Do More Screening Tests Lead to Better Health? Choosing Wisely

hi my name is dr. Mike Evans and today

I'm wondering if more is better

specifically if more screening tests are

better I mean it kind of makes sense

it's just a test so it doesn't seem like

there'd be a big downside and it might

pick up something early so to explore

this question let's paint a picture so

you've been going to a family doc or a

GP for many years and when they see you

for an annual checkup they do a whole

bunch of tests I should point out now

that we're talking about screening the

kind of tests we do when you're symptom

free so if you did have symptoms say a

sudden onset of severe fatigue or it

hurts when you pee or you have a strange

lump that is a different story and we'd

be much more likely to order tests to

find out what's going on I'm also making

the assumption your average or low risk

so for example if you've been on a

chronic medication likely to cause

osteoporosis or if you have a strong

family history of a disease we might

take a different course of action I will

link you to some online risk assessment

tools below and at the end so that you

can see where your own risk is at so

let's say your doc always tested your

thyroid and your vitamin D levels a

chest x-ray and ECG tracing for your

heart tested you for osteoporosis maybe

your woman under 21 and you've had a Pap

test or in your 40s and had a

mammography ordered okay now imagine you

moved and switch to a new doctor and she

or he doesn't order any of the screening

tests in fact she doesn't even want you

to come in for an annual opting instead

to invite you for a prevention visit

every few years so you might wonder hmm

was my last doctor better more thorough

great question

so let's look at these tests one at a

time let's start with the one that is

most debated whether low risk women

should have screening mammography to

detect breast cancer in their 40s this

is a hot potato right now and the

subject of much debate something that

the number of lives saved are so small

that all the cost and effort in the high

rate of false alarms investigations

unnecessary biopsies etc are not worth

it for individuals and we should be

investing something with a better return

as a collective others feel that it's


best option we have that it's getting

better and the treating early could get

better treatment options they just feel

better knowing where they are at even

though they know mammograms aren't

perfect for me this last point is key

knowing that the tests aren't perfect we

want them to be black and white this

tells me whether I have or or don't have

the disease but as you learn as we walk

through these tests in fact they're all

about trade-offs while screening tests

can find illness it can also

misdiagnosed people as disease when they

are not or tells people they are fine

when they are not there's more precision

for high-risk people and less precision

for low-risk people we see this ripple

effect with mammograms possible earlier

diagnosis and treatment which is what

most of us picture I think but it's also

important to consider how you would

manage the much higher probability of a

false alarm and possibly triggering

invasive procedures to show in the end

it was nothing to be concerned about

understanding these possible

repercussions pretest is key I should

point out again here that if you do have

a lump or you are at higher risk

don't let this debate delay you from

having discussion with your healthcare

provider what family Doc's will tell you

is that we focus on the testing but it's

it's actually about the relationships I

know that sounds funny but if you have a

good relationship with your doc this

leads to screening that's more

personalized that takes into account

your values the science and your own

unique risk the prevention is partly

about the right screening but the bigger

game in town is you having healthy

behaviors and partnering with you to

make positive change in your life ok

let's look at some of the other tests in

our basket for some tests we simply

don't have the trial showing they are

effective these tests might be ordered

out of habit maybe because they can be

helpful in high-risk people so I would

say thyroid and ECG testing fit here a

2015 review in the annals of internal

medicine show not one single study that

directly assessed benefits and harms of

screening for thyroid dysfunction and

low risk people the United States

Preventive task force or the u.s. PTF

looked at what research data was

available and conclude that routine

screening is not recommended unless

there are symptoms and signs of thyroid

disease or you're pregnant there's a

screening electrocardiogram or ECG of

your heart making

difference.the resting ECG is

problematic as it sends a mixed message

approximately one third to one half of

individuals with a healthy heart have

ECG abnormalities approximately 30% of

individuals with proven heart disease

have a normal resting cg and most

coronary events occur in individuals

without resting ECG abnormalities the

u.s. PTF reviewed the science in 2012

and recommended against screening ECGs

if you are low risk for heart disease

next is measuring vitamin D levels in

the blood which is interesting

especially to us in the northern

latitudes of Canada and again I'm

talking about the average person not

somebody who has malabsorption kidney

disease or other risk factors I suppose

there are three pieces to the vitamin D

puzzle question number one is whether

vitamin D supplementation helps so

that's probably its own whiteboard but

but I would say that it's a one vitamin

left standing with smaller trials

showing benefit for bone heart health

cancer and so on on the other hand we

thought this about many other vitamins

and then larger high-quality randomized

control trial showed they actually

didn't help we are still waiting for

these larger trials of vitamin D second

is a test itself called 25 hydroxy

vitamin D there's some debate about the

test and considerable variation between

labs the ideal level of vitamin D in a

person's body has not been rigorously

established for the population in

general or for specific ethnic groups

finally there's a flipside approach and

that is instead of focus on testing we

focus on lifestyle change like eating

well and getting outside and if we are

at risk say in the winter or if we are

dark skinned or institutionalized

instead of testing we simply take a

vitamin D supplement now let's look at

osteoporosis again we are missing

high-quality research trials to tell us

exactly whom to screen but we also know

that osteoporosis related bone fractures

are common as we age women are at higher

risk and these fractures can cause loss

of Independence function and premature

death so expert groups mostly feel that

the two groups that will benefit from

screening with bone densitometry are one

women and men over 60

five and two people with one or more

risk factors such as having a low impact

fracture low weight we're matured

arthritis and so on see the risk

assessment tool for a longer list your

bone density score dictates how soon you

will have to do follow-up testing but

the key message is that once we have a

snapshot we get a better sense of your

bones if we leave some time in between

testing so for example if you are at low

risk you can actually wait five to ten

years sooner if you have risk factors

but most people can wait two years on to

our next test should you get a chest

x-ray well for people that have smoked a

pack a day for thirty years or more we

have emerging evidence in favor of a low

dose chest CT scan but as far as a chest

x-ray a large randomized trial of about

a hundred and fifty thousand men and

women aged 55 to 74 so that a single

view screening chest x-ray done every

year did not make a difference in the

number of people dying from lung cancer

so finally let's look at pap smears

where we take a swab from a woman's

cervix to check for cancer our story

here has changed

we should say we need to do a PAP

annually on all sexually active woman

now the science tells us that we're

getting many false alarms without

benefits for younger woman

the smarter strategy is to have a Pap

test at age 21 if you're sexually active

and if it's normal then repeat every

three years we stopped at age 70 but

only if there are no problems in the

previous ten years which means three

normal Pap tests okay hopefully you can

see with these various tests is some are

complicated so I'll have no evidence and

some need to be done but only for people

at higher risk or at longer time

intervals speaking of time intervals

even the concept of an annual physical

is not based in science it's not usual

practice outside of North America it's

easier for us to remember every year but

that doesn't mean it's best for our

health for example high risk people get

screened more often but optimal interval

screening for common lab tests like

cholesterol is every three to five years

or every three years for diabetes I

achieved mixed feelings about this I

love the opportunity to just focus on

prevention with my patients but like

most family Doc's I've shifted from

blind annual testing on everybody

towards customs to

jeez to consider your values and your

individual risk factors and encouraging

healthy behaviors like moving more

healthy eating helping people think

better and being opportunistic about

making positive change so as your new

family doc okay I would say so

by less testing she or he is likely

improving your house and applying signs

not only to treatment but to prevention

like a lot of things in life when we

think about it more isn't always better

better communication and knowing

yourself allow you to choose a little

more wisely hope this helps