Concepts of Measurement: Validity & Reliability

Question 1

Reliability

Answer 1

Does it measure something consistently?

Question 2

Reliability

Answer 2

How do I know that the test, the scale, the instrument works every time I use it?

Question 3

Reliability

Answer 3

Represents the consistency of measure obtained

Question 4

Validity

Answer 4

Does it measure what it is supposed to?

Question 5

Validity

Answer 5

How do I know that the test, scale or instrument I use measures what it is supposed to?

Question 6

Validity

Answer 6

The extent to which an instrument reflects the true measure being observed (accuracy)

Question 7

Error in Physiological Assessment

Answer 7

Environment, User, Subject, Machine, Interpretation

Question 8

Error in Physiological Assessment - Environment

Answer 8

Temperature - can affect the validity of the reading

Question 9

Error in Physiological Assessment - User

Answer 9

A procedural error or interrater reliability

Question 10

Error in Physiological Assessment - Subject

Answer 10

Needs to correlate to what the patient is feeling. If a patient is feeling anxious when having their BP taken their heart rate will automatically increase. This will affect the validity of their measurements.

Question 11

Error in Physiological Assessment - Machine

Answer 11

Accuracy, Selectivity, Precision, Sensitivity

Question 12

Error in Physiological Assessment - Subject

Answer 12

Patient or phenomena

Question 13

Accuracy

Answer 13

Is the machine giving the result it should provide - is it reliable? Is it valid?

Question 14

Selectivity

Answer 14

Is the correct equipment being used? The machinery is intended for a specific type of finding.

Question 15

Precision

Answer 15

It provides results that are reliable and valid

Question 16

Sensitivity

Answer 16

That the machine can pick up the deterioration of the patient, provides the actual reading, alerts of any alterations within findings.

Question 17

Interpretation

Answer 17

How are the results interpreted? The nurse needs to have the right understanding and knowledge of the findings attained.

Question 18

Impact of the environment on equipment validity and reliability

Answer 18

If the patient has cold clammy hands, this may not provide an accurate reading. This also includes if the fingers are moving and don’t remain still.

Question 19

BP Validation

Answer 19

Checking that the pressure gauge of the monitor against a reference number

Question 20

BP Calibration

Answer 20

The process of comparing the pressure gauge against a known accurate reference, and adjusting the pressure to have the same readings.