Busy. Please wait.
Log in with Clever

show password
Forgot Password?

Don't have an account?  Sign up 
Sign up using Clever

Username is available taken
show password

Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
Your email address is only used to allow you to reset your password. See our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Didn't know it?
click below
Knew it?
click below
Don't Know
Remaining cards (0)
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Quality Control


Quality Assurance Is the policies, procedures, and activities required to ensure that patient care is delivered appropriately and with high quality.
Quality Assurance In the laboratory requires that test data be accurate and reliable reflecting the true status of the patient so that medical practitioners may rely on the data in making informed patient care decisions.
Quality Control Formal, documented methods of monitoring performance of laboratory personnel, instruments, reagents, products, and equipment to assure accuracy and precision of assay data.
Accuracy: Closeness to the truth.
Precision: Repeatability
Standard A substance that has an exact known value and that, when accurately measured, can produce a solution of an exact concentration.
Standard Used to calibrate new instruments, recalibrate instruments after repair or maintenance, at manufacturer’s recommended intervals, or if a method is out of control
Control A solution that contains the same constituents as those being analyzed in the patient sample.
Control Require a low, normal, and high control. This practice monitors an instrument’s accuracy and precision along a range of assay concentrations.
Controlled Runs Each group of specimens tested (batch) must include controls. If the controls are within the accepted test range, the accuracy of the results obtained from each patient sample in the batch is reasonably assured.
Controlled Runs If, however, the control samples are outside the accepted test range (out of control), the patient test results are invalid and, therefore, test results will not be reported to the physician until the controls are within range.
Duplicate Testing A patient sample from each batch may be randomly selected for a repeat test to monitor precision. It is a prudent practice to repeat all patient sample tests that are abnormal, even if the batch is in control.
Control Charting Quality control chart such as a Levey-Jennings chart.
Mean Arithmetic average.
Standard Deviation Measures how far the data, as a whole, varies from the mean.
In Control (Normal) Variation Data points will vary equally above and below the mean of the control range. Data points will be consistent with the areas under the normal curve. None of the points should be beyond 3 standard deviations of the mean.
Common Causes of Variation Mistakes in measurements, calculations, or documentation. Changes in process. Change of technicians. Changes in supplies and equipment. Defective controls. Improper testing
1-3s: A single point beyond 3 SD indicating a significant change in a process.
4-1s: Four consecutive points on the same side of the mean are beyond 1 SD of the mean.
2-2s: Two consecutive points on the same side of the mean are beyond 2 SD of the mean.
Trend: Seven or more consecutive points traveling in the same direction indicating that a gradual change is occurring.
Shift: Seven or more consecutive points on one side of the mean.
Created by: itsdelis
Popular Medical sets




Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!
"Know" box contains:
Time elapsed:
restart all cards