Shaohung Wang

Bio: Shaohung Wang is an academic researcher from Thomson Reuters. The author has contributed to research in topics: Indirect costs & Absenteeism. The author has an hindex of 21, co-authored 29 publications receiving 3517 citations. Previous affiliations of Shaohung Wang include Massachusetts Institute of Technology.

Health, absence, disability, and presenteeism cost estimates of certain physical and mental health conditions affecting U.S. employers.

Abstract: Evidence about the total cost of health, absence, short-term disability, and productivity losses was synthesized for 10 health conditions. Cost estimates from a large medical/absence database were combined with findings from several published productivity surveys. Ranges of condition prevalence and associated absenteeism and presenteeism (on-the-job-productivity) losses were used to estimate condition-related costs. Based on average impairment and prevalence estimates, the overall economic burden of illness was highest for hypertension ($392 per eligible employee per year), heart disease ($368), depression and other mental illnesses ($348), and arthritis ($327). Presenteeism costs were higher than medical costs in most cases, and represented 18% to 60% of all costs for the 10 conditions. Caution is advised when interpreting any particular source of data, and the need for standardization in future research is noted.

The health and productivity cost burden of the "top 10" physical and mental health conditions affecting six large U.S. employers in 1999.

Abstract: A multi-employer database that links medical, prescription drug, absence, and short term disability data at the patient level was analyzed to uncover the most costly physical and mental health conditions affecting American businesses. A unique methodology was developed involving the creation of patient episodes of care that incorporated employee productivity measures of absence and disability. Data for 374,799 employees from six large employers were analyzed. Absence and disability losses constituted 29% of the total health and productivity related expenditures for physical health conditions, and 47% for all of the mental health conditions examined. The top-10 most costly physical health conditions were: angina pectoris; essential hypertension; diabetes mellitus; mechanical low back pain; acute myocardial infarction; chronic obstructive pulmonary disease; back disorders not specified as low back; trauma to spine and spinal cord; sinusitis; and diseases of the ear, nose and throat or mastoid process. The most costly mental health disorders were: bipolar disorder, chronic maintenance; depression; depressive episode in bipolar disease; neurotic, personality and non-psychotic disorders; alcoholism;, anxiety disorders; schizophrenia, acute phase; bipolar disorders, severe mania; nonspecific neurotic, personality and non-psychotic disorders; and psychoses. Implications for employers and health plans in examining the health and productivity consequences of common health conditions are discussed.

The direct and indirect costs of untreated insomnia in adults in the United States.

Abstract: Objectives To estimate the direct and indirect cost burden of untreated insomnia among younger adults (age 18-64), and to estimate the direct costs of untreated insomnia for elderly patients (age 65 and over). Design A retrospective, observational study comparing insomnia patients to matched samples without insomnia. Settings Self-insured, employer sponsored health insurance plans in the U.S. Patients or participants 138,820 younger adults and 75,558 elderly patients with insomnia, plus equal-sized, matched comparison groups. Interventions NA. Measurements and results Direct costs included inpatient, outpatient, pharmacy, and emergency room costs for all diseases, for six months before an index date. The index date for insomnia patients was the date of diagnosis with or the onset of prescription treatment for insomnia, some-time during July 1, 1999-June 30, 2003. Non-insomnia patients were assigned the same index dates as the insomnia patients to whom they were matched. Indirect costs included costs related to absenteeism from work and the use of short-term disability programs. Propensity score matching was used to find insomnia and non-insomnia patients who had similar demographics, location, health plan type, comorbidities, and drug use patterns. Regression analyses controlled for factors that were different even after matching was completed. We found that average direct and indirect costs for younger adults with insomnia were about $1,253 greater than for patients without insomnia. Among the elderly, direct costs were about $1,143 greater for insomnia patients. Conclusions Insomnia is associated with a significant economic burden for younger and older patients.

The Direct and Indirect Cost Burden of Crohn's Disease and Ulcerative Colitis

Abstract: Objective To estimate the direct medical and indirect (absenteeism and short-term disability) cost burden of Crohn's Disease (CD) and Ulcerative Colitis (UC). Methods Data were obtained from 1999 to 2005 MarketScan databases. Twelve-month expenditures for patients with CD and UC were compared to expenditures among an equal number of propensity score matched comparison group patients. Regression analysis controlled for demographics and case-mix. Results Annual medical expenditures were significantly higher for commercially insured CD and UC patients compared to matched comparison group patients ($18,963 vs $5300 for CD patients, $15,020 vs $4982 for UC patients, respectively, all P Conclusions CD and UC are costly diseases with a significant cost burden related to health care utilization and productivity loss.

Estimation and Inference in Econometrics

Abstract: Offering a unifying theoretical perspective not readily available in any other text, this innovative guide to econometrics uses simple geometrical arguments to develop students' intuitive understanding of basic and advanced topics, emphasizing throughout the practical applications of modern theory and nonlinear techniques of estimation. One theme of the text is the use of artificial regressions for estimation, reference, and specification testing of nonlinear models, including diagnostic tests for parameter constancy, serial correlation, heteroscedasticity, and other types of mis-specification. Explaining how estimates can be obtained and tests can be carried out, the authors go beyond a mere algebraic description to one that can be easily translated into the commands of a standard econometric software package. Covering an unprecedented range of problems with a consistent emphasis on those that arise in applied work, this accessible and coherent guide to the most vital topics in econometrics today is indispensable for advanced students of econometrics and students of statistics interested in regression and related topics. It will also suit practising econometricians who want to update their skills. Flexibly designed to accommodate a variety of course levels, it offers both complete coverage of the basic material and separate chapters on areas of specialized interest.

