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Causal Impact (causal + impact)
Selected AbstractsThe relation between different dimensions of alcohol consumption and burden of disease: an overviewADDICTION, Issue 5 2010Jürgen Rehm ABSTRACT Aims As part of a larger study to estimate the global burden of disease and injury attributable to alcohol: to evaluate the evidence for a causal impact of average volume of alcohol consumption and pattern of drinking on diseases and injuries; to quantify relationships identified as causal based on published meta-analyses; to separate the impact on mortality versus morbidity where possible; and to assess the impact of the quality of alcohol on burden of disease. Methods Systematic literature reviews were used to identify alcohol-related diseases, birth complications and injuries using standard epidemiological criteria to determine causality. The extent of the risk relations was taken from meta-analyses. Results Evidence of a causal impact of average volume of alcohol consumption was found for the following major diseases: tuberculosis, mouth, nasopharynx, other pharynx and oropharynx cancer, oesophageal cancer, colon and rectum cancer, liver cancer, female breast cancer, diabetes mellitus, alcohol use disorders, unipolar depressive disorders, epilepsy, hypertensive heart disease, ischaemic heart disease (IHD), ischaemic and haemorrhagic stroke, conduction disorders and other dysrhythmias, lower respiratory infections (pneumonia), cirrhosis of the liver, preterm birth complications and fetal alcohol syndrome. Dose,response relationships could be quantified for all disease categories except for depressive disorders, with the relative risk increasing with increased level of alcohol consumption for most diseases. Both average volume and drinking pattern were linked causally to IHD, fetal alcohol syndrome and unintentional and intentional injuries. For IHD, ischaemic stroke and diabetes mellitus beneficial effects were observed for patterns of light to moderate drinking without heavy drinking occasions (as defined by 60+ g pure alcohol per day). For several disease and injury categories, the effects were stronger on mortality compared to morbidity. There was insufficient evidence to establish whether quality of alcohol had a major impact on disease burden. Conclusions Overall, these findings indicate that alcohol impacts many disease outcomes causally, both chronic and acute, and injuries. In addition, a pattern of heavy episodic drinking increases risk for some disease and all injury outcomes. Future studies need to address a number of methodological issues, especially the differential role of average volume versus drinking pattern, in order to obtain more accurate risk estimates and to understand more clearly the nature of alcohol,disease relationships. [source] Locus of control and the flow experience: An experimental analysisEUROPEAN JOURNAL OF PERSONALITY, Issue 7 2008Johannes Keller Abstract The present research addresses the notion that the compatibility of skills and task demands involved in a given activity elicits a flow experience that renders the respective activity rewarding. The study employed an experimental paradigm to document the causal impact of skills,demands compatibility on the emergence of flow and revealed that participants characterized by a strong internal locus of control (LOC) were most sensitive to the manipulation of skills,demands compatibility and experienced flow under conditions of a fit of skills and task demands, whereas individuals with a weak internal LOC did not enter the state of flow. In line with previous findings, this suggests that distinct personality attributes are of critical relevance for the experience of flow to emerge. Copyright © 2008 John Wiley & Sons, Ltd. [source] The impact of state physical education requirements on youth physical activity and overweightHEALTH ECONOMICS, Issue 12 2007John Cawley Abstract To combat childhood overweight in the US, which has risen dramatically in the past three decades, many medical and public health organizations have called for students to spend more time in physical education (PE) classes. This paper is the first to examine the impact of state PE requirements on student PE exercise time. It also exploits variation in state laws as quasi-natural experiments in order to estimate the causal impact of PE on overall student physical activity and weight. We study nationwide data from the Youth Risk Behavior Surveillance System for 1999, 2001, and 2003 merged with data on state minimum PE requirements from the 2001 Shape of the Nation Report. We find that high school students with a binding PE requirement report an average of 31 additional minutes per week spent physically active in PE class. Our results also indicate that additional PE time raises the number of days per week that girls report having exercised vigorously or having engaged in strength-building activity. We find no evidence that PE lowers BMI or the probability that a student is overweight. We conclude that raising PE credit requirements may make girls more physically active overall but there is not yet the scientific base to declare raising PE requirements an anti-obesity initiative for either boys or girls. Copyright © 2007 John Wiley & Sons, Ltd. [source] Estimating treatment effects in randomized clinical trials with non-compliance: the impact of maternal smoking on birthweightHEALTH ECONOMICS, Issue 5 2001Barton H. Hamilton Abstract This paper assesses the causal impact of late-term (8th month) maternal smoking on birthweight using data from a randomized clinical trial, in which some women were encouraged not to smoke, while others were not. The estimation of treatment effects in this case is made difficult as a result of the presence of non-compliers, women who would not change their smoking status, regardless of the receipt of encouragement. Because these women are not at risk of changing treatment status, treatment effect distributions may be difficult to construct for them. Consequently, the paper focuses on obtaining the distribