Skip to content
  • About
  • Contact
  • Contribute
  • Book
  • Careers
  • Podcast
  • Recommended
  • Speaking
  • All
  • Physician
  • Practice
  • Policy
  • Finance
  • Conditions
  • .edu
  • Patient
  • Meds
  • Tech
  • Social
  • Video
    • All
    • Physician
    • Practice
    • Policy
    • Finance
    • Conditions
    • .edu
    • Patient
    • Meds
    • Tech
    • Social
    • Video
    • About
    • Contact
    • Contribute
    • Book
    • Careers
    • Podcast
    • Recommended
    • Speaking

What does bias when analyzing data have to do with slow lines?

Paul Levy
Education
September 20, 2009
1 Shares
Share
Tweet
Share

Here’s an excerpt from a lovely little book by John D. Barrow called One Hundred Essential Things You Didn’t Know You Didn’t Know; Math Explains the World. This selection has a great lesson about statistical inference. The chapter is entitled, “Why does the other queue always move faster?”

You will have noticed that when you join a queue at the airport or the post office, the other queues always seem to move faster. When the traffic is heavy on the motorway, the other lanes always seem to move faster than the one you choose. Even if you change to one of the others, it still goes slower. In fact, the reason you so often seem to be in the slow queue may not be an illusion. It is a consequence of the fact that on the average you are usually in the slow queue.

The reason is simple. On the average, the slow lines and lanes are the ones that have more people and vehicles in them. So, you are more likely to be in those, rather than in the faster moving ones where fewer people are.

The proviso “on the average” is important here. You won’t invariably be in the slowest line, but on the average, when you consider all the lines that you join, you will be more likely to be on the more crowded lines where most people are.

This type of self-selection is a type of bias that can have far-reaching consequences in science and for the analysis of data, especially if it is unnoticed. Suppose you want to determine if people who attend church regularly are healthier than those who do not. There is a pitfall that you have to avoid. The most unhealthy people will not be able to get to church and so just counting heads in the congregation and noting their state of health will give a spurious result.

When we do science or are confronted with data, the most important question to ask about the results is always whether some bias is present that leads us preferentially to draw one conclusion rather than another from the evidence.

Paul Levy is the former President and CEO of Beth Israel Deaconess Medical Center in Boston and blogs at Not Running a Hospital. He is the author of Goal Play!: Leadership Lessons from the Soccer Field and How a Blog Held Off the Most Powerful Union in America.

Prev

Medical malpractice reform by President Obama and the White House

September 19, 2009 Kevin 12
…
Next

How hospitals should deal with disruptive physician behavior

September 20, 2009 Kevin 12
…

Tagged as: Hospital-Based Medicine, Medical school

Post navigation

< Previous Post
Medical malpractice reform by President Obama and the White House
Next Post >
How hospitals should deal with disruptive physician behavior

More by Paul Levy

  • a desk with keyboard and ipad with the kevinmd logo

    Health care networks: A mistake we will pay for

    Paul Levy
  • How to protect physicians from themselves

    Paul Levy
  • The triple aim has been hijacked by powerful political forces

    Paul Levy

More in Education

  • The role of income in medical school acceptance

    Carter Do
  • Balancing tension and kindness in medical education

    Chloe N. L. Lee, MD, MPH
  • I want to be a doctor who can provide care for women: What states must I rule out for my medical education?

    Nandini Erodula
  • A chance encounter in Chicago: lessons in compassionate medicine

    Emily S. Hagen
  • Business education’s role in preventing physician practice decline

    Curtis G. Graham, MD
  • The impact of assumptions on patient communication in medical training

    Esther Covington
  • Most Popular

  • Past Week

    • Reigniting after burnout: 3 physician stories

      Kim Downey, PT | Physician
    • I’m a doctor, and I almost died during childbirth

      Bayo Curry-Winchell, MD | Physician
    • I’m tired of being a distracted doctor

      Shiv Rao, MD | Tech
    • Inside the grueling life of a surgery intern

      Randall S. Fong, MD | Physician
    • Ketamine for mental health conditions: What every primary care physician needs to know

      Carlene MacMillan, MD & L. Alison McInnes, MD | Meds
    • Physician autonomy and patient interactions in corporate health care

      Michele Luckenbaugh | Conditions
  • Past 6 Months

    • Medical gaslighting: a growing challenge in today’s medical landscape

      Tami Burdick | Conditions
    • Balancing opioid medication in chronic pain

      L. Joseph Parker, MD | Conditions
    • I want to be a doctor who can provide care for women: What states must I rule out for my medical education?

