3002
Episodic memory , indexed by scores on the Hopkins Verbal Learning Task - revised ( HVLT - R ) , was poorer , relative to baseline , in the placebo pre - treated group ( - 10 . 6 +/- 18 . 9 % ) compared with the CBD group ( - 0 . 4 % +/- 9 . 7 % ) ( t = 2 . 39 , p < 0 . 05 ) .
 CBD
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 CBD