Reliability formulas that do not assume experimental independence

Tautologies are established for the reliability coefficient ² _t of the sum ofn part scores. It is not assumed that the part scores are experimentally independent of each other nor that the parts are equivalent to each other. The tautologies show the exact role played by experimental dependence and nonequivalence of parts, respectively, in the reliability of the sum. The formal algebra is appropriate to reliability in the sense of repeated trials of the same test, as well as in the sense of a universe of parallel tests, although the empirical meanings are different. Emphasis is on practical formulas that require information from only a single experiment (or test). These can take the form only of lower bounds to ² _t , four of which are developed.     

A randomized trial of a brief primary-care-based intervention for reducing at-risk drinking practices.

This randomized trial evaluated an intervention for reducing at-risk drinking practices in a sample of 307 patients. Eligible drinking patterns included chronic drinking (> or = 2 drinks per day in the past month), binge drinking (> or = 5 drinks per occasion at least twice in the past month), and drinking and driving (driving after > 2 drinks in the past month). Members of the intervention group received a message from their physician during their regularly scheduled visit, a self-help manual, written personalized feedback, and up to 3 telephone counseling calls. Dropout was significantly higher in the intervention than control group.