1. Measurement & Data Collection
The Pennsylvania state university college of nursing
Nursing 200w

2. What are the concepts of measurement theory?
Directness
Error
Level
Reliability
Validity

3. What is directness of measurement?
Direct measures
Indirect measures
Concrete measures such as:
Oxygen saturation
Temperature
Weight
Blood pressure
Blood glucose
Abstract measures such as:
Pain
Depression
Anxiety
Self-care
Self-esteem

4. What is a measurement error?
Error is the difference between the true measure and what is actually measured
SYSTEMATIC ERROR: The variation in measurement in the same direction (e.g., a blood pressure cuff that consistently measures 5 mmHg above the true measure on every person, every time)
RANDOM ERROR: Differences in measurements without a pattern (e.g., a blood pressure cuff measuring 15 mmHg less than the true measure due to a mechanical issue on a patient before it is fixed)

5. What are the levels of measurement?
Nominal
Ordinal
Interval
Ratio

6. Nominal Lowest level of measurement Ranking not possible
Categories are exclusive of one another and exhaustive
Example:
Political Affiliation
1= Republican
2= Democrat
3= Independent
4= Other

7. Ordinal Exclusive and exhaustive categories
Order or ranking imposed on categories
Intervals between the categories may not always be equal
Example:
ADL Scale
1= Completely dependent
2= Needs assistance
3= Completely independent

8. Interval Numerical distance between intervals NO absolute zero
Often used in math and higher level statistics
Example (not many!):
Temperature as measured in Fahrenheit or Celsius
Likert-scale scores

9. Ratio Considered highest level of measurement Continuum of values
Absolute zero
Example:
Weight
Percentile test scores

10. What are reliability and validity?
Reliability is similar to the concept of consistency
Validity is accuracy or precision of a measure

11. How would you critically appraise reliability in a research study?
What reliability information is provided?
Does the author include reports of the validity of the instrument from previous studies?
Did the author perform pilot studies to examine the validity of the instrument?
Did the researcher report use of data from the present study to examine instrument validity in the discussion section of the report?

12. How would you critically appraise methods of measurement?
Were the measurement strategies clearly identified and described?
What level of measurement was achieved by each instrument?
Was the reliability of each measurement method adequate?
Was the validity of each measurement method adequate?
If physiological instruments were used, were they accurate and precise?

13. What types of measurements strategies are used in nursing?
Physiological measurements
Observational measurements
Interviews
Focus groups

14. What are examples of physiological measures?
Physical measurement methods
ECG BP
I&O
Microbiological measurement methods
Cultures
Sensitivities
Smears

15. What are observational measures?
Unstructured observations
Subjective observation
Structured observations
Objective observation using:
Category systems
Checklists
Rating scales

16. How would you critically appraise observational measurements?
Is the object of observation clearly identified and defined?
Is interrater reliability described?
Are the techniques for recording observations described?

17. How is self-reported data collected?
With this type of strategy, the subjects or participants provide data
Can be done using the following strategies:
Interviews
Questionnaires or surveys
Scales

18. What do unstructured interviews look like?
Unstructured interview questions may look like these:
Tell me about...
What has been your experience with...
What was it like to hear you have cancer?

19. What are structured interviews?
Structured interviews include:
Describing interview questions
Pretesting the interview protocol
Training the interviewers
Preparing for an interview
Probing
Recording interview data

20. How would you critically appraise interview methods?
Do the interview questions address concerns expressed in the research problem?
Are the interview questions relevant for the research purpose and objectives, questions, or hypotheses?
Does the design of the questions tend to bias subjects’ responses?
Does the sequence of questions tend to bias subjects’ responses?

21. What do questionnaires or surveys look like?
Many factors* need to be considered in developing questionnaires or surveys!
These include items like language, reading level, length, clarity, etc.
Questionnaires may be distributed or administered:
In-person or by phone
Internet or (e.g., Survey Monkey)
Mail
*This is why it is generally recommended that a researcher utilize an existing tool, if possible!

22. What are the reasons for using (or not using) questionnaires or surveys?
advantages
disadvantages
Large samples
Affordable
Efficient
High bias
May have very low response rates impacting sample representativeness of population of interest

23. What are some types of scales?
Rating scales
The Likert scale
Visual analog scales

24. What questions should you consider when critically appraising the data collection process?
Were the recruitment and selection of study participants or subjects clearly described and appropriate?
Were the data collected in a consistent way?
Were the study controls maintained as indicated by the design? Did the design include an intervention that was consistently implemented?
Was the integrity of the study protected, and how were any problems resolved?
Did the researchers obtain data from an existing database? If so, did the data obtained address the study problem and objectives, questions, or hypotheses? Was the reliability and validity of the database addressed in the research report?

25. Questions? Comments?
The end!