Selecting Topic Literature Review Study Design Plan

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Dr. Ravikumar ChodavarapuD.C.H; D.N.B (Pediatrics); F.I.A.P (Nephrology)

Professor of Pediatrics

Kakatiya Medical College

Warangal


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WHY IS RESEARCH NEEDED?

& WHAT TO STUDY (TOPIC)

1. RESEARCH DOER:

Primary Job duty or responsibility, to bring out natures truthsfor the benefit of mankind and living things.

To be able to do research properly.

1. RESEARCH USER:

To understand others research.

To decide whether he can use it (relevance) in his job or activity.

Decisions regarding Health and Disease of Patient and Community.

Teaching health care personnel Planning health care


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What is Evidence Based Medicine?

Use of mathematical estimates of the risk of

benefit and harm,

derived from high-quality research on population

samples,

to inform clinical decision making in the

diagnosis, investigation or management of

individual patients.(Trisha Greenhalgh. How to read a paper The

basics of evidence-based medicine. 3rd Ed.2006.)


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Essential Steps in E.B.M

(Dave Sackett)

1. To convert our information needs into answerable

questions (i.e. to formulate the problem)

2. To track down, with maximum efficiency, the bestevidence with which to answer these questions whichmay come from clinical examination, the diagnostic

laboratory, the published literature or other sources.

3. To appraise the evidence critically to assess its validity(truth) and usefulness (clinical applicability).

4. To implement the results of this appraisal in our clinicalpractice.

5. To evaluate our performance


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RESEARCH STEPS

Research Problem Identification

Questions to be answered

Objectives or Aims of taking up the question

Hypothesis development (for analytical study)

Study design and type

Population definition (Inclusion & Exclusion)

Sample design


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RESEARCH STEPS

Measurements planning

Data collection proforma

Measurements

Recording data

Data Cleaning and readying

Analysis

Observations & Results

Discussion

Conclusions and Suggestions


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Pictorial summary of how research works


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oa

To draw inferences, from findings in the study, about the

nature of the universe around it.

Plan the study to maximize the validity of theinferences at the end of the study.

Internal validity - degree to which the investigatordraws thecorrect conclusion about what actually happened in thestudy.

External validity (also called Generalizability) - degreeto which

these conclusions can be appropriately applied topeople and events outside the study.


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Challenge

To design and implement a study plan with

adequate control over two major threats to

these inferences:

1. Random error (wrong results due to chance).

2. Systematic error (wrong results due to bias).


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CRITERIA FOR GOOD RESEARCH QUESTIONA good research question is described by the acronym FINER (Hulley & Cummings, 1998, p14)

Feasible Adequate Number of SubjectsAdequate Technical expertise

Affordable in time and money

Achievable (Manageable ) in scope

Interesting to the investigator

Novel Confirms or refutes previous findings

Extends previous findings

Provides new findings

Ethical

Relevant To scientific knowledge

To clinical and health policy

To future research directions


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Research Proposal Will Need to Specify

1. The research question;

2. The specific aims of the study;

3. The information to be gained from the studyand its importance;

4. The data to be collected;

5. The approximate time frame for accomplishing thestudy.


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Better Wording of Specific Aim(s)/Objective(s) conveys Statistical

Analysis that is/will be used.

Some examples:

To describe the distributions of risk factors among a cohort ofwomen with breast cancer.

To compare the presentation, evaluation, diagnosis, treatment,and follow-up of. . .

To estimate the incidence of skin cancer among elderly smokersand non-smokers.

To determine whether a significant association exists betweencigarette smoking and pancreatic cancer.

To determine the effect of X on Y once adjusted for Z.

To predict the probability of surviving one-year post-surgery .


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Origin of Clinical Questions

Diagnosis: how to select and interpret diagnostic tests

Prognosis: how to anticipate the patients likely course

Therapy: how to select treatments that do more good than harm

Prevention: how to screen and reduce the risk for disease


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What Research questions can be asked?

Questions about patients symptoms

eg. In a 34 year old man with left-sided chest painwhat is the probability that there is a serioushealth problem and if there is,

will it show up on a resting ECG?

Questions about physical or diagnostic signs

eg. In an otherwise uncomplicated childbirth,

does the presence of meconium in the amnioticfluid indicate significant deterioration in thephysiological state of fetus?


