SLP1046 SCORING AND INTERPRETATION OF NST

Mean

• Measures CENTRAL TENDENCY

• Computed by adding the data set and divided by the # of data

• AKA average: adding all the scores divided by the number of items

Standard Deviation

• Quantifies the amount of variation

Low Standard Deviation

data are close with one another, little variability

High Standard Deviation

Data are spread out

Bell Curve

shows the natural distribution of scores

Compare results easier

Why do we need to standardize the scores?

Norms

• The performance sample of children drawn from the population

Severity

How far away the child is from the mean

Left-skew Bell Curve

• Most are low scores

• Tail is longer on the left side

Right-skew Bell Curve

• Most are high scores

• Tail is longer on the right side

Standard Score

•  represent equal units across the range of scores

• Examples: z scores, t-scores, scaled scores

Percentile Rank

• Tells the relative position from the rest of the population

• Tells what proportion of the norming population scored lower than the subject taking the test

• Having 100 test takers and the average is 50, you do better than 50 of the test takers but 50 did better than you.

Age-Equivalent Scores

• Based on the raw scores, it gives us the equivalent age and grade. 

• Caution should be made when using this, although it is often used.

  • If a 42 year old and a 15 year old both had the score of 15 out of 30, the 42 year old did worse because it shows a greater delay.

Confidence Interval

• Gives you the range of scores that you can be at a certain percentage (68%, 90%, 95%) sure contains the child’s “true” score.

• Maybe on a bad day, the child performs less than their usual self → the test will give a range.

• You are between a percentage, and your true score lies within a range.

Eligibility

• identify the need for services because it is costly. 

Computation of Standardized Score

Raw Score - Mean/Standard Deviation

+

symbol for above the mean

-

symbol for below the mean

Very Low Range/Severe

Severity Classification of 70 and below (CELF4)

Low Range/Moderate

Severity Classification of 71-77 (CELF4)

Marginal/Below Average/Mild

Severity Classification of 78-85 (CELF4)

Average

Severity Classification of 86-114 (CELF4)

Above Average

Severity Classification of 115 and above (CELF4)

Nature of the disorder

• The differences in the performance will determine the __________ and will help identify the FOCUS of the therapy.

Importance of Discrepancy

• The criteria is determined by the developer

• Ex: If the criteria is 5 and the child is 7 = significant

Administration for Tests

• Know where to start

• How to progress

• How to respond the child

• document