      Nandini Erodula | Education
    • Mourning the silent epidemic: the physician suicide crisis and suggestions for change

      Amna Shabbir, MD | Physician
    • Reigniting after burnout: 3 physician stories

      Kim Downey, PT | Physician
    • 1 in 4 attempt suicide: the persecution of autistic physicians

      Patricia Celan, MD | Physician
  • Recent Posts

    • Physician autonomy and patient interactions in corporate health care

      Michele Luckenbaugh | Conditions
    • PSA screening: What you need to know [PODCAST]

      The Podcast by KevinMD | Podcast
    • Vague criteria can lead to misdiagnosis and prison

      L. Joseph Parker, MD | Conditions
    • U.S. maternal mortality crisis: a deep dive

      Alan Lindemann, MD | Conditions
    • Lively communication in the service industry

      Deepak Gupta, MD | Physician
    • Contemporary weight loss: Unveiling the quest for elusive elixir

      Osmund Agbo, MD | Conditions

Subscribe to KevinMD and never miss a story!

Get free updates delivered free to your inbox.


Find jobs at
Careers by KevinMD.com

Search thousands of physician, PA, NP, and CRNA jobs now.

Learn more

View 2 Comments >

Founded in 2004 by Kevin Pho, MD, KevinMD.com is the web’s leading platform where physicians, advanced practitioners, nurses, medical students, and patients share their insight and tell their stories.

Social

  • Like on Facebook
  • Follow on Twitter
  • Connect on Linkedin
  • Subscribe on Youtube
  • Instagram

CME Spotlights

From MedPage Today

Latest News

  • 'Not Clear If the Juice Is Worth the Squeeze': What We Heard This Week
  • Avoiding Male Doctors Is Not Discrimination. It May Be Risk Aversion.
  • What Is the 'Carrot Tan' Trending on Social Media? A Dermatologist Weighs In
  • Did Gabapentin Improve Post-COVID Olfaction?
  • Fentanyl Death Trends; Food Additives and Heart Disease

Meeting Coverage

  • Loneliness Needs to Be Treated Like Any Other Health Condition, Researcher Suggests
  • Stopping Medical Misinformation Requires Early Detection
  • AI Has an Image Problem in Healthcare, Expert Says
  • Want Better Health Outcomes? Check Out What Other Countries Do
  • ERS Roundup: Cell Transplant Boosts Lung Function in COPD Patients
  • Most Popular

  • Past Week

    • Reigniting after burnout: 3 physician stories

      Kim Downey, PT | Physician
    • I’m a doctor, and I almost died during childbirth

      Bayo Curry-Winchell, MD | Physician
    • I’m tired of being a distracted doctor

      Shiv Rao, MD | Tech
    • Inside the grueling life of a surgery intern

      Randall S. Fong, MD | Physician
    • Ketamine for mental health conditions: What every primary care physician needs to know

      Carlene MacMillan, MD & L. Alison McInnes, MD | Meds
    • Physician autonomy and patient interactions in corporate health care

      Michele Luckenbaugh | Conditions
  • Past 6 Months

    • Medical gaslighting: a growing challenge in today’s medical landscape

      Tami Burdick | Conditions
    • Balancing opioid medication in chronic pain

      L. Joseph Parker, MD | Conditions
    • I want to be a doctor who can provide care for women: What states must I rule out for my medical education?

      Nandini Erodula | Education
    • Mourning the silent epidemic: the physician suicide crisis and suggestions for change

      Amna Shabbir, MD | Physician
    • Reigniting after burnout: 3 physician stories

      Kim Downey, PT | Physician
    • 1 in 4 attempt suicide: the persecution of autistic physicians

      Patricia Celan, MD | Physician
  • Recent Posts

    • Physician autonomy and patient interactions in corporate health care

      Michele Luckenbaugh | Conditions
    • PSA screening: What you need to know [PODCAST]

      The Podcast by KevinMD | Podcast
    • Vague criteria can lead to misdiagnosis and prison

      L. Joseph Parker, MD | Conditions
    • U.S. maternal mortality crisis: a deep dive

      Alan Lindemann, MD | Conditions
    • Lively communication in the service industry

      Deepak Gupta, MD | Physician
    • Contemporary weight loss: Unveiling the quest for elusive elixir

      Osmund Agbo, MD | Conditions

MedPage Today Professional

An Everyday Health Property Medpage Today
  • Terms of Use | Disclaimer
  • Privacy Policy
  • DMCA Policy
All Content © KevinMD, LLC
Site by Outthink Group

What does bias when analyzing data have to do with slow lines?
2 comments

Comments are moderated before they are published. Please read the comment policy.

Loading Comments...