assessment concepts reliability validity inter-rater test-retest construct content...

assessment concepts

reliability

validity

• inter-rater • test-retest

• construct• content• concurrent/descriptive• predictive/criterion

standardizationuse of consistent set of standards in procedure for testing, scoring, evaluation

clinical interview

mental status exam

1. appearance & behavior

1. thought process

1. mood & affect

1. intellectual functioning

1. sensorium

semi-structured clinical interview

DSM Multiaxial System

Axis I: Major DisordersAxis II: Personality Disorders & Mental RetardationAxis III: Medical ConditionsAxis IV: Psychosocial & Environmental FactorsAxis V: Global Assessment of Functioning (GAF)

testing

Projective tests

• Rorschach• Thematic Apperception Test

testingPersonality Inventories (e.g .MMPI)

Also:Lie Scale Malingering Scale

testing

Neuropsychological Tests

-tasks are associated with functioning of specific brain areas-poor task performance indicates impaired function (and possibly physical damage) of the specific brain area

structural vs. functional

CTMRI

PETfMRI

testing

Neuroimaging

CT scan

• x-ray & sensor• low spatial resolution

computerized axial tomography

MRI

high spatial resolution

magnetic resonance imaging

PET scanpositron emission tomography

• low resolution (both temporal & spatial)

• radioactive material is absorbed

fMRI scan

• higher spatial resolution than PET (poor temporal resolution)

• 3-D images possible

• hemoglobin (blood protein that binds oxygen) changes its magnetic field response

functional MRI

EEG

psychophysiological techniques

EOG

EMG

“electrophysiology”

= electro-myograph

= electro-oculograph

= electro-encephalograph

EEGelectroencephalography

record of electrical activity below each electrode

EEG brainwaves characterize mental states

EMGelectromyograph

SCRskin conductance/resistance

index of physiological arousal

classification

Classification – categoriesTaxonomy – scientific categoriesNosology – psych or medical categories

Classical Categorical ApproachUsed in medicine; discrete categories

Dimensional ApproachCharacteristics range from low to high. Not “presence

or absence” but rather “How much?”

Prototypical ApproachEssential features + meet # symptoms for dx

types of research

• descriptive

• experimental

-observation (naturalistic vs lab)

-survey

-case study

-correlational studies

-epidemiology

correlation

Are two variables related?

1. Do they move together or opposite?

2. How strongly?

(if they are strongly related, we can predict one from the other)

correlation coefficient

POSITIVENEGATIVE NO ASSN

-1.00 0 +1.00

+ / -

number

= direction

= strength

weak (0 - .40)moderate (.41 - .69)strong (.70 – 1.00)

correlational studies

POSITIVE NEGATIVE NO ASSN

To a group of people, give a questionnaire about their degree of shyness.

Are shy people happy?

To this same group, give a questionnaire about their degree of happiness.

Each person has two scores. Use correlation.

Is there a relationship between shyness & happiness? (Did one cause the other?)

correlational studies

Correlation is NOT causation!

A

A

B

B

C

B

A

example

e.g. Ice cream sales positively correlate with the occurrence of violent crime.

ice cream sales

Variable 1 Variable 2

violent crime

independentvariable

dependentvariable

experimental research

confoundingvariable

experimental research

Interested in a specific treatment?

Compare its effects to a control condition.

“baseline” comparison

internal validity

external validity - generalizability

experimental research

statistical vs clinical significance

repeated measurements

withdrawal designs

single case designs

multiple baseline

family studies

adoption studies

twin studies

genetics

genotype

phenotype

molecular genetic studies

linkage analysis

association study

- searches for approximate location of a gene

- tests a candidate disease gene

behavior over time

prevention studies

cross sectional

-health promotion-universal -selected-indicated

- diff age cohorts compared at same time

longitudinal- one group tracked over time

sequential- cross sectional study done longitudinally