Multisite trials, in which individuals are randomly assigned to alternative treatment arms within sites, offer an excellent opportunity to estimate the cross-site average effect of treatment assignment (intent to treat or ITT) "and" the amount by which this impact varies across sites. Although both of these statistics are substantively…

Combining diverse methods in a single study raises a problem: What should be done when the findings of one method of investigation conflict with those of another? We illustrate this problem using an example in which three study phases--quantitative, qualitative, and intervention--were applied. The findings coming from the quantitative phase did…

Combining diverse methods in a single study raises a problem: What should be done when the findings of one method of investigation conflict with those of another? The authors illustrate this problem using an example in which three study phases--quantitative, qualitative, and intervention--are applied. The findings from the quantitative phase did…