Semester One Final Exam Flashcards
What are ways to maximize reliability
- Standardize measurement methods
- Train and test observers
- Refine and Automate Instruments
- Blind to reduce differential bias across groups
What are ways to maximize validity
- Random Assignment
- Use of Control Groups
- Blinding (can prevent compensatory reactions and imitation of treatment)
- Selection of Homogeneous Subjects
- Blocking (build extraneous attribute variables into design by using them as independent variables)
- Matching (Age, Sex, Etc)
- Using subjects as their own control
- Analysis of Covariance
What are sources of knowledge
- Tradition
- Authority
- Trial and Error
- Logical Reasoning
- Scientific Method
Define Inductive and Deductive reasoning
- Inductive Reasoning - Specific to general
- Deductive Reasoning - General to specific
What are the four steps for identifying the research question
- From a problem area, identify the research problem
- Justification for the research problem
- Develop the research question
- State hypotheses
Why should theories be Economical or “Parsimonious” as well as important
- Economical (Parsimonious) – Explain the most with the fewest variables. If two variables explain 75% of the problem, but adding 5 more variables only explains an additional 3%, it would be parsimonious to stick with just the initial two.
- Important - “so what”. Should be significant for those who will use it
What are some ways we can ensure protection of human rights
- Beneficence: the obligation to attend to the well-being of individuals
- Justice: refers to fairness in the research process; fair selection of subjects to equally distribute the benefits and burdens
- Use of control groups when effective therapeutic methods exist may present problem
What are continuous variables
- Can take on any value along a continuum within a defined range
- Infinite fractional values can occur
- Accuracy of measurement relies upon precision of measuring tool
What are Discrete variables
- Described only in whole units
- Example: Heart beat…not measure in half beats
What are Dichotomous variables
- When a variable can take on only two values….it is described as being dichotomous
- Example: Male/Female
What is a Nominal Variable
- Objects or people are assigned to categories according to some criterion
- Categories coded by name, number, etc although none of the categories has any quantitative value
- Categories are used purely as labels
- Example: Blood Type, Handedness, Side of Hemiplegic involvement
What is an Ordinal Variable
- Categories are rank ordered on the basis of an operationally defined characteristic
- Data organized into adjacent categories with a greater than less than relationship, one is greater or less than the other
- May have unequal intervals
- Example: None
What is an Interval Variable
- Rank order characteristic similar to Ordinal
- Unlike ordinal, demonstrates equal distances or intervals
- Example: Degrees in C or F
What is a Ratio Variable
- Interval Scale with a true zero
- Therefore, no negative values
- Measurement of zero represents complete absence of property being tested
- Example: ROM, Height, Weight
What are some issues with measuring constructs
- Constructs are not easily defined and as such are difficult to measure
- Example: Intelligence is not determined based on one measurement of reading ability or memory but is more complex
Discuss the importance of reliability in clinical measurement
- Extent to which a measurement is consistent and free from error
- Measurements have to be reliable to be valid. No validity without first reliability
- Reliability is fundamental to all aspects of measurement, without it we cannot have confidence in the data we collect or draw conclusions from those data
Explain the concept of measurement error
- The difference between the true value and the observed value
- Related to the “noise” that gets in the way of our finding the true score
Distinguish between random and systematic error
- Systematic Errors: Predictable errors of measurement, consistently overestimate or underestimate
- Random Errors: Due to chance and can affect a subjects score in an unpredictable way from trial to trial
Identify typical sources of measurement error
- Rater - Person taking measurement
- Instrument
- Variability of characteristic being measured
Describe the effect of regression toward the mean in repeated measurement
- Measurement errors are random and therefore normally distributed and will equal out over time
- Extreme scores on a pretest will move closer or regress toward the group average
Discuss how concepts of agreement and correlation relate to reliability
- Correlation reflects the degree of association between two sets of data but does not tell you anything about agreement
Define and give an example of intra-rater reliability
- Scores should match when the same examiner tests the same subjects on two or more occasions
Define and give an example of inter-rater reliability
- 2 or more examiners test the same subjects for the same characteristic using the same measure, scores should match
Define and give an example of test retest reliability
- Used to establish that an instrument is capable of measuring a variable with consistency
- A test is administered to the same group of subjects on more than one occasion; scores should match