Quality Assurance - Flash Cards
If a 3L spirometer consistently measures 2.5L on 3 quality control measurements, is is precise or accurate?
Precise. All of the measurements are the same. They are not within the margin or error for accuracy, which is 2900 ml to 3100 ml (3.5%) for a 3L spirometer.
if a 3L spirometer measures 2.9L, 3.0.L, and 3.1L on 3 attempts, is it accurate or precise?
Accurate. The mean measurement is 3.0L, which is within the margin of error for a 3L syringe (3.5% or 2900-3100 ml)
At least how many points do you need to measure linearity?
You need at least 3 points along the physiologic range of measurement. A range that is clinically significant.
How would you confirm linearity of a device during a quality control analysis?
Take measurements of the high and low values within a clinically significant range, and a 3rd measurement between the high and low. A total of 3 or more measurements are needed to determine linearity.
What is the difference between repeatability and reproducibility?
Repeatability will produce the same results over a short period of time. the method and location has not changed.
Reproducibility will produce the same results on different machinery, at a different time or place, etc.
The exam states that a biological control will be used to test PFT equipment. What is a biological control?
A person (typically employed with the lab) that has normal lung function and performs test for quality control purposes.
If your correction factor keeps changing, what do you suspect is happening?
There is an issue with your equipment.
What are your 2 primary areas of quality control?
___ ___ standards
___ ___ standards
Equipment performance standards
type of equipment
type of maintenance
type of test signals for checking accuracy and precision
Patient performance standards
technologist ability to operate equipment
instruction and coaching of the patient
patient effort and cooperation
insuring collected data meets acceptable standards
Very Important:
ATS-ERS Standards for Equipment Performance
Vital Capacity:
what is the acceptable range of measurement in liters?
what is the acceptable margin of error in percent (for measurement accuracy)?
what is the flow range?
what is the time of the test in seconds?
Forced Vital Capacity:
what is the acceptable range of measurement in liters?
what is the acceptable margin of error in percent (for measurement accuracy)?
what is the flow range?
what is the time of the test in seconds?
Vital Capacity:
what is the acceptable range of measurement in liters? 0.5-8L
what is the acceptable margin of error in percent? +/- 3%
what is the flow range? up to 14L
what is the time of the test in seconds? 30 seconds
Forced Vital Capacity:
what is the acceptable range of measurement in liters? 0.5-8L
what is the acceptable margin of error in percent? +/- 3%
what is the flow range? up to 14L
what is the time of the test in seconds? 15 seconds
Important:
What is the only difference in the ATS-ERS Standards for the VC and FVC maneuvers?
Time.
VC = 30 seconds FVC = 15 seconds
Important:
According to the ATS-ERS Standards, how many liters should your spirometer be able to collect?
8 Liters
Important:
According to the ATS-ERS Standards, what is the acceptable flow range for the PEF, FEF 25-75, MVV?
What is the acceptable margin of error in percent for the above mentioned flow based maneuvers?
Up to 14 Liters of flow is considered acceptable
+/- 5% margin of error is considered acceptable
You should associate the Westguard rules and Levey-Jennings Charts with what?
Quality control of ABG data
How many standard deviations from the mean are within an acceptable limit for ABG values?
ABG’s are acceptable within 2 standard deviations of the mean.
Explain the difference between a random error and an out of control electrode.
A random error will be indicated by a single result that is outside of the margin of error (typically 2 standard deviations from the mean) on an ABG.
An out of control electrode will be indicated by 2 or more erroneous results reported from the same electrode.
in control random error trend shift out of control
which of the following electrode descriptions should require action from the technologist? what should be done?
No action should be taken for any of the descriptions other than “out of control”.
If an electrode is out of control, it should be checked and/or replaced.