1071
We addressed this question by comparing three groups of subjects , MS patients with fatigue , MS patients without fatigue and healthy controls , matched for age and sex , on measures of alertness ( self - ratings on the Epworth and Stanford Sleepiness Scales and on a battery of visual analogue scales ; critical flicker fusion frequency ; Pupillographic Sleepiness Test ; choice reaction time ) and autonomic function ( systolic and diastolic blood pressure , heart rate , pupil diameter ) , and by examining the effect of a single dose ( 200 mg ) of modafinil on these measures .
 modafinil
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 modafinil