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Show Me the Data: Becoming an Expert on Yourself: Talithia Williams at TEDxClaremontColleges

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    As a kid I always loved information
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    that I could get from data
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    and the stories that could be told
    with numbers.
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    I remember, growing up,
    I'd be frustrated
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    at how my own parents
    would lie to me using numbers.
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    "Talithia, if I've told you once
    I've told you a thousand times."
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    No dad, you've only told me 17 times
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    and twice it wasn't my fault.
    (Laughter)
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    I think that is one of the reasons
    I got a Ph.D. in statistics.
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    I always wanted to know,
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    what are people trying to hide
    with numbers?
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    As a statistician,
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    I want people to show me the data
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    so I can decide for myself.
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    Donald and I were pregnant
    with our third child
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    and we were at about 41 and a half weeks,
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    what some of you may refer to
    as being overdue.
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    Statisticians, we call that
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    being within the 95 percent
    confidence interval.
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    (Laughter)
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    And at this point in the process
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    we had to come in every couple of days
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    to do a stress test on the baby,
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    and this is just routine,
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    it tests whether or not the baby
    is feeling any type of undue stress.
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    And you are rarely, if ever,
    seen by your actual doctor,
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    just whoever happens to be
    working at the hospital that day.
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    So we go in for a stress test
    and after 20 minutes
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    the doctor comes out and he says,
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    "Your baby is under stress,
    we need to induce you."
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    Now, as a statistician,
    what's my response?
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    Show me the data!
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    So then he proceeds to tell us
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    the baby's heart rate trace
    went from 18 minutes,
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    the baby's heart rate was
    in the normal zone
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    and for two minutes
    it was in what appeared to be
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    my heart rate zone and I said,
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    "Is it possible that maybe
    this was my heart rate?
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    I was moving around a little bit,
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    it's hard to lay still on your back,
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    41 weeks pregnant for 20 minutes.
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    Maybe it was shifting around."
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    He said, "Well, we don't want
    to take any chances."
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    I said okay.
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    I said, "What if I was at 36 weeks
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    with this same data?
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    Would your decision be to induce?"
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    "Well, no, I would wait
    until you were at least
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    38 weeks, but you are almost 42,
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    there is no reason
    to leave that baby inside,
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    let's get you a room."
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    I said,
    "Well, why don't we just do it again?
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    We can collect more data.
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    I can try to be really still
    for 20 minutes.
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    We can average the two and see
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    what that means.
    (Laughter)
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    And he goes,
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    "Ma'am, I just don't want you
    to have a miscarriage."
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    That makes three of us.
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    And then he says,
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    "Your chances of having
    a miscarriage double
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    when you go past your due date.
    Let's get you a room."
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    Wow. So now as a statistician,
    what's my response?
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    Show me the data!
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    Dude, you're talking chances,
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    I do chances all day long,
    tell me all about chances.
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    Let's talk chances.
    (Laughter)
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    Let's talk chances.
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    So I say, "Okay, great.
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    Do I go from a 30-percent
    chance to a 60-percent chance?
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    Where are we here
    with this miscarriage thing?
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    And he goes, "Not quite, but it doubles,
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    and we really just want
    what's best for the baby."
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    Undaunted, I try a different angle.
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    I said, "Okay, out of 1,000
    full-term pregnant women,
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    how many of them are going to miscarry
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    just before their due date?
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    And then he looks at me
    and looks at Donald,
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    and he goes, about one in 1,000.
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    I said, "Okay, so of those 1,000 women,
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    how many are going to miscarry
    just after their due date?"
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    "About two."
    (Laughter)
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    I said, "Okay, so you are telling me
    that my chances
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    go from a 0.1-percent chance
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    to a 0.2-percent chance."
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    Okay, so at this point
    the data is not convincing us
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    that we need to be induced,
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    and so then we proceed
    to have a conversation
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    about how inductions lead to a higher rate
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    of Cesarean sections, and if at all
    possible we'd like to avoid that.
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    And then I said,
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    "And I really don't think
    my due date is accurate."
