Quantitative Data Analysis and Interpretation

Question 1

Explain what goodness of fit is.

Answer 1

it looks at how well the pieces fit together; examines

purpose, design, research question(s) or hypothesis, conceptual and operational definitions, data collection method

Question 2

How is data consistency achieved?

Answer 2

by measuring the data in the same manner for each subject

Question 3

What must be developed in order to ensure intervention fidelity?

Answer 3

A data collection protocol that ensures data is measured in the same manner for each subject

assistants and co-investigators need to be trained into it to ensure consistency

Question 4

What does Data Consistency ensure?

Answer 4

Interrator Reliability; consistency of observations

Question 5

What is Interrater Reliability and how is it expressed?

Answer 5

it is the consistency of observations

Reflected as a coefficient kappa (Cohen’s Kappa)

Question 6

What is intervention fidelity?

Answer 6

consistency in data collection

Question 7

List some data collection strategies

Answer 7

Physiological or biological measurements

observational methods

interviews (open or closed ended)

Questionaires

Records or available data
ex hospital records, historical documents, audio or video tapes

Question 8

What are the four important things that must be present in observational methods?

Answer 8

1) observations undertaken are consistent with the study’s objectives and theoretical framework
2) Standardized and systematic plan for observation and recording of data
3) training data collectors
4) All observations checkeed and controlled

Question 9

give some examples of measurement tools

Answer 9

pain scales
CAM scores
Intelligence testing
Anxiety scales

Question 10

What is the term that means evaluating the measurement tool?

Answer 10

Psychometrics

Question 11

What does reliability of a measurement tool mean?

Answer 11

it means the CONSISTENCY with which the instrument measures the concept of interest

Question 12

What are the three aspects of reliability of a measurement tool?

Answer 12

STABILITY

HOMOGENEITY / INTERNAL CONSISTENCY

EQUIVALENCE / INTERRATER RELIABILITY; Cohen’s kappa

Question 13

Describe what stability of a measurement tool means.

Answer 13

it is the test-retest reliability.

ie. how consistent it remains over time

Question 14

Describe what homogeneity/internal consistency is

Answer 14

it is the extent to which items within a scale reflect or measure the same concept

Question 15

What is used to measure homogeneity/internal consistency and what is the acceptable value?

Answer 15

Chronbach’s alpha

want 0.80 or greater
0.70 might be acceptable if tool was designed exclusively for the study

Question 16

What is another term for interrater reliability?

Answer 16

equivalence

Question 17

What are the two concepts that psychometrics examine?

Answer 17

Reliability and Validity

Question 18

Describe what control is

Answer 18

it is measures that the researchers take to make the conditions uniform to avoid EXTRANEOUS variables from influencing the dependent variable

Question 19

Describe how control of the treatment might be obtained.

Answer 19

Make a detailed description of the treatments

Use strategies to ensure consistency in implementation;
Same nurse does intervention, uses same equipment, at the same time, in the sae sequence

Question 20

What is the impact of variations in treatment on the study?

Answer 20

it reduces effect size and internal validity

effect size; strength of the phenomenon

Question 21

What are 4 strategies that can be implemented to control the extraneous variables?

Answer 21

1) homogenous sampling
2) data consistency
3) Random selection and randomization
4) Manipulation of the independent variable

Question 22

Describe what validity means in terms of psychometrics

Answer 22

the extent to which an instrument actually measures or reflects the abstract construct

ie accuracy

Question 23

How can validity of a measurement tool be established (psychometrics)

Answer 23

through expert opinions / panels

and through comparison to other scales or events

Question 24

What is internal validity of a study

Answer 24

the extent to which the study findings are true rather than the result of extraneous variables

Factors from WITHIN the study design

Question 25

What is external validity of a study?

Answer 25

the extent to which study findings can be generalized beyond the sample used in the study

Can you apply findings OUTSIDE the study

Question 26

What are 6 things that can threat internal validity. Describe each

Answer 26

1) maturation: developmental changes that occur over time
2) history: events that occur outside of the study
3) Mortality: unequal rates of attrition
4) Instrumentations: any changes
5) Testing: effect of testing and retesting
6) Selection bias: may have unmeasured attributes that create differences in groups

Question 27

What are some threats to external vailidity (3)

Answer 27

1) Selection Effects: who is in the study
2) Reactive Effects: Hawthorne effect (how behaviour changes as a result of awareness of observation)
3) Measurement Effects

Question 28

What is the Rosenthal Effect (also known as the Pygmalion Effect)?

Answer 28

It is a phenomenon where behaviours change based on researcher’s expectations

Question 29

What can be done to reduce the bias from the Rosenthal Effect?

Answer 29

Double blind experiment

Question 30

Describe what the Halo Effect is.

Answer 30

It is a phenomenon where a participant can score better based on past scores/assessments

ex: a student who gets good grades might get a good grade on a substandard work based on past performance.