inde 201 pom q1 (fall quarter) 2015 september 28, 2015 practice of medicine quantitative medicine:...

Inde 201POM Q1 (Fall quarter) 2015

September 28, 2015

Practice of MedicineQuantitative Medicine:

Epidemiology & Biostatistics

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Objectives for today

Introductions

Epidemiology in medicine

Course overview, review of the syllabus

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Course Instructor & TAs

Rita Popat, PhD (QM Topic Lead)Clinical Associate Professor

Dept. of Health Research & Policy (HRP)

Division of Epidemiology

Justin Norden, M.Phil. (Course TA)2nd yr medical student

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Introduction to epidemiology

What is epidemiology?

Why should you care?

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What is epidemiology?

What does the word mean?From Greek: epi=upon + demos=people“upon the people”

Epidemic: describes a disease that quickly and severely affects lots of people and then subsides

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John Snow and the cholera epidemic in the 1850s

1813-1858

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What is epidemiology? “Epidemiology is the study of the distribution and

determinants of health-related states or events in populations and the application of this study to control health problems”

- Last JM

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Aims of Epidemiology

1. Determine risk factors of various diseases

2. Identify segments of the population with highest risk to target prevention and intervention opportunities

3. Evaluate the effectiveness of health programs and services in improving health of the population

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What does the array below represent?

1. High blood pressure

2. High blood cholesterol

3. Smoking

4. Obesity

5. Diabetes

6. Physical inactivity

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Risk factors for cardiovascular disease

“The concept of CVD risk factors has become an integral part of the modern medical curriculum and has led to the development of effective treatment and preventive strategies in clinical practice.”

More than 50 million US adults take aspirin regularly for long-term prevention of cardiovascular disease, typically either 81 mg/d or 325 mg/d

?

Acetylsalicylic acid C9H8O4 [2-(acetyloxy)benzoic acid]

Clinical Epidemiology

Clinical epidemiology is the application of epidemiologic principles and methods to problems encountered in clinical medicine.

- Fletcher RH, Fletcher SW, Wagner EH

In “Clinical Epidemiology: the essentials”

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Why should you care?

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Methods in Quantitative medicine

relevant for other foundations of

medical care (population health,

EBP, nutrition, policy…)

Step 1 exam! OK, relevant…but

the reasons that really matter…

- Better advocate for your patient

- Better doctor

Why should you care?Epidemiology/clinical research informs all of the following:

What diseases should you be looking for in patients?

Which patients should you screen for disease?

How are diseases diagnosed?

What conditions cause the disease (risk factors)?

How to prevent disease in your patients?

How to treat diseases in your patients?

What is disease prognosis?

Public health policy/standard of practice.16

Why should you care?

Clinical issues in the practice of medicine

Birth Diagnosis Death

SusceptibilityPreventionScreening and diagnosis

Clinical progressionPrognosis

TreatmentPrognosisPrevention of complications

X X X

Why should you care?

Think about the patient interview you observed on Friday, Sept. 25th

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Why should you care?Epidemiology/clinical research informs all of the following:

What diseases would you be looking for in this patient?

How are diseases diagnosed?

What conditions cause the disease (risk factors)?

Which patients should you screen for disease?

How to prevent disease in your patients?

How to treat diseases in your patients?

What is disease prognosis?

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Source: http://www.health.gov.on.ca/english/providers/pub/cancer/psa/psa_guide/faq.html

Source population

Open repair

Endovascular repair

Outcome +

Outcome -

Outcome +

Outcome -

TIME

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?

Randomize or Observe?

Observational vs. Experimental Studies

Experimental studies – the investigator tries to control the environment in which the hypothesis is tested (the randomized, double-blind clinical trial is the gold standard)

Observational studies – the population is observed without any interference by the investigator

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Why Observational Studies?