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    (Laughter)
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    And so this really stunned him
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    and he looked sort of puzzled
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    and I said, "You may not know this,
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    but pregnancy due dates are calculated
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    assuming that you have
    a standard 28-day cycle,
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    and my cycle ranges —
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    sometimes it's 27,
    sometimes it's up to 38 —
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    and I have been collecting
    the data to prove it.
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    (Laughter)
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    And so we ended up leaving the hospital
    that day without being induced.
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    We actually had to sign a waiver
    to walk out of the hospital.
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    And I'm not advocating
    that you not listen to your doctors,
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    because even with our first child,
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    we were induced at 38 weeks;
    cervical fluid was low.
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    I'm not anti-medical intervention.
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    But why were confident to leave that day?
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    Well, we had data
    that told a different story.
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    We had been collecting data for six years.
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    I had this temperature data,
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    and it told a different story.
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    In fact, we could probably pretty
    accurately estimate conception.
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    Yeah, that's a story you want to tell
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    at your kid's wedding reception.
    (Laughter)
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    I remember like it was yesterday.
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    My temperature was a sizzling 97.8 degrees
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    as I stared into your father's eyes.
    (Laughter)
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    Oh, yeah. Twenty-two more years,
    we're telling that story.
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    But we were confident to leave
    because we had been collecting data.
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    Now, what does that data look like?
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    Here's a standard chart
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    of a woman's waking body temperature
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    during the course of a cycle.
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    So from the beginning
    of the menstrual cycle
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    till the beginning of the next.
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    You'll see that the temperature
    is not random.
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    Clearly there is a low pattern
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    at the beginning of her cycle
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    and then you see this jump
    and then a higher set of temperatures
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    at the end of her cycle.
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    So what's happening here?
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    What is that data telling you?
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    Well, ladies,
    at the beginning of our cycle,
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    the hormone estrogen
    is dominant and that estrogen
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    causes a suppression
    of your body temperature.
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    And at ovulation,
    your body releases an egg
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    and progesterone takes over,
    pro-gestation.
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    And so your body heats up in anticipation
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    of housing this new little fertilized egg.
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    So why this temperature jump?
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    Well, think about
    when a bird sits on her eggs.
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    Why is she sitting on them?
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    She wants to keep them warm,
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    protect them and keep them warm.
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    Ladies, this is exactly
    what our bodies do every month,
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    they heat up in anticipation
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    of keeping a new little life warm.
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    And if nothing happens,
    if you are not pregnant,
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    then estrogen takes back over
    and that cycle starts all over again.
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    But if you do get pregnant, sometimes you
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    actually see another shift
    in your temperatures
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    and it stays elevated
    for those whole nine months.
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    That's why you see those pregnant women
    just sweating and hot,
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    because their temperatures are high.
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    Here's a chart that we had
    about three or four years ago.
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    We were really very excited
    about this chart.
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    You'll see the low temperature level
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    and then a shift and for about five days,
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    that's about the time
    it takes for the egg to travel
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    down the fallopian tube and implant,
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    and then you see those temperatures
    start to go up a little bit.
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    And in fact, we had
    a second temperature shift,
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    confirmed with a pregnancy test
    that were indeed pregnant
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    with our first child, very exciting.
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    Until a couple of days later
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    I saw some spotting
    and then I noticed heavy blood flow,
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    and we had in fact
    had an early stage miscarriage.
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    Had I not been taking my temperature
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    I really would have just thought
    my period was late that month,
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    but we actually had data to show
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    that we had miscarried this baby,
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    and even though this data
    revealed a really
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    unfortunate event in our lives,
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    it was information
    that we could then take to our doctor.
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    So if there was a fertility issue
    or some problem,
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    I had data to show:
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    Look, we got pregnant,
    our temperature shifted,
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    we somehow lost this baby.
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    What is it that we can do
    to help prevent this problem?
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    And it's not just about temperatures
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    and it's not just about fertility;
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    we can use data about our bodies
    to tell us a lot of things.
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    For instance, did you know that taking
    your temperature can tell you a lot
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    about the condition of your thyroid?
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    So, your thyroid works a lot like
    the thermostat in your house.
