RAND Corporation

About: RAND Corporation is a nonprofit organization based out in Santa Monica, California, United States. It is known for research contribution in the topics: Population & Health care. The organization has 9602 authors who have published 18570 publications receiving 744658 citations.

Distinguishing optimism from pessimism : relations to fundamental dimensions of mood and personality

Abstract: Contrary to unidimensional conceptions of optimism and pessimism, factor analysis of 2 widely used instruments revealed that optimism and pessimism are empirically differentiable, but related, constructs. Moreover, consistent with expectations, optimism and pessimism were differentially linked with fundamental dimensions of mood and personality. Pessimism was principally associated with neuroticism and negative affect. Optimism was primarily associated with extraversion and positive affect. Findings are discussed with reference to current conceptual and measurement models of optimism and pessimism and their relations to broad dimensions of mood and personality

Evaluating Value-Added Models for Teacher Accountability

Abstract: Does value-added modeling (VAM) demonstrate the importance of teachers to student outcomes? The authors clarify the primary questions raised by VAM for measuring teacher effects, review the most important recent applications of VAM, and discuss a variety of statistical and measurement issues that might affect the validity of VAM inferences. The authors identify numerous possible sources of error and bias in teacher effects and recommend a number of steps for future research into these potential errors.

Pharmacy Benefits and the Use of Drugs by the Chronically Ill

Abstract: ContextMany health plans have instituted more cost sharing to discourage use of more expensive pharmaceuticals and to reduce drug spending.ObjectiveTo determine how changes in cost sharing affect use of the most commonly used drug classes among the privately insured and the chronically ill.Design, Setting, and ParticipantsRetrospective US study conducted from 1997 to 2000, examining linked pharmacy claims data with health plan benefit designs from 30 employers and 52 health plans. Participants were 528 969 privately insured beneficiaries aged 18 to 64 years and enrolled from 1 to 4 years (960 791 person-years).Main Outcome MeasureRelative change in drug days supplied (per member, per year) when co-payments doubled in a prototypical drug benefit plan.ResultsDoubling co-payments was associated with reductions in use of 8 therapeutic classes. The largest decreases occurred for nonsteroidal anti-inflammatory drugs (NSAIDs) (45%) and antihistamines (44%). Reductions in overall days supplied of antihyperlipidemics (34%), antiulcerants (33%), antiasthmatics (32%), antihypertensives (26%), antidepressants (26%), and antidiabetics (25%) were also observed. Among patients diagnosed as having a chronic illness and receiving ongoing care, use was less responsive to co-payment changes. Use of antidepressants by depressed patients declined by 8%; use of antihypertensives by hypertensive patients decreased by 10%. Larger reductions were observed for arthritis patients taking NSAIDs (27%) and allergy patients taking antihistamines (31%). Patients with diabetes reduced their use of antidiabetes drugs by 23%.ConclusionsThe use of medications such as antihistamines and NSAIDs, which are taken intermittently to treat symptoms, was sensitive to co-payment changes. Other medications—antihypertensive, antiasthmatic, antidepressant, antihyperlipidemic, antiulcerant, and antidiabetic agents—also demonstrated significant price responsiveness. The reduction in use of medications for individuals in ongoing care was more modest. Still, significant increases in co-payments raise concern about adverse health consequences because of the large price effects, especially among diabetic patients.

A theorem on flows in networks

Abstract: The theorem to be proved in this note is a generalization of a well-known combinatorial theorem of P. Hall, [4].