AM: Standardization

Collected insufficient data

reason for testing error

Collected inaccurate data

reason for testing error

Used unsystematic data collection methods

reason for testing error

Obtained irrelevant data

reason for testing error

Failed to verify data collected

reason for testing error

Obtained data that has been contaminated by bias or prejudice

reason for testing error

Not accurately communicated data collected

reason for testing error

Define standardized test

a measurement tool that is published and has been designed for a specific purpose for use with a particular population

Components of a standardized test

detailed instructions explaining how to administer

when to administer

how to interpret scores

standardized tests should present results of investigations to evaluate the measure's ___

psychometric properties

Define non standardized test

assessments that provide the OT with information but have no precise comparison to a norm or criterion

What makes a test non-standardized?

no research behind it

Are there non-standardized tests that are structured?

yes... some are constructed to provide guidelines for the content and process of assessment

Non standardized tests with structured assessments are missing what?

psychometric properties have not been researched and documented

Raw score

- provides no meaning, just a number

- needs to be converted

(i.e. age to chronological age)

Frequency distribution

how test scores fall

Mean

measure of central tendency

- the average

What is the mean affected by?

outliers

Median

the middle score in a distribution; half the scores are above it and half are below it

Normal distribution

a bell-shaped curve, describing the spread of a characteristic throughout a population

T or F: standardized tests involve the collection of sufficient data for the purpose of the test

True

Standardized tests will have established __ and __

reliability and validity

Why method do standardized tests use

systematic data collection method

why does a standardized test have established reliability?

so data is collected accurately

Why does a standardized test have established validity

so that data obtained is related to the stated purpose and focus of the test

Standardized tests provide information about

confidence intervals

Why do standardized tests provide information about confidence intervals

so the OT can judge how likely it is that this result has provided a true picture of the person's ability and/or deficits

Standardized tests reduce what

the influence of bias or prejudice

Standardized tests have a record form for...

recording, analyzing and communicating scores

Ways assessment standardization can be done

1. Establishes uniform procedures, materials and scoring

2. Normative standardization

Describe uniform procedures, materials and scoring

materials, time limits, oral instructions, preliminary demonstrations, ways of handling questions from test taker

Define normative standardization

provides a numerical description of the test performance of a defined and well described sample group and serves as a reference from which OTs can evaluate the performance of the other people who take the test

Define well described sample group

normative group, normative sample, or reference group

Steps of standardization

1. Careful selection of test items

2. Administration to a representative sample drawn from a defined population (normative group)

3. Statistical analysis of results

4. Establish age based norms

5. Development of instructions and response scoring preocedures

Which standardization step establishes normal distribution of scores

3. Statistical analysis of results

T or F: most standardized tests are norm referenced

true

Norm referenced standardized assessments should provide detailed information on

the normative sample

Size of the sample for standardized assessments

not less than 100

Variables a norm referenced standardized assessments should include

- ethnocultural and SES levels of the individuals

- geographic distribution of selected participants for standardization

- other relevant variables (IQ or medical status, education and occupation of parents)

What is a con for norm referenced standardized assessments

clinical utility

- cost if the clinic does not already have the assessment

Pros for norm referenced standardized assessments

- accountability

- record keeping

- screening

- pre/post test

- to rank

- to discriminate between low and high achievers

What does norm referenced measure

broad skill areas

Each skill in norm referenced assessments are tested by how many items

less than four

Describe scores in norm referenced assessments

raw, standard, grade/age equivalent

What is reported with norm referenced assessments

achievement areas

Basal level

baseline

- tests require certain number of correct responses before deciding where to begin

Ceiling level

the point at which a specific number of incorrect responses has been made

How do basal and ceiling levels become raw scores, standard scores, percentile ranks, and age/grade equivalents?

?

Criterion referenced tests describe what

performance

Criterion referenced tests determine if what has been achieved

skills or concepts

Are criterion referenced tests standardized or non standardized

both

How are criterion referenced tests different from norm based tests

they are not normed based but can be compared to normed assessments

Criterion referenced tests: skills are expressed as

instructional objectives

Criterion referenced tests: individuals are compared with

a preset standard for acceptable achievement (others' performance is irrelevant)

Criterion referenced tests are closely related to

instruction

Criterion referenced tests measure knowledge on

small units

Skills are defined in three categories for criterion referenced tests

emerging, mastered, generalized

Normal distribution is influenced by

mean, median, and outliers

Define standard deviation

a measure of the spread or extent of variability of a set of scores around their mean

What is the most commonly used measure of spread

standard deviation

If the mean and standard deviation of a normal distribution are known, it is possible to compute what

the percentile rank associated with any given score

One standard deviation on either side of the mean represents what percentage of the population

34.13%

A score falling between minus one or plus one SD from the mean represents a score obtained by __ percent of the population

68.26%

The percent of population that falls between one and two standard deviations above the mean is

13.59%

- the curve is symmetrical so the number is the same for 1 and 2 SDs below the mean

Scores falling between minus two or plus two SD above the mean represent what percent of the population

95.44%