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    There is an optimal temperature
    that you want in your house;
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    you set your thermostat.
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    When it gets too cold in the house,
    your thermostat kicks in
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    and says, "Hey, we need
    to blow some heat around."
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    Or if it gets too hot,
    your thermostat registers,
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    "Turn the A.C. on. Cool us off."
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    That's exactly how your thyroid works
    in your body.
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    Your thyroid tries to keep
    an optimal temperature
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    for your body.
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    If it gets too cold, your thyroid
    says, "Hey, we need to heat up."
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    If it gets too hot,
    your thyroid cools you down.
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    But what happens when your
    thyroid is not functioning well?
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    When it doesn't function, then it shows up
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    in your body temperatures,
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    they tend to be lower than normal
    or very erratic.
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    And so by collecting this data
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    you can find out information
    about your thyroid.
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    Now, what is it, if you had a thyroid
    problem and you went to the doctor,
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    your doctor would actually test
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    the amount of thyroid stimulating hormone
    in your blood.
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    Fine. But the problem with that test is
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    it doesn't tell you how active
    the hormone is in your body.
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    So you might have
    a lot of hormone present,
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    but it might not be
    actively working to regulate
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    your body temperature.
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    So just by collecting
    your temperature every day,
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    you get information
    about the condition of your thyroid.
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    So, what if you don't want to take
    your temperature every day?
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    I advocate that you do,
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    but there are tons
    of other things you could take.
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    You could take your blood pressure,
    you could take your weight —
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    yeah, who's excited about
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    taking their weight every day?
    (Laughter)
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    Early on in our marriage,
    Donald had a stuffy nose
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    and he had been taking
    a slew of medications
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    to try to relieve his stuffy nose,
    to no avail.
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    And so, that night he comes
    and he wakes me up and he says,
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    "Honey, I can't breath out of my nose."
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    And I roll over and I look, and I said,
    "Well, can you breath out of your mouth?"
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    (Laughter)
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    And he goes,
    "Yes, but I can't breath out of my nose!"
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    And so like any good wife, I rush him
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    to the emergency room
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    at 2 o'clock in the morning.
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    And the whole time
    I'm driving and I'm thinking,
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    you can't die on me now.
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    We just got married,
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    people will think I killed you!
    (Laughter)
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    And so, we get to the emergency room,
    and the nurse sees us,
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    and he can't breath out of his nose,
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    and so she brings us to the back
    and the doctor says,
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    "What seems to be the problem?"
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    and he goes,
    "I can't breath out of my nose."
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    And he said,
    "You can't breath out of your nose?
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    No, but he can breath
    out of his mouth. (Laughter)
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    He takes a step back
    and he looks at both of us
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    and he says,
    "Sir, I think I know the problem.
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    You're having a heart attack.
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    I'm going to order an EKG and a CAT scan
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    for you immediately."
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    And we are thinking, no, no, no.
    It's not a heart attack.
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    He can breathe, just out of his mouth.
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    No, no, no, no, no.
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    And so we go back and forth
    with this doctor
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    because we think
    this is the incorrect diagnosis,
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    and he's like, "No really, it'll be fine,
    just calm down."
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    And I'm thinking, how do you calm down?
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    But I don't think
    he's having a heart attack.
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    And so fortunately for us, this doctor
    was at the end of the shift.
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    So this new doctor comes in,
    he sees us clearly distraught,
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    with a husband who can't breath
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    out of his nose.
    (Laughter)
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    And he starts asking us questions.
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    He says, "Well, do you two exercise?"
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    We ride our bikes,
    we go to the gym occasionally.
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    (Laughter)
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    We move around.
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    And he says, "What were you doing
    just before you came here?"
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    I'm thinking, I was sleeping, honestly.
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    But okay,
    what was Donald doing just before?
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    So Donald goes into this slew
    of medications he was taking.
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    He lists, "I took this decongestant
    and then I took this nasal spray,"
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    and then all of a sudden
    a lightbulb goes off and he says,
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    "Oh! You should never mix this
    decongestant with this nasal spray.
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    Clogs you up every time.
