Difference between Precise and Accurate or Precision and Accuracy

Definitions :

  • Precision is the degree to which repeated (or reproducible) measurements under unchanged conditions show the same results.
  • Precision is the level of agreement of a particular measurement with itself when it is repeated.
  • Accuracy is the proximity of measurement results to the true value;
  • Accuracy is the fact of being correct and without any mistakes:
Difference between Precise and Accurate or Precision and Accuracy



Assume that Systolic BP is 120 and is measured five times

  • Precise Accurate : 120,120,120,120,120
  • Not precise Accurate : 118,119,120,121,122
  • Precise Not accurate : 130,130,130,130,130
  • Not Precise Not Accurate : 120, 125, 130, 135, 140

Precision : Zero or Low Standard Deviation

Difference between Precise and Accurate or Precision and Accuracy. By Pekaje at English Wikipedia – Transferred from en.wikipedia to Commons., GFDL, https://commons.wikimedia.org/w/index.php?curid=1862863



Why Accreditation of Labs will lead to more sickness / disability / morbidity and more deaths / mortality

Why Accreditation of Labs will lead to more sickness / disability / morbidity and more deaths / mortality

Q1 : What are the benefits of #accredidation of a lab
A1 :
(a) Increased #Precision of Lab Reports
(b) Increased #Accuracy of Lab Reports

Q2 : What are the cost of accredidation of a lab
(a) One Time Cost to Setup the lab increased
(b) Recurrent Cost for each test increased

Difference between
#Precision and #Accuracy
is explained here



Q3 : What happens when the One Time Cost to Setup the lab increased
A3 : There will be fewer labs

Q4 : What will fewer labs lead to
A4 : It leads to
Reduced #availability of a test. You can’t do a test
Reduced #accessibility of a test. You need to travel far to do the test

Q5 : What happens #Recurrent Cost for each test increased
A5 : Test will cost more

Q6 : What does High Cost of a test lead to
A6 : It leads to
You spending more for a test
and as a result
Doing Less Tests than needed

When you #accredidate a lab, you get a More #Precise and More #Accurate Results

But

At the same time
Tests are not #available to many
Tests are not #accessible to many
Tests are not #affordable to many

The number of people doing tests drastically reduces

And
Number of times, a person does a test also drastically comes down

So
Accreditation has #Benefits (Precision and Accuracy)
Accrediation also has #ADVERSE EFFECTS (tests are not done even when it is needed)

Q7 : Which is greater
A7 : The Adverse Effects are greater

Q8 : Can you please show me a study, Cochrane review, Data to prove that Accreditation of Lab is harmful
A8 : There is no study to prove tha parachutes are useful

Q9 : Is this the answer to Q8
A9 : Yes. It is
It means that If you ask data for something which is obvious, you are idiot

Q10 : Are you saying that there should be no quality control for lab test
A10 : No. I support Quality Control. No Doubt. But I need tests first

There is no use in having quality control, improved accuracy, improved precision

If 90 % of population are going to be with no test at all

There are three options here
1. Tests with Accreditation
2. Tests without Accrediation
3. No Test

Between 1 and 2, I will chose 1
But
Between 2 and 3, I will chose 2

Please realise that your attempt at moving from 2 to 1 actually leads to less than 10 percent getting that benefit while 90 percent moves from 2 to 3