was injected
The new drug caused a decrease in heart rate. The new drug decreased heart rate.
Paragraph Structure
The paragraph should convey an organized idea and the continuity of these ideas must
be clear. To do this a paragraph should have a definite structure. It should be started with a topic
sentence followed by a series of logically arranged supporting sentences.
Sample Discussion
(A) There are three different theories put A – topic sentence
forward for the very slow relaxation of catch
muscles of molluscs. (B) One theory holds that B – States first theory
catch is due to some unusual property of
myosin in these muscles that produce a slow
rate of detachment. (C) In this theory C – Explain first theory
paramyosin would have no special role beyond
that of providing the long scaffolding on which
the myosin is positioned as well the mechanical
strength for the large tension developed. (D)
The second theory holds that tension is D – States second theory
developed by actinomysin interaction but is
maintained by paramyosin interactions. (E)
Because the thick filaments are of limited E – Explain second theory
length, interactions have to occur through
fusion of thick filaments. (F) A third theory, to F – States third theory
which I subscribe, pictures a structural change
in paramyosin core affecting the rate of
breaking of myosin-actin links at the filament
surface.
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Outline of the Clinical Research Protocol
This should serve as a guide to the researcher in writing his/her research protocol. The
protocol should contain the following parts:
1. Title of the protocol – contains key words found in the study objectives or the research
question. The title describes the main idea of your project. It serves to orient the reviewer as
to what he or she is about to read. The title should be not so brief that it says nothing or
leaves some things hanging, but it should not be so long that a reviewer has to think hard to
figure out what it means.
2. List of investigators – name of investigators (main investigator first and not the most senior),
their institution and addresses. Limit authors who will actively participate in the study from
planning, conduct of the study, analysis and writing the final paper.
3. Protocol abstract – should not exceed 300 words, single spaced and following standard
structure as shown below:
Objectives – state the main question of the study
Study design – describe design as to the appropriate use of randomization, blinding and
temporal direction
Setting – indicate the study setting (hospital, clinic, community)
Patients/participants – state selection procedures, entry criteria and numbers of
participants entering and completing the study
Interventions – describe the essential features of any intervention including their method
and duration of administration
Main outcome measures – primary outcome measures should be indicated as planned
before data collection begins
Data analysis – state sample size and considerations for its calculation and exact level of
significance. State specific statistical methods to test difference or association
Conclusion – state expected primary conclusions according to study objective along with
the clinical application
4. Introduction
Scientific significance
The introduction should be able to supply background information, rationale
and purpose of the study. It should include a critically appraised and up-to-date review
of literature. Justify that despite the literature cited, there is still a need to answer the
research question and conduct the study.
Research Question
Goals and Objectives
A goal is a general statement that reflects what will be accomplished at the end of
the research. The objectives are similar to the goals of the study but they are more
specific, measurable, attainable, realistic and time bound.
5. Methodology section
Research design or strategy – state the design (randomized controlled trial, cohort or
case-control, etc.), justify choice of the design
Sample population – define target population, demographic area, how they will be
selected, describe randomization if it will be done
Experimental intervention – describe how intervention will be given, describe the process
of blinding if it will be done, how to encourage compliance and other co-intervention
Outcome measurement – specify outcome attributes being measured, how they will be
measured, and ways of minimizing bias in its measurement
Analysis – specify the statistical analysis to be undertaken
Pilot study – describe how and to whom it will be done
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Ethics – emphasize informed consent, confidentiality, insurance policy if any
6. References
7. Time schedule and duties of personnel
8. Budget – indicate source of budget, specify budget for the following:
Personnel
Data handling costs (computer hours)
Materials and supplies
Equipment
Maintenance and operating expenses
Travel
Analysis
Write-up
9. Appendices – include letters of agreement, data collection forms etc.
Methodology
Since you are writing a research protocol the methodology should be written in future
tense. It should be specific and detailed enough that the reader or reviewer will be able to
conduct or replicate the research methodology.
Budget
In preparing a budget you need to know the following, a) policies and requirements of
the agency from which grant funds are being sought, b) the policy and requirements of your
institution, and c) the resources and costs associated with each task or activity of the research
project.
The budget should cover for the following items:
A. Direct costs
1. Personnel (salary, allowances or honoraria)
2. Equipment
3. Supplies
4. Training expenses
5. Travel
6. Alterations and renovations
7. Consortium/Contractual costs
8. Other expenses
B. Indirect costs
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1. Some activities of the project will be shouldered by the host institution such as
building or office maintenance, utilities and other administrative expenses.
2. Rate is usually 40% to 60% of the total direct costs.
C. Institutional commitments
1. Ethical review boards fee
2. Donations
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