			Home About us Contact

Exposure Measures (exposure + measure)

Distribution by Scientific Domains

Medical Sciences	87%

Selected Abstracts

Psychometric properties of the Trauma Assessment for Adults

DEPRESSION AND ANXIETY, Issue 2 2009
Matt J. Gray Ph.D.
Abstract Background: The Trauma Assessment for Adults (TAA) was developed to facilitate the assessment of exposure to traumatic events that could result in posttraumatic stress disorder (PTSD). The TAA inquires about numerous potentially traumatic events that an individual may have experienced. Although the TAA has been used extensively for clinical and research purposes, its psychometric properties have never been formally evaluated. The objective of the present investigation was to evaluate the psychometric properties of this frequently used measure. Methods: The studies reported here describe the performance of the TAA in two samples,college undergraduates (N=142) and community mental health center clients (N=67). Among undergraduates, 1-week temporal stability was evaluated and, in both samples, item- and scale-level convergence of the TAA with an established trauma exposure measure was assessed. Convergence of the TAA with clinically related constructs was also evaluated. Results: The TAA exhibited adequate temporal stability (r=.80) and satisfactory item-level convergence with existing measures of trauma history among college students. In the clinical sample, the TAA again converged well with an established measure of trauma exposure (r=.65). It was not as strongly predictive, in either sample, of trauma-related distress relative to an alternate trauma exposure measure. Conclusion: Although it performs satisfactorily, the TAA does not appear to be superior to other existing measures of trauma exposure. Depression and Anxiety, 2009. © 2008 Wiley-Liss, Inc. [source]

Evaluating measurement error in estimates of worker exposure assessed in parallel by personal and biological monitoring

AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 2 2007
Elaine Symanski PhD
Abstract Background While studies indicate that the attenuating effects of imperfectly measured exposure can be substantial, they have not had the requisite data to compare methods of assessing exposure for the same individuals monitored over common time periods. Methods We examined measurement error in multiple exposure measures collected in parallel on 32 groups of workers. Random-effects models were applied under both compound symmetric and exponential correlation structures. Estimates of the within- and between-worker variances were used to contrast the attenuation bias in an exposure-response relationship that would be expected using an individual-based exposure assessment for different exposure measures on the basis of the intra-class correlation coefficient (ICC). Results ICC estimates ranged widely, indicative of a great deal of measurement error in some exposure measures while others contained very little. There was generally less attenuation in the biomarker data as compared to measurements obtained by personal sampling and, among biomarkers, for those with longer half-lives. The interval ICC estimates were oftentimes wide, suggesting a fair amount of imprecision in the point estimates. Ignoring serial correlation tended to over estimate the ICC values. Conclusions Although personal sampling results were typically characterized by more intra-individual variability than inter-individual variability when compared to biological measurements, both types of data provided examples of exposure measures fraught with error. Our results also indicated substantial imprecision in the estimates of exposure measurement error, suggesting that greater emphasis needs to be given to studies that collect sufficient data to better characterize the attenuating effects of an error-prone exposure measure. Am. J. Ind. Med. 50:112,121, 2007. © 2006 Wiley-Liss, Inc. [source]

Issues in the epidemiological investigation of dry mouth

GERODONTOLOGY, Issue 2 2005
W. Murray Thomson
Despite decades of research, much remains unanswered about the epidemiology of dry mouth. This review aims to provide an overview of the condition's epidemiology and the issues to consider when planning an epidemiological study of dry mouth. The latter can be broadly grouped into: study design; sampling and statistical power considerations; the measurement of dry mouth; and the selection, nature and measurement of relevant exposure measures, including medications and potential confounding variables. Each of these is discussed, in order to provide guidance for prospective researchers based on experience with past research. Finally, an agenda for further epidemiological research into dry mouth is proposed. [source]

Carbaryl exposure and incident cancer in the Agricultural Health Study

INTERNATIONAL JOURNAL OF CANCER, Issue 8 2007
Rajeev Mahajan
Abstract Carbaryl is a carbamate insecticide with a broad spectrum of uses in agricultural, commercial and household settings. It has previously been linked with non-Hodgkin lymphoma (NHL) but studies of cancer risk in humans are limited. We examined occupational carbaryl use and risk of all cancers in the Agricultural Health Study, a prospective study of a cohort of pesticide applicators in North Carolina and Iowa. This analysis included 21,416 subjects (1,291 cases) enrolled from 1993,1997 and followed for cancer incidence through 2003. Pesticide exposure and other data were collected using self-administered questionnaires. Poisson regression was used to calculate rate ratios (RRs) and 95% confidence intervals (CIs) while controlling for potential confounders. Carbaryl was not associated with cancer risk overall. Relative to subjects who never used carbaryl, melanoma risk was elevated with >175 lifetime exposure-days (RR = 4.11; 95%CI, 1.33,12.75; p -trend = 0.07), >10 years of use (RR = 3.19; 95%CI, 1.28,7.92; p -trend = 0.04), or ,10 days of use per year (RR = 5.50; 95%CI, 2.19,13.84; p -trend < 0.001). Risk remained after adjusting for sunlight exposure. Although not significant, there appeared to be a trend of decreasing prostate cancer risk with increasing level of exposure. A small increase in NHL risk was observed using some, but not all, exposure measures. No associations were observed with other examined cancer sites. Because the observed results were not hypothesized a priori and because of limited study of their biological plausibility, they should be interpreted with caution. © 2007 Wiley-Liss, Inc. [source]

War-related posttraumatic stress disorder in Black, Hispanic, and majority White Vietnam veterans: The roles of exposure and vulnerability

JOURNAL OF TRAUMATIC STRESS, Issue 2 2008
Bruce P. Dohrenwend
Elevated prevalence rates of chronic posttraumatic stress disorder (PTSD) have been reported for Black and Hispanic Vietnam veterans. There has been no comprehensive explanation of these group differences. Moreover, previous research has relied on retrospective reports of war-zone stress and on PTSD assessments that fail to distinguish between prevalence and incidence. These limitations are addressed by use of record-based exposure measures and clinical diagnoses of a subsample of veterans from the National Vietnam Veterans Readjustment Study (NVVRS). Compared with Majority White, the Black elevation is explained by Blacks' greater exposure; the Hispanic elevation, by Hispanics' greater exposure, younger age, lesser education, and lower Armed Forces Qualification Test scores. The PTSD elevation in Hispanics versus Blacks is accounted for mainly by Hispanics' younger age. [source]

Evaluating measurement error in estimates of worker exposure assessed in parallel by personal and biological monitoring

The exposure-time-response relationship between occupational asbestos exposure and lung cancer in two German case-control studies,

AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 2 2002
Michael Hauptmann PhD
Abstract Background Numerous studies have been carried out to evaluate the association between lung cancer and occupational asbestos exposure. However, the effects of timing of exposure have not been analyzed thoroughly. Methods Two German case-control studies with data on occupational asbestos exposure histories have been pooled. Duration of work in potentially asbestos exposed jobs and two derived weighted exposure measures are analyzed together with time since last exposure. A spline function is used to model the effect of time since exposure. Results The odds ratios (OR) and corresponding 95% confidence intervals were 1.8 (1.2, 2.7) and 2.4 (1.7, 3.4) for subjects having worked for 3 to 7 years and 8 or more years, respectively, in a job with potential asbestos exposure compared to never-exposed. Based on an evaluation of time since last exposure, the OR decreased significantly to about one-half after more than 20 years since exposure ceased. Using a spline function, applied to workers' complete exposure histories, the effect of an increment of exposure is greatest 10,15 years after that exposure was received. Conclusions In contrast to previous indications, the risk of lung cancer increases soon after asbestos exposure, with its maximum effect from 10 to 15 years after the exposure was received. Am. J. Ind. Med. 41:89,97, 2002. Published 2002 Wiley-Liss, Inc. [source]