Assessment and Scoring - Part 2 Flashcards
What is the gaps in noise (GIN) test?
Developed by Musiek in 2005
Test of temporal processing
Measures temporal resolution
Monaural presentation (each ear tested individually)
7 years old to adults
Four test lists and one practice list (not linguistically loaded)
Four test lists contain between 29 and 36 trials
Each segment is a 6 s burst of white noise with 0 to 3 silent periods (a few trials contain no gaps)
2, 3, 4, 5, 6, 8, 10, 12, 15, or 20 ms gaps with 6 repetitions of each gap duration
Total number of gaps/test = 60
20 minutes to administer
Sensitivity for CANS lesions = 67%
Specificity for CANS lesions = 94%
How do you set-up for the GIN test?
Two-channels required
Left (test) channel (Ext A) = SIN stimuli (noise and gaps)
Right channel (Ext B) = gap indication signal (route to bone, “beep” presented to the right channel to alert examiner each time a gap occurs in the left channel)
Test administered at 35 to 50 dB SL re: SRT for each ear
Administer practice first
If > two false responses occur within first 5 segments, stop the test and reinstruct
What are the instructions for the GIN test?
In this test you are going to hear noise and within the noise there will be gaps of silence that will vary in length. Some may be very short and occasionally there will be no gaps. As soon as you hear the gap, press the response button. The noise levels may vary
What does early mean in the GIN test?
Gaps occurring early in the early third of the steady noise
What does middle mean in the GIN test?
Gaps occurring in the middle third of the steady noise
What does late mean in the GIN test?
Gaps occurring in the late third of the steady noise
What do the numbers in each trial mean in the GIN test?
Represents the length of the gap in msec
How do you score the GIN test?
O = correct; X = false positive; NR = No response
False positive = Listener responds when no gap is present
Allow two false positives (do not include in the scoring)
Additional false positives are tallied as errors when scoring
The authors of the test suggests that everyone develop their own normative data
What are the two ways in which the GIN test score is computed?
Total GIN score %:
Total correct number minus false positives ÷ (60 X 100) (one ear)
Total correct number minus false positives ÷ (120 X 100) (two ears)
> 52% is normal (8 to 11yrs)
> 54% is normal (12 to adults)
No norms for 7 years
Gap threshold:
Shortest gap duration that is perceived (at least 4 of the 6 gaps are correctly identified; performance for longer gap durations are not worse)
Approximate gap threshold (Ath)
Normal = < 4 to 6 ms
Concern = > 8 ms
A more sensitive measure than percent correct
What is the pitch pattern sequency test (PPST)?
Developed by Musiek and Pinheiro
7 years old to adults (use Bellis norms because they are age specific)
Linguistic loading
Assesses cerebral hemispheric disorders, corpus callosum dysfunction, and neuromaturation issues
Results can be hummed (for up to 12 year olds) to reduce linguistic loading in listeners with disruption in interhemispheric transfer of information
Sensitivity is moderate to high for verbal tasks (83%)
Monaurally presented
10 minutes to administer
Are abnormal results demonstrated in the PPST for children with learning and language disabilities?
Yes
But with normal intelligence because of neuromaturation
What is the PPST comprised of?
Three tone sequences of low and high frequency tones
The low frequency tone is 880 Hz and the high frequency tone is 1122 Hz (1430 Hz for younger children 6-9yrs to make it easier)
One tone is always different from the other two (6 possible patterns of tones)
120 patterns presented during the test; 60 for each ear
Generally acceptable to use half-lists (30 patterns per ear)
Listener can either whistle or hum the patterns or say the patterns out loud (high-low-high)
Humming is permitted till 12 years
Is there a practice test for the PPST?
No
What is the presentation for the PPST?
Presentation level: 50 dB SL re: 1000 Hz tonal threshold
Start with linguistic labeling
If a child cannot perform or cannot perform reliably, run another trial and ask the child to hum
Compare performance between responses
If humming improves scores it may indicate language learning problems or disruptions of interhemispheric transfer of auditory information
Will children with musical training do well on the PPST?
Yes
Children that are musically trained will ace this test even if they have auditory processing issues
What are PPST pattern reversals?