    Here, take this one instead."
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    He gives us a prescription.
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    We're looking at each other,
    and I looked at the doctor,
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    and I said,
    "Why is it that it seems like you
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    were able to accurately diagnose
    his condition,
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    but this previous doctor wanted to order
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    an EKG and a CAT scan?"
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    And he looks at us and says,
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    "Well, when a 350-pound man walks in the
    emergency room and says he can't breath,
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    you assume he's having a heart attack
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    and you ask questions later."
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    Now, emergency room doctors
    are trained to make decisions quickly,
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    but not always accurately.
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    And so had we had some information
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    about our heart health to share with him,
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    maybe we would have gotten a better
    diagnosis the first time.
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    I want you to consider
    the following chart,
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    of systolic blood pressure measurements
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    from October 2010 to July 2012.
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    You'll see that these measurements start
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    in the prehypertension/hypertension zone,
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    but over about the course
    of a year and a half
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    they move into the normal zone.
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    This is about the heart rate
    of a healthy 16-year-old.
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    What story is this data telling you?
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    Obviously it's the data from someone
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    who's made a drastic transformation,
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    and fortunately for us,
    that person happens to be here today.
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    So that 350-pound guy that walked
    into the emergency room with me
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    is now an even sexier and healthier
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    225-pound guy,
    and that's his blood pressure trace.
  • 15:10 - 15:13
    So over the course of that year and a half
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    Donald's eating changed
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    and our exercise regimen changed,
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    and his heart rate responded,
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    his blood pressure responded
    to that change
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    that he made in his body.
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    So what's the take-home message
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    that I want you to leave with today?
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    By taking ownership of your data
    just like we've done,
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    just by taking this daily measurements
    about yourself,
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    you become the expert on your body.
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    You become the authority.
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    It's not hard to do.
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    You don't have to have
    a Ph.D. in statistics
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    to be an expert in yourself.
  • 15:48 - 15:50
    You don't have to have a medical degree
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    to be your body's expert.
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    Medical doctors,
    they're experts on the population,
  • 15:55 - 15:59
    but you are the expert on yourself.
  • 15:59 - 16:00
    And so when two of you come together,
  • 16:00 - 16:02
    when two experts come together,
  • 16:02 - 16:05
    the two of you are able
    to make a better decision
  • 16:05 - 16:07
    than just your doctor alone.
  • 16:07 - 16:10
    Now that you understand
    the power of information
  • 16:10 - 16:13
    that you can get through
    personal data collection,
  • 16:13 - 16:16
    I'd like you all to stand
    and raise your right hand.
  • 16:16 - 16:18
    (Laughter)
  • 16:18 - 16:20
    Yes, get it up.
  • 16:24 - 16:30
    I challenge you to take ownership
    of your data.
  • 16:31 - 16:34
    And today, I hereby confer upon you
  • 16:35 - 16:38
    a TEDx associate's degree
    in elementary statistics
  • 16:38 - 16:43
    with a concentration
    in time-dependent data analysis
  • 16:44 - 16:48
    with all the rights and privileges
    appertaining thereto.
  • 16:48 - 16:51
    And so the next time
    you are in your doctor's office,
  • 16:51 - 16:54
    as newly inducted statisticians,
  • 16:54 - 16:57
    what should always be your response?
  • 16:57 - 17:00
    Audience: Show me the data!
    Talithia Williams: I can't hear you!
  • 17:00 - 17:01
    Audience: Show me the data!
  • 17:01 - 17:02
    TW: One more time!
  • 17:02 - 17:04
    Audience: Show me the data!
  • 17:04 - 17:05
    TW: Show me the data.
  • 17:05 - 17:06
    Thank you.
  • 17:06 - 17:08
    (Applause)
Title:
Show Me the Data: Becoming an Expert on Yourself: Talithia Williams at TEDxClaremontColleges
Description:

Dr. Talithia Williams' talk explores how each of us can begin to collect data about ourselves that can provide insight into our personal health.

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Video Language:
English
Team:
closed TED
Project:
TEDxTalks
Duration:
17:10

English subtitles

Revisions