You will be presented with a citation segment from the section of a research paper. Classify the intent behind this citation by choosing from one of the following categories:

- Method: Cites the paper for its methodology or procedure.
- Background: Cites the paper to provide background information.
- Result: Cites the paper for its findings or results.

Your answer should be a single word from the following list of options: ["Method", "Background", "Result"]. Do not include any other text in your response.

Citation sentence:

Previous studies have provided very useful measures of relative intrinsic activity for MOPr agonists (Traynor and Nahorski, 1995; Yu et al., 1997; Kovoor et al., 1998; Zaki et al., 2000; Clark et al., 2006; Saidak et al., 2006), however this parameter is not able to differentiate full agonists in terms of efficacy and can be highly dependent upon receptor expression levels, so for these reasons, operational efficacy is a more useful measure.
Background