Westat

About: Westat is a company organization based out in Rockville, Maryland, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 1058 authors who have published 2076 publications receiving 117529 citations. The organization is also known as: Westat Corporation & Westat Inc.

Comorbidity measures for use with administrative data.

Abstract: Objectives.This study attempts to develop a comprehensive set of comorbidity measures for use with large administrative inpatient datasets.Methods.The study involved clinical and empirical review of comorbidity measures, development of a framework that attempts to segregate comorbidities from other

The Risk of Transfusion-Transmitted Viral Infections

Abstract: Background Accurate estimates of the risk of transfusion-transmitted infectious disease are essential for monitoring the safety of the blood supply and evaluating the potential effect of new screening tests. We estimated the risk of transmitting the human immunodeficiency virus (HIV), the human T-cell lymphotropic virus (HTLV), the hepatitis C virus (HCV), and the hepatitis B virus (HBV) from screened blood units donated during the window period following a recent, undetected infection. Methods Using data on 586,507 persons who each donated blood more than once between 1991 and 1993 at five blood centers (for a total of 2,318,356 allogeneic blood donations), we calculated the incidence rates of seroconversion among those whose donations passed all the screening tests used. We adjusted these rates for the estimated duration of the infectious window period for each virus. We then estimated the further reductions in risk that would result from the use of new and more sensitive viral-antigen or nucleic acid s...

Sampling Methods for Random Digit Dialing

Abstract: A method of sample selection for household telephone interviewing via random digit dialing is developed which significantly reduces the cost of such surveys as compared to dialing numbers completely at random. The sampling is carried out through a two-stage design and has the unusual feature that although all units have the same probability of selection, it is not necessary to know the probabilities of selection of the first-stage or the second-stage units. Simple random sampling of possible telephone numbers, within existing telephone exchanges, is inefficient because only about 20 percent of these numbers are actually telephone numbers assigned to households. The method of selection proposed reduces the proportion of unused numbers sharply.

Cost of lost productive work time among US workers with depression.

Abstract: ContextEvidence consistently indicates that depression has adversely affected work productivity. Estimates of the cost impact in lost labor time in the US workforce, however, are scarce and dated.ObjectiveTo estimate the impact of depression on labor costs (ie, work absence and reduced performance while at work) in the US workforce.Design, Setting, and ParticipantsAll employed individuals who participated in the American Productivity Audit (conducted August 1, 2001–July 31, 2002) between May 20 and July 11, 2002, were eligible for the Depressive Disorders Study. Those who responded affirmatively to 2 depression-screening questions (n = 692), as well as a 1:4 stratified random sample of those responding in the negative (n = 435), were recruited for and completed a supplemental interview using the Primary Care Evaluation of Mental Disorders Mood Module for depression, the Somatic Symptom Inventory, and a medical and treatment history for depression. Excess lost productive time (LPT) costs from depression were derived as the difference in LPT among individuals with depression minus the expected LPT in the absence of depression projected to the US workforce.Main Outcome MeasureEstimated LPT and associated labor costs (work absence and reduced performance while at work) due to depression.ResultsWorkers with depression reported significantly more total health-related LPT than those without depression (mean, 5.6 h/wk vs an expected 1.5 h/wk, respectively). Eighty-one percent of the LPT costs are explained by reduced performance while at work. Major depression accounts for 48% of the LPT among those with depression, again with a majority of the cost explained by reduced performance while at work. Self-reported use of antidepressants in the previous 12 months among those with depression was low (<30%) and the mean reported treatment effectiveness was only moderate. Extrapolation of these survey results and self-reported annual incomes to the population of US workers suggests that US workers with depression employed in the previous week cost employers an estimated $44 billion per year in LPT, an excess of $31 billion per year compared with peers without depression. This estimate does not include labor costs associated with short- and long-term disability.ConclusionsA majority of the LPT costs that employers face from employee depression is invisible and explained by reduced performance while at work. Use of treatments for depression appears to be relatively low. The combined LPT burden among those with depression and the low level of treatment suggests that there may be cost-effective opportunities for improving depression-related outcomes in the US workforce.

Epidemiologic Evidence Showing That Human Papillomavirus Infection Causes Most Cervical Intraepithelial Neoplasia

Abstract: Given improvements in human papillomavirus (HPV) testing that have revealed a strong link between sexual activity history and cervical HPV infection the authors conducted a large case-control study of HPV and cervical intraepithelial neoplasia (CIN) to evaluate whether sexual behavior and the other established risk factors for CIN influence risk primarily via HPV infection. The authors studied 500 women with CIN and 500 control subjects receiving cytologic screening at Kaiser Permanente a large prepaid health plan in Portland Oregon. The established epidemiologic risk factors for CIN were assessed by telephone interview. The authors performed HPV testing of cervicovaginal lavage specimens by gene amplification using polymerase chain reaction with a consensus primer to target the L1 gene region of HPV. Unconditional logistic regression analysis was used to estimate relative risk of CIN and to adjust the epidemiologic associations for HPV test results to demonstrate whether the associations were mediated by HPV. The case subjects demonstrated the typical epidemiologic profile of CIN: they had more sex partners more cigarette smoking earlier ages at first sexual intercourse and lower socioeconomic status. Statistical adjustment for HPV infection substantially reduced the size of each of these case-control differences. 76% of cases could be attributed to HPV infection; the results of cytologic review suggested that the true percentage was even higher. Once HPV infection was taken into account an association of parity with risk of CIN was observed in both HPV-negative and HPV-positive women. The data show that the great majority of all grades of CIN can be attributed to HPV infection particularly with the cancer-associated types of HPV. In light of this conclusion the investigation of the natural history of HPV has preventive as well as etiologic importance. (authors)