May I know what factors can affect the inter-rater reliability of a scale used to measure relapse behaviour of a drug user, and how these can be minimized?

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I see. Thank a lot!

Factors that can affect the inter-rater reliability of a scale used to measure relapse behaviour of a drug user include differences in rater training and experience, rater bias, and differences in rating criteria. These can be minimized by providing standardized training to the raters, using clear rating criteria, and monitoring the agreement between raters.