Cheaper Faster Can examine long-term effects Hypothesis-generating Sometimes, experimental studies are not ethical (e.g.,

randomizing subjects to smoke) Sometimes, experimental studies are not possible

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Cohort study: Basic design

Source population

Open repair

Endovascular repair

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Outcome +

Outcome +

Outcome -

Outcome -

Endovascular vs Open Repair of Renal Artery Aneurysms: Outcomes of Repair and Long-Term Renal Function. J Am Coll Surg 2013;217:263-269

Prospective Retrospective

Case-control studies

Cohort studies

Case seriesCross-sectional

studiesEcologic studies

Descriptive AnalyticRandomized Clinical

Trials

Experiments

Studies of human subjects

Observational

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Experimental (Intervention) Studies

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Cross-sectional studies

Case-control studies

Cohort studies

RCTs

Evidence for causality

Strong

Weak

Epidemiology and medicine: Why should you care?

Keeping up with the medical literature will make you a better doctor

You risk being misled if you aren’t savvy to study design and statistics

You have to understand risk in order to help patients understand risk

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“Ultimately, treatment decisions are made by patients, not

practitioners and not policy makers. Patients rely on

physicians and other health care professionals to deliver the

most amount of information possible about treatment risks

and benefits. Patients then can consider these issues in the

context of their own individual preferences. Policy makers

Should not interfere with this process unless the evidence

they use to mandate care is substantial.”

JAMA editorial (August 17, 2011—Vol 306, No. 7)

Summary: Applications of epidemiology to medicine

Disease surveillance

Discovering causes

Evaluating diagnostic tests

Evaluating screening programs

Determining the natural history of disease

Finding prognostic factors

Testing treatments

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Objectives for today!

Introductions

Epidemiology in medicine

Course overview, survey, review of the syllabus.

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Primary Course Objectives

To understand the research methods needed to create and synthesize a body of knowledge that can be applied to patient care.

To feel confident in interpreting and implementing existing information related to diseases of humans, patient care, and public health.

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Class survey!

Please complete Qs 1 through 6 (resting pulse) Group assignment (if birthday is an odd number – 15 squats, if

birthday is an even number – 15 arm raises)Redcap link:

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You may open the survey in your web browser by clicking the link below:

If the link above does not work, try copying the link below into your web browser:

POM class survey 2015

https://redcap.stanford.edu/surveys/?s=F38J8HFEYC

Course overview

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Blended course (motivations)9-modules: pre-recorded online series on

epidemiology and biostatistics 3 small-group sessions Reading: Medical Epidemiology, Greenberg et.

al, (editions 2-4 are all acceptable) Quizzes Review sessions and Office hours Integrated POM final exam

Course overview

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IMPORTANT: relevant materials and information for QM can be found on the homepage:

F15-INDE-201-01 Materials / Quantitative Medicine: STUDENTS PLEASE USE THIS

This is all you need to access QM materials

Teacher Learner

Content

Context

Interactions in Education: Reflections

Lecture

Blended

Courtesy Dr. Kelley Skeff

Statistical concepts we will cover include…

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fundamental concepts of measurement scales of measurement distribution, central tendency, variability, probability disease prevalence and incidence health impact (eg, risk differences and ratios) sensitivity, specificity, predictive values

fundamental concepts of hypothesis testing and statistical inference confidence intervals statistical significance and Type I error statistical power and Type II error

Use of statistical tests for different types of data (e.g., comparing means, proportions).

This is not a statistics course!

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If you want to learn more about research

methodology or statistics….

Research methodology

HRP 225**Fall quarter

HRP 226Winter quarter

HRP 251Spring

*http://med.stanford.edu/epidemiology/epiProgram_2006.pdf

Biostatistics

HRP 258**Spring quarter

HRP 261Winter quarter

HRP 262Spring quarter

HRP 259Fall quarter

Clinical Epidemiology*

** core requirements for clinical research scholarly concentration

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Course requirements

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Satisfactory completion of the quizzes and the final exam

Office hours Rita Popat Wednesday 1:30-2:20 pm Location: LKSC 203/4 Tel: 650-498-5206 E-mail: rpopat@stanford.edu

Justin Norden

Office hour: Tuesday 12:30-1:20 pm,

Location: LKSC Cafe

E-mail:     jnorden@stanford.edu               

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PLEASE CONTACT US!