26204
After an initial overview of NRT and its FDA - approved indications for use , we review randomized trials in which clinical delivery of NRT was manipulated and tested , in an attempt to enhance efficacy , through ( 1 ) duration of use ( pre - quit and extended use ) , ( 2 ) amount of use ( high - dose and combination NRT ) , ( 3 ) tailoring to specific smoker groups ( genotype and phenotype ) , or ( 4 ) use of NRT for novel purposes ( relapse prevention , temporary abstinence , cessation induction ) .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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