Research Methodology

Research Methodology

Sohail Bajammal, MBChB, MSc, FRCS(C), PhD(c)[email protected]

Assistant Professor, Umm Al Qura UniversityConsultant Orthopaedic Surgeon, Al-Noor Specialist Hospital

What got me into EBM….

What is a double blind study?

Two orthopaedic surgeonsreading an ECG

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EBM is not new…….

على “ والمقاييس البحث في نرقى ثمالمقدمات انتقاد مع والترتيب التدريجفي غرضنا ونجعل النتائج في والتحفظاستعمال ونتصفحه نستقرئه ما جميع

ما سائر في ونتحرى الهوى اتباع ال العدلمع الميل ال الحق طلب وننتقده نميزه

بن ”اآلراء الحسنالهيثم

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Objectives

• What is research?

• Why do we need to do research?

• What is the difference between research methodology and EBM?

• What are the types of research?

• How to do research?

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What is research?

Systematic investigation towards increasing the sum of knowledge

(Chambers 20th Century Dictionary)

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EconomicLegal

Therapy

Perspectives of Research

Basic Science Social

Diagnosis

Prognosis

Clinical

Health Problem“Trauma”

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Why do we need to do research?“locally”

• Ethnic• Psychosocial• Cultural• Economic

Different

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Research Methodologyvs

Evidence-Based Medicine

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Research

Doing

Using


EBM

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EBM

Clinical Circumstances

Research Evidence

Patients’ Preferences

Clinical Expertise

Haynes et al. BMJ 2002;324:1350

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5As of EBM

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Is this a good question?

What is the best treatment of back pain?

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Asking a good question (PICO)!

• Population• Intervention• Control• Outcome

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Is this a good question?

• In adult patients younger than 50 years old with acute low back pain (< 6 weeks), does bedrest reduce the risk of recurrence of pain within one year compared with physiotherapy?

• P: Adult patients <50yr with acute LBP• I: Bedrest• C: Physiotherapy• O: Recurrence of pain within one year

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5As of EBM

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5S Hierarchy of Evidence

RCTs, Cohort, Case control, Case series

Expert Opinion: Classical Textbooks

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Primary Sources

• Original articles• Using: PubMed, OVID• You have to retrieve and appraise the articles• Levels (strength) of evidence

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Levels of Evidence

http://library.downstate.edu/EBM2/2100.htm

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It’s time consuming

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5S Hierarchy of Evidence

RCTs, Cohort, Case control, Case series

Systematic Reviews

Critically-Appraised Journal Articles & Abstracts

Evidence-Based Guidelines & Textbooks

Computerized Decision Support

Expert Opinion: Classical Textbooks

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To practice EBM, we need all four

Clinical Circumstances

Research Evidence

Patients’ Preferences

Clinical Expertise

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Planning

Conducting

Publishing

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Research Question

Truth in the Universe

Target Population

Phenomena of interest

Study Plan

Truth in the Study

Intended Sample

Intended variables

Actual Study

Findings in the Study

Actual subjects

Actual measurements

From Hulley et al. Designing Clinical Research. LWW

Design Implement

InferInfer

ErrorsErrors

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• Random Errors: mistakes by chance

• Systematic Errors: bias

Errors in Research Methodology

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• Assemble a research team• Ask a good research question• Do a literature search• Choose the proper study design• Determine the sampling design• Get ethical approval

Research Planning

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Research Team

• Research is not a one man/woman show

• You need a team at every step

• Ask a research methodologist & a biostatistician EARLY

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Good Research Question (FINER)

• Feasible

• Interesting

• Novel

• Ethical

• Relevant

PICO

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Sampling

The UniverseStudy

PopulationStudy

Sample

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Bad Sampling

The UniverseStudy PopulationStudy

Sample

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Sample Size

• You need to have enough research participants (patients) to show a difference

• Depends on:– The incidence of the outcomes you are assessing

in each group– The prevalence of the disease

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Sample Size

• Compare applying pressure with no pressure to control active bleeding?

• Compare antibiotics with no antibiotics for bad open fractures to reduce the risk of infection?

• Compare antibiotics with no antibiotics for pneumonia to reduce septic shock?

• Compare LMWH with Unfractionated heparin to reduce the risk of DVT after TKA?

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Types of Research

Quantitative Qualitative

Mixed-Methods

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Quantitative Research

• Descriptive:– Case report– Case series– Cross-sectional

• Analytical:– Observational: cohort studies, case-control– Experimental: randomized trials

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Descriptive Studies

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Case Report

• A descriptive study of one patient

• Detailed profile of a “rare” presentation or treatment

• Helpful in developing hypothesis to be tested later using analytic study

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Case Series

• A descriptive study of multiple patients

• “Rare” phenomenon occurring multiple times

• Detailed profile of patients’ presentation and outcome

• Helpful in developing hypothesis

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Cross-Sectional Studies

• Descriptive “Survey”

• One to one questionnaire, mail, telephone, online

• Attention to details:– Sampling– Construction of the questions– Construction of the responses

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Analytical Studies

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Case-Control Studies

Cases(e.g., Lung Cancer)

Control(e.g., NO Lung

Cancer)

GO BACK IN TIME

GO BACK IN TIME

Ask patientsRead files

Shisha Smokers

NOT Shisha Smokers

Shisha Smokers

NOT Shisha Smokers

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Case-Control Study

Lung Cancer

Yes No

Shisha Smoking

Yes

No

ODDS RATIO

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Problems with Case-Control Studies

• Looking back in time (retrospective)

• Recall bias

• Measurement bias

• You may miss important risk factors

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Prospective Cohort

Shisha Smokers

NOT Shisha Smokers

F/U

F/U

Lung Cancer

No Lung Cancer

Lung Cancer

No Lung Cancer

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Cohort Study

Lung Cancer

Yes No

Shisha Smoking

Yes

No

RELATIVE RISK

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Cohort Study

• Prospective or Retrospective

• Drawbacks:– Large number of patients– Follow them up for long time

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Randomized Controlled Trial (RCT)

Patients with MI RANDOM

Drug A

Drug B

F/U

F/U

Outcomes

Outcomes

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Why RCT is the highest level of evidence?

• Randomization: balance known and unknown prognostic factors

• Blinding:– Patients– Researchers– Outcome assessors

• Aim for complete follow-up

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• Ask for help Research assistants

• Monitor the conduct of the study–No deviation–Patients safety–Complete data

Conducting Research

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• During the planning phase: who will do what?

• Oral & written

• Pick your audience (pick a Journal)

• Write your paper with the Journal you picked in mind

• Don’t give up, you will get rejected

Publishing Research

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Take Home Messages

• Research is not a one man/woman show– You need a team to do good research

• Research is a science– You need to learn how to do it

• Research is like riding a bicycle– You need to practice

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Take Home Messages

• Research needs planning– If you fail to plan, you plan to fail

• Not all of us need to do research– But all of us should practice EBM

• Never ever give up– You will get rejected

GCC EBHC

http://eapps.ngha.med.sa/ebm/

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Objectives

• What is research?• Why do we need to do research?• What is the difference between research and

EBM?• What are the types of research?• How to do research?

[email protected]

Health & Medicine

Research Methodology