Certain pattern reversals are allows de to short-term memory storage problems
H-L-H reversed to L-H-L
H-H-L reversed to L-L-H
H-L-L reversed to L-H-H
L-H-L reversed to H-L-H
L-L-H reversed to H-H-L
L-H-H reversed to H-L-L
We will not count the reversals as correct, it needs to be exactly the same
Other places may count the reversals as correct
How do you score the PPST?
Final total score = % correct response + % correct reversals
Mean for % correct: 91% (9 to 10 yrs) and 90% (adults)
Mean for final total scores (with reversals): 96% (9 to 10 yrs) and 96% (adults)
Ranges: 88 to 100% (9 to 10 yrs) and 85 to 100% (adults)
* we will not use these norms in class because they have reversals
What norms should we use if we are not using reversals?
The Bellis norms
What is the duration pattern sequence test (DPT)?
Developed by Musiek, Baran, and Pinheiro
Test of duration discrimination, temporal ordering, and linguistic labeling
Sensitive to cortical lesions and disruption of interhemispheric transfer of auditory information
> 9 or 10 yrs to adults
Difficult to test for younger children
Duration pattern and pitch pattern should both be assessed (assessing two different temporal processes)
Don’t have clear information on what it means when someone fails this test
How is the DPT conducted?
Presentation at 50 dB SL re: 1000 Hz tone threshold
The level can be increased if a hearing loss is present
Monaural test
What are the test items for the DPT?
Three consecutive 1000 Hz tones one of which is either of a longer or shorter duration than the other two
Tonal duration either 500 or 250 ms
Six different combinations of long and short tones (LLS, LSL, SLL, SSL, SLS, LSS)
Each pattern is presented 10 times in random order
10 practice and 60 test items, 30 items per ear
Say: long-short-short (LSS)
What are the norms for the DPT?
Right ear -
Mean: 96%
SD: 4.36
Range: 87 to 100%
Left ear -
Mean: 96%
SD: 7.2
Range: 70 to 100%
*Lower level is a pass for the left ear because there is an inherently built in REA (at least until 12)
*Bellis has different age-specific norms
What are time compressed speech tests?
Low redundancy speech test
Utilizes time-compressed speech from various word lists to assess cortical auditory processing abilities
Elderly have significant difficulty with these tests (independent of peripheral HL)
By stressing the aging auditory system, these tests provide a good tool to assess speech processing deficits at the cortical level
Most of these tests are not standardized (affected by test stimuli and phonemic and acoustic distortions from the compression)
Any test designed to assess cortical function can be affected by dysfucntion of lower brain centers (as well as periphery)
What is NU-6 with 45% compression?
Monaural low redundancy test
Temporal characteristics of the signal are altered electronically without affecting frequency characteristics
Should be administered only when hearing is normal
Sensitive to diffuse pathology in the primary auditory cortex
7 yrs to adult
Administered with and without reverberation
Presented at a comfortable level (50 dB HL)
Listener repeats back the words
Calculate percent correct per ear
What is the time compressed sentence test?
Developed by Keith
Monaural low redundancy speech test
Performed monaurally for each ear separately
Time compression at 40% and 60%
Ten practice sentences are recorded with zero time compression
During presentation, do not pause the CD to allow more response time
You can pause between lists
How is the time compressed sentence test scored?
Each sentence is divided into three parts giving the possibility of three errors per sentence (max 3 errors)
Draw a line through errors
Errors in articles of speech such as “the” and “a” are not considered an error
% Correct = 100 – (# of errors x 3.3)
Add the total number of errors
Multiply that number by 3.3
Subtract total from 100 for percent correct
% Correct = 100 - (3 x 3.3) = 100 - 9.9 = 91.1%
Compare to norms
What is the low pass filtered NU-6 at 750 Hz test?
Monaural low redundancy speech test
Perform for each ear at 50 dB HL (Bellis, 2003)
Norms are reported for 1000 Hz cut-off male speaker lists and may not be equivalent for 750 Hz cut-off
*Problem with norms
What is the synthetic sentence identification-ipsilateral competing message test (SSI-ICM)?
Low redundancy monaural speech test (putting noise in environment - taking away extra redundant speech cues)
8 yrs to adult
Linguistic loading
Assesses auditory recognition, memory, and figure-ground
Assesses lower brainstem lesions
Sensitivity is moderate to high
Synthetic sentences presented to the target ear
Competing message (Davy Crockett story) presented to same ear at different message-to-competition ratios (MCRs)
How is the SSI-ICM scored?
The test is scored as a percentage score for each ear
Administered only if normal hearing at .5, 1, and 2 kHz
What is the synthetic sentence identification-contralateral competing message (SSI-CCM)?
Low-redundancy binaural speech test
Dichotic presentation assesses binaural separation
8 yrs to adult
Linguistically loaded
Moderate to high sensitivity
Assessing a central lesion
Sensitive to temporal lobe deficits
How is SSI-CCM scored?
Each ear is tested individually
The test is scored as a percentage for each ear
Administered only if normal hearing at .5, 1, and 2 kHz
For the SSI-ICM/CCM, are the initial sentences presented where 100% performance is expected?
Yes
At about 30 dB SL re: SRT; +10 MCR (signal is better)
What is the presentation for the testing of SSI-ICM/CCM?
We will present at 30 dB SL re: SRT
For the SSI-CCM the MCR is varied at 0 and -40 MCR (easier bc of spatial separation)
For SSI-ICM, the MCR is varied in 10 dB steps from 0, to +10, to -20 because it is a more difficult listening situation
Does the SSI depend on visual cues?
Yes
Which may be a limitation for adults with visual problems or for children with reading or developmental delays
Does the SSI show a maturation effect?
Yes
Test scores improve in successive age groups from 8 years to 25 years deteriorating sharply from 60 to 90 years
Can comparing PB-max and SSI-ICM?
Yes
Can provide a peripheral-central ratio that may be useful in judging prognosis of hearing aids or other rehabilitative measures
Which one is better determines what area has the deficit
When should SSI-ICM/CCM results be interpreted with caution?
In the presence of peripheral hearing loss
In the absence of age-appropriate norms for older adults and younger children
Children older or equal to 10 yrs perform like adults
What is SSI-ICM/CCM consisted of?
10 third-order approximation synthetic sentences that are seven words in length
Sentences follow the sentence structure while deviating from the standard rules of grammar and syntax
The advantage to this method is that use of monosyllabic words is avoided, a rapidly changing acoustic pattern is used, and dependence on context and linguistic abilities is reduced
The listener identifies by number 10 sentences from a list
*Last part of the sentence doesn’t make sense
What are the norms for the SSI-ICM?
+ 10 MCR = 100%
0 dB MCR = 100%
-10 dB MCR = 80%
-20 dB MCR = 55%
What are the norms for SSI-CCM?
0 dB MCR = 100%
-40 dB MCR = 100%
Adults with normal hearing and those with brainstem lesions should have 100% performance at all CCM-MCR conditions for both ears
Listeners with temporal lobe lesions tend to do poorly especially for the ear contralateral to the lesion
Is degree of asymmetry between ears important for SSI-ICM/CCM?
Yes
Asymmetry is a better indicator of central function than absolute (raw score) performance for each ear
Greater than 20% asymmetry between ears is considered abnormal
What is the VA dichotic digits test?
Author is Musiek in 1983
Ages: 7 years+
Low linguistic loading
High sensitivity
Administered only in the presence of symmetrical normal hearing
Presented simultaneously to both ears (different numbers)
Presentation level: 50 dB SL re: SRT
Useful for contour recognition, interhemispheric transfer, linguistic labeling and sequencing, and trace memory
Two digits between 1 to 10 (excluding 7) are presented to each ear simultaneously (4 digits total)
For example, the digits 5 & 9 presented to the right ear and 1 & 6 to the left ear
40 digits to each ear (total of 80)
5 practice stimuli
Listener needs to repeat the digits in any order
Scored by percent correct per ear (each digit is worth 2.5%) - age appropriate norms available
Testing binaural integration at the hemispheric level
What would the scores be for the VA dichotic digit test if there is right temporal lobe damage?
Scores reduced for the left ear
What would the scores be for the VA dichotic digit test if there is left temporal lobe damage?
Scores reduced for both ears
What would the scores be for the VA dichotic digit test if there is injury in other areas of the brain besides the temporal lobes?
Scores likely remain unaffected
Why is seven excluded from the VA dichotic test?
Seven is excluded because it has 2 syllables instead of 1
Why does the VA dichotic digit test have low linguistic loading?
Not looking at linguistic ability because they are just numbers, and they are expected to have mastered the ability to say these numbers (even for second language learners)
That is, unless they don’t know any English
What is the test setup for the VA dichotic digits test?
Binaural set-up
Channel 1, Ext A = L
Channel 2, Ext B - R
Use either track 3 or 4, not both
What is the random gap detection test (RGDT)?
Author is Keith (2000)
Age: 5 to 11:11 years
Assesses temporal resolution and temporal integrity at the cortical level
Gap detection threshold is the smallest interval where a listener consistently identifies two stimuli
Designed to assess temporal processing disorders that may be associated with phonological processing deficit, a problem with auditory discrimination, receptive language problems, and reading problems
No linguistic load (only pulses)
Appropriate for individuals with hearing loss and all linguistic backgrounds
Moderate to high sensitivity
What is the gap detection threshold for normal listeners?
1 to 2 ms
How is the random gap detection test performed?
Presented at 55 dB HL binaurally
Set up a two-channel audiometer to route the stimuli to right and left ears through Channel 1 and Channel 2
Practice trial with interstimulus interval (ISI) presented in increasing gaps from 0 to 40 ms
Only use external A because there is no competing noise (route to both ears)
How do you score the random gap detection test?
First calculate the lowest ISI for each frequency at which the listener identified hearing two rather than one tone at specific inter-pulse intervals
Then calculate the average gap detection threshold by averaging the threshold ISIs presented at each frequency
Don’t include the practice test score
Compare the average RGD threshold to normative values (by Keith too)
Abnormal results are 2 SD above the norm
Gap detection threshold > 20 msec is an indication of a temporal processing disorder for all ages (20+ score is a fail for all ages)
What is the staggered spondaic word test (SSW)?
Frequently administered binaural test
Not a strong evidence base
Simple to administer to a wide age group
Normative date (5-70 yrs)
Resistant to mild peripheral HL
Strong reliability and validity
Cost effective (about 10 mins to administer)
Each item is made up of two spondaic or compound words
Example: the word “up”, presented in a right noncompeting (RNC) condition (right ear first)
The words “stairs” and “down” that are presented simultaneously to the opposite ear are designated as right competing (RC) and left competing (LC) conditions, respectively
The last word “town” is the left noncompeting (LNC) condition
Also do left ear first conditions (LEF)
The 40 items alternate between REF and LEF
How do you set up the SSW test?
Via a two channel CD player or audiometer
The standard presentation is 50 dB SL re: SRT
It takes about 10 minutes to administer
Does the SSW categorize CAPD into 4 major subtypes (based on the Buffalo model)?
Yes
The Buffalo Model is a conceptualization of auditory processing disorders (APD) based on the results of a three-test battery
These tests include: SSW, phonemic synthesis test (focuses on discrimination of individual speech sounds and how they are synthesized into words), and the speech in noise test (words presented at +5 SNR for each ear then subtracted from the score in quiet; important for classifying tolerance-fading memory)
Can response bias for the SSW be scored?
Yes
Order effects (increased errors associated with presentation order; regardless of REF or LEF)
Ear effects (increased errors for REF vs. LEF)
Reversals (proper response provided in reversed order)
What are the different ways to score the SSW?
Number of Error Analysis (NOE), Original and Traditional analysis, and score form for all three analyses
What is the auditory stream segmentation test?
The perceptual parsing of acoustic sequences into ‘‘streams’’ composed of sounds arising from a given sound source or a group of sound sources
Sound source may differ in terms of location, intensity, and spectral or temporal complexity
Example: Sounds that have similar onsets, intensities, and harmonically related frequencies are more likely to be perceived as coming from the same source than sounds that begin at different times or differ in intensity and frequency
Sounds that originate from the same physical location are also likely to be perceived as a discrete stream
How does auditory stream segmentation work?
The ability to locate a sound in space involves the capacity of the CANS to detect, perceive, and compare small differences in the time of arrival and intensity of signals reaching the two ears
If a sound is located anywhere other than directly in front of the listener, the sound has to travel a different path length to reach the ears because one ear is nearer and one is farther from the sound source resulting in interaural time and intensity differences
What is binaural masking level difference test (BMLD or MLD)?
Binaural hearing enhances our ability to detect, identify, or discriminate signals in noisy environments
Age: 5 years +
No linguistic loading
Dichotic presentation assessing binaural interaction at the brainstem level (moderate sensitivity for low brainstem lesions)
Auditory segregation as seen in the “cocktail party” effect
Requires the listener to identify when stimulus pops out of the noise
MLD occurs because the more different the interaural relations of a signal the better the signal detectability
MLD experiments are conducted under headphones
Uses phase cues to detect differences
Deficits in the lower brainstem may affect lateralization and localization (affects ability to hear SIN)
What is the MLD terminology?
S = signal
M = masker (sometimes N, for noise)
So: binaural signal, no interaural phase difference
Mo: binaural masker, no interaural phase difference
Sm: monaural signal
Mm: monaural masker
Spi: binaural signal, 180° (radians) phase difference
Mpi: binaural masker, 180° (radians) phase difference
*Do all conditions and see which one is best
What is the general rule for MLD?
In general, if the perceived lateral position of masker and signal are different, the signal is likely to be more detectable than in the monotic condition
Best condition is when there is a binaural masker and a signal 180 degrees out of phase (between ears) presented binaurally
Is the best MLD higher for low frequencies (at or below 500 Hz)?
Yes
Phase is a low frequency signal, which is what we’re dealing with
Best MLD can be up to 10 or 15 dB
Only 2 to 3 MLD for high frequencies
How do you set up the astera for the MLD short test?
Performed at 500 Hz
SoMo condition first:
Masker presented at a constant level (50 dB) - set up in the right channel (channel 2)
Establish masked pure-tone threshold for 500 Hz
Example: Masked threshold is 45 dB HL
SpiMo next:
Masker stays at 50 dB
Establish pure tone threshold for 500 Hz
Example: threshold drops to 35 dB HL
*Greater than or equal to 10 dB HL is considered a release from masking (normal)
A normal MLD is not consistent with (C)APD, at least at the brainstem level
*Use channel 1 to establish threshold
*Keep button pressed when they hear the “wah wah” (warble) signal
How do you instruct the patient for the short MLD test on the astera?
Instruct patient to press the response button as long as the warble tone is heard through the noise and release when the tone goes away
Let the patient know that the tone will come and go but the noise will be constant
Reinstructing/modeling maybe needed for younger children as they may find instructions and the test difficult to understand/perform
How do you set up the MLD test?
Present the test binaurally routing through channels 1 and 2 for a two-channel audiometer for the right and left ears
The test is presented at 70 dB HL binaurally
The earphones must be in-phase
To test for phase: present a 500 Hz tone to each ear at equal intensities, the tone should be heard in the center of the head, if earphones are out-of-phase, tone will be heard in each ear
Listener is instructed to respond when tonal pulses are heard through the noise burst
Caution the patient that the tones are not always present
What is normal for the short version of MLD?
Score difference of at least 10 dB or better
*14 for the long version
Need to convert the number correct by the “threshold” and then do math
What is the listening in spatialized noise-sentences (LiSN-S) test?
Developed by NAL (Australia)
Authors are Cameron and Dillon (2006)
Norm data available for Australian, British, and US children
Measures the ability of children to segregate a targeted speech signal from simultaneously presented competing speech signals - auditory stream segmentation
SRT with competing noise using looped children’s stories
Age range: 6:2 to 30:3 (norms are not present for those over 30 years old)
What auditory cues aid with auditory stream segmentation?
Perceived spatial location of sounds and pitch of the speakers voices (help segregate the total stream)
*An inability to use this information has been found to be a leading cause of difficulty understanding speech in noisy environments, such as the classroom
How is the LiSN-S test performed?
The LiSN-S is presented using a personal computer
Output levels are directly controlled by the software via an external USB sound card
The test is performed binaurally under headphones
A three-dimensional auditory environment under headphones is created by pre-synthesizing the speech stimuli with head-related transfer functions (HRTFs) (can manipulate the HRTF to make you think the sound is coming from different places)
This approach is better than sound-field testing because
it minimizes the SPL variability and is more reliable in terms of placement of patient and speakers
How do you set up the LiSN-S test?
Using HRTFs, the targets are perceived as coming from directly in front of the listener (0 degrees azimuth)
Whereas the maskers, relative to the targets, vary according to their perceived spatial location
0 degrees vs. +90 degrees and -90 degrees azimuth
Speaker can be the same person or different to the stories
What are the 4 listening conditions for the LiSN-S test?
Same voice at 0 degrees (or low-cue SRT; hardest, relies on SNR)
Same voice at + 90 degrees
Different voices at 0 degrees
Different voices at + 90 degrees (or high-cue SRT; easiest, uses tonal and spatial cues)
Is the LiSN-S an adaptive test?
Yes, changes with responses
If you get them all right, the test will get harder
If you get them all wrong, the test will get easier
Until it has enough data to come to a conclusion (let the test stop itself)
Is the LiSN-S suitable for listeners with HL?
Yes
A prescribed gain amplifier has been incorporated into the LiSN-S software, which allows audiologists to assess how well hearing-impaired people will be able to understand speech in background noise, prior to hearing aid fitting
Although this population is not diagnosed with CAPD
Does the LiSN-S correlate with other dichotic tests, MLD, PPST, and RGDT?
No
It is different
In contrast to the simple MLD test, the more complex LiSN-S tests probably assess auditory streaming at higher levels, including the cortex and association areas for spatial stream segregation
Nonspatial and spatial performance measures of LiSN-S were also uncorrelated, providing further evidence that the LISN-S is sensitive in differentiating various forms of auditory streaming
Is the LiSN-S sensitive to auditory streaming deficits in children whose primary difficulties in the classroom stem from poor listening behavior?
Yes
As opposed to those with documented learning and attention disorders
Did the majority of children in the learning disorder group did not present with an auditory processing deficit on the LiSN-S or traditional CAPD testing?
Yes
Which may make the LISN-S useful in identification of a language vs. auditory disorder
These results suggest that the LiSN-S procedure is capable of differentiating not only an auditory vs. language disorder but also a spatial vs. vocal streaming segregation disorder
Is the LiSN-S a spatial processing disorder (SPD) pattern measure?
Yes
What does a child need if they have a spatial stream segregation deficit?
They require a higher signal-to-noise (SNR) in the classroom than normally hearing peers
HAT
If the teacher’s voice is made perceptually louder than the background noise, the target will more likely be perceived as a separate stream
This ease of listening may exert less demand on the cognitive resources required to attend to the target, thereby reducing fatigue and improving overall performance in in the classroom
Is there a link between a history of recurrent ear infections and spatial stream segregation deficit?
Studies are not large enough to conclude that
However, many of the children that were tested with the LiSN-S and did poorly did have recurrent OME in childhood
OME can cause spatial hearing deficits
A sufficiently large conductive loss results in an increased level of bone-conducted sound relative to air-conducted sound
This mismatch reduces the magnitude of interaural differences and the cues available to segment sources on the basis of their direction of arrival
The skills of spatial stream segregation may not be learned if the cues are either too weak or too inconsistent as a result of fluctuating hearing status during early childhood
Why might a ESL user have poorer test scores on the CAPD tests, but no auditory processing deficits?
Because of limited linguistic knowledge and experience with the English language
You should select tests with no/minimal linguistic loading
What tests can you use on children who use English as a second language?
RGDT test
GIN
MLD
PPST (if hummed, it removes the linguistic load)
DPT (duration pattern test)
Dichotic digits test (minimal linguistic load)
What are the 4 categories of CAPD tests that we need as least one test of each one?
Dichotic processes
Temporal processes
Binaural interaction
Monaural low redundancy speech/auditory closure processes
What are dichotic processes tests?
Dichotic digits
Competing sentences
SSI-CCM
SSW
What are the temporal processing tests?
GIN
Random gap detection
Duration on pattern test
Pitch pattern test
What are the binaural interaction tests?
Auditory fusion
Masking level difference
What are the monaural low redundancy speech/auditory closure processing tests?
NU6 filtered words
Time compressed sentences
SSI-ICM
Speech in noise
Can a diagnosis of CAPD be made conclusively after problems in other modalities have been ruled out?
Yes
Is the interpretation of test results most straightforward when deficits are unilateral?
Yes
Unilateral results indicate that the patient understood the task and that the outcome was not due to a linguistic, cognitive, or attention disorder (global issues)
A pronounced unilateral deficit, especially a left ear deficit, is one of the most common patterns observed on the (C)APD test battery
How do you identify educationally significant CAPD?
Test scores that are below the age-corrected normal region (> or equal to 2 standard deviation [SD]) for one or both ears on at least two different test measure
> or equal to 3 SD on one test measure
What is evidence of difficulty in an academic setting based on?
Observation
Multidisciplinary assessment
Academic performance
