How many inches (at least) should the stimulus be held from the suspects face when administering the HGN test?
12"
What is the minimum number of seconds that the stimulus should be held when checking for nystagmus at
maximum deviation?
4 seconds
What is the minimum pace (in seconds) that the stimulus should move when checking for onset of nystagmus
prior to 45 degree?
4 seconds
What is the recommended order that SFST's should be administered?
HGN, walk and turn, one leg stand
(True/False) If any one of the SFST elements is changed, the validity is compromised.
True
,Which type of nystagmus can be caused by red and blue strobe lights?
Optokinetic nystagmus
Which type of nystagmus is an indicator of a high BAC level for the impaired person OR an indication that they
are under the influence of drugs?
Vertical Gaze Nystagmus
This is the total number of clue in the HGN that are needed to indicate a test failure:
4
Based upon the original research how accurate is HGN?
77%
(true/false) If a suspect is wearing high heels (2" or higher) an officer should provide them with the option of
taking them off when performing the walk and turn test?
true
, This is the number of inches that must be between heal and toe in order to be considered a clue during the walk
and turn test?
1/2"
This is the minimum number of inches that the hands/arms must deviate from the sides of body during the walk
and turn in order to be considered a "clue" of impairment:
6"
Six valid clues of the HGN test:
1. lack of smooth pursuit
2. distinct and sustained nystagmus at maximum devation
3. onset of nystagmus prior to 45 degrees
Both eyes, makes six
12"
What is the minimum number of seconds that the stimulus should be held when checking for nystagmus at
maximum deviation?
4 seconds
What is the minimum pace (in seconds) that the stimulus should move when checking for onset of nystagmus
prior to 45 degree?
4 seconds
What is the recommended order that SFST's should be administered?
HGN, walk and turn, one leg stand
(True/False) If any one of the SFST elements is changed, the validity is compromised.
True
,Which type of nystagmus can be caused by red and blue strobe lights?
Optokinetic nystagmus
Which type of nystagmus is an indicator of a high BAC level for the impaired person OR an indication that they
are under the influence of drugs?
Vertical Gaze Nystagmus
This is the total number of clue in the HGN that are needed to indicate a test failure:
4
Based upon the original research how accurate is HGN?
77%
(true/false) If a suspect is wearing high heels (2" or higher) an officer should provide them with the option of
taking them off when performing the walk and turn test?
true
, This is the number of inches that must be between heal and toe in order to be considered a clue during the walk
and turn test?
1/2"
This is the minimum number of inches that the hands/arms must deviate from the sides of body during the walk
and turn in order to be considered a "clue" of impairment:
6"
Six valid clues of the HGN test:
1. lack of smooth pursuit
2. distinct and sustained nystagmus at maximum devation
3. onset of nystagmus prior to 45 degrees
Both eyes, makes six