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What Research questions can be asked?

Questions about cost-effectiveness

eg. In order to reduce the suicide rate in a healthdistrict, is it better to employ more consultant

psychiatrists, more community psychiatric nursesor more counselors?

Questions about patients preferences

In women attending a male doctor for vaginalexamination what proportion would like to beoffered a chaperone?


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Research Questions For R.C.T

1. Is Clobazam better than Diazepam inpreventing or decreasing recurrence offebrile fits?

2. Is laparoscopic appendicectomy better thanconventional appendicectomy?

3. Is a verbal advice better than written advicein making the mother correctly implementO.R.T ?


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Research Questions For Cohort Study

Does nimesulide cause hepatotoxicity?

Will prematurity cause delayed motormilestones?

Is well water drinking associated withdiarrhoea in infants?


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Research Questions For Case-Control Study

Does prone sleeping position increase risk of

cot death?

Does cell-phone use increase risk of brain

tumors?


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Research Questions For Cross-sectional surveys

What is the birth weight of babies inAndhraPradesh?

What is the prevalence of LBW?

What are the factors associated with LBW?

Is RDT useful to diagnose malaria?


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STEPS OF RESEARCH

FIRST Settle on the research question (Aims &Objectives)-hypothesis.

SECOND Specify criteria for target andaccessible population.

THIRD Decide appropriate research design

FOURTH Plan measurements of Variables andAvoiding errors systematic & random

FIFTH Design for drawing sample

SIXTHTH Implement as planned without deviations

SEVENTH Analyze data using proper statistical techniques


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Conceptual Framework

(Kleinbaum, Kupper, Morgenstern)

Target population

Actual population

Study population

Selection probabilities


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target population

Consists of the people whom we believe we

are studying.

If, for example, we are studying depression

among teenagers in North Carolina,

then the population consists of all NorthCarolina teenagers.


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Actual Population

Consists of the people in the target population whomight actually contribute data to our study.

For example, if we were collecting our data by

telephone interviews with a random sample ofhouseholds listed in the telephone directory,

then the actual population would consist ofteenagers in households with a listed telephone

number and whose parents would give permissionfor the interview and who would participate ifinvited.


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study population

Consists of the people whose data we have

collected and analyzed. Study population is regarded as an unbiased

random sample from the actual population (KKMframework)

If the sample size were increased to its maximum,then the study population would be the same asthe actual population.

This framework divides up sources of error intorandom error (divergence between the actualpopulation and a particular study population) andsystematic error (divergence between the actualpopulation and the target population).


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Target Population

Clinical and Demographic characteristics define the

Target population.

Specify clinical & demographic characteristics well

suited to research question and defined properly

eg. All teenagers with asthma

All newborn babies with birth weight < 2.5 kg


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Accessible Population

Geographical and Temporal characteristics define theAccessible population.

Subset of target population that is available for study

Representative of target population and easy to study

Eg. Teenagers with asthma living in Warangal, in 2009.


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INTENDED SAMPLE

(Sampling)

Subset of accessible population

Design an approach to selecting the samplerepresentative of accessible population and

easy to do.


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Considerations Examples

Inclusion Criteria

(be specific)

Target Population

Accessible

population

Specifying characteristics that

define populations that arerelevant to question & efficient for

study

Demographic characteristics

Clinical characteristics

Geographical characteristics

Temporal characteristics

A 2 year trial of valparin in

preventing febrile fits

6m-6yr children with febrile fits

No epilepsy, Developmental delay

Children in WGL attending

MGMH

Between 1-1-2010 to 1-12-2010Exclusion Criteria

(be parsimonius)

(that are likely to

interfere with quality

of data or

interpretation offindings)

Meet eligibility criteria but

Likely to be lost for follow-up

Not able to provide reliable data

Ethical considerations

Refusal to participate


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How to Present Research?

Introduction (What, Why, Whom isnecessary?) Problem, Question, Objectives,Hypothesis.

Methods (How do I study?) Design, Sample,Measurements.

Results (What is found?) Observations.

Discussion(Meaning of study?) Inferences,Comparisons, Limitations, Future direction.


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Clinician: Individual Patient

Epidemiologist: Community


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Documents

Selecting Topic Literature Review Study Design Plan