11608
BACKGROUND : Previous studies have indicated that the 60 - , 30 - , 28 - and 12 - item versions of the General Health Questionnaire ( GHQ ) are liable to retest effects , especially when administered multiple times with short intervals .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
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