The Insomnia Severity Index: psychometric indicators to detect insomnia cases and evaluate treatment response.

Abstract: Background Although insomnia is a prevalent complaint with significant morbidity, it often remains unrecognized and untreated. Brief and valid instruments are needed both for screening and outcome assessment. This study examined psychometric indices of the Insomnia Severity Index (ISI) to detect cases of insomnia in a population-based sample and to evaluate treatment response in a clinical sample. Methods Participants were 959 individuals selected from the community for an epidemiological study of insomnia (Community sample) and 183 individuals evaluated for insomnia treatment and 62 controls without insomnia (Clinical sample). They completed the ISI and several measures of sleep quality, fatigue, psychological symptoms, and quality of life; those in the Clinical sample also completed sleep diaries, polysomnography, and interviews to validate their insomnia/good sleep status and assess treatment response. In addition to standard psychometric indices of reliability and validity, item response theory analyses were computed to examine ISI item response patterns. Receiver operating curves were used to derive optimal cutoff scores for case identification and to quantify the minimally important changes in relation to global improvement ratings obtained by an independent assessor. Results ISI internal consistency was excellent for both samples (Cronbach α of 0.90 and 0.91). Item response analyses revealed adequate discriminatory capacity for 5 of the 7 items. Convergent validity was supported by significant correlations between total ISI score and measures of fatigue, quality of life, anxiety, and depression. A cutoff score of 10 was optimal (86.1% sensitivity and 87.7% specificity) for detecting insomnia cases in the community sample. In the clinical sample, a change score of -8.4 points (95% CI: -7.1, -9.4) was associated with moderate improvement as rated by an independent assessor after treatment. Conclusion These findings provide further evidence that the ISI is a reliable and valid instrument to detect cases of insomnia in the population and is sensitive to treatment response in clinical patients.

Prevalence and co-occurrence of substance use disorders and independent mood and anxiety disorders: results from the National Epidemiologic Survey on Alcohol and Related Conditions.

Abstract: Background Uncertainties exist about the prevalence and comorbidity of substance use disorders and independent mood and anxiety disorders. Objective To present nationally representative data on the prevalence and comorbidity of DSM-IV alcohol and drug use disorders and independent mood and anxiety disorders (including only those that are not substance induced and that are not due to a general medical condition). Design Face-to-face survey. Setting The United States. Participants Household and group quarters' residents. Main Outcome Measures Prevalence and associations of substance use disorders and independent mood and anxiety disorders. Results The prevalences of 12-month DSM-IV independent mood and anxiety disorders in the US population were 9.21% (95% confidence interval [CI], 8.78%-9.64%) and 11.08% (95% CI, 10.43%-11.73%), respectively. The rate of substance use disorders was 9.35% (95% CI, 8.86%-9.84%). Only a few individuals with mood or anxiety disorders were classified as having only substance-induced disorders. Associations between most substance use disorders and independent mood and anxiety disorders were positive and significant ( P Conclusions Substance use disorders and mood and anxiety disorders that develop independently of intoxication and withdrawal are among the most prevalent psychiatric disorders in the United States. Associations between most substance use disorders and independent mood and anxiety disorders were overwhelmingly positive and significant, suggesting that treatment for a comorbid mood or anxiety disorder should not be withheld from individuals with substance use disorders.

Lifetime and 12-Month Prevalence of Bipolar Spectrum Disorder in the National Comorbidity Survey Replication

Abstract: The estimated lifetime prevalence of bipolar disorder (BPD) in population surveys using structured diagnostic interviews and standardized criteria averages approximately 0.8% for BP-I and 1.1% for BP-II.1-8 Despite this comparatively low prevalence, BPD is a leading cause of premature mortality due to suicide and associated medical conditions such as diabetes and cardiovascular disease.9, 10 BPD also causes widespread role impairment.11, 12 The recurrent nature of manic and depressive episodes often leads to high direct as well as high indirect health care costs.13, 14 BPD might be even more burdensome from a societal perspective due to the fact that sub-threshold bipolar spectrum disorder has seldom been taken into consideration in examining the epidemiology of BPD. Bipolar spectrum disorder includes hypomania without major depression and hypomania of lesser severity or briefer duration than specified in the DSM and ICD criteria. Although the precise definitions are as yet unclear, recent studies suggest that bipolar spectrum disorder might affect as many as 6% of the general population.15, 16 However, bipolar spectrum disorder has not been studied previously in a nationally representative survey of the US. The purpose of the current report is to present the results of such a study based on analysis of the National Comorbidity Survey Replication (NCS-R).17 We estimate prevalence and clinical features of sub-threshold BPD in comparison to BP-I and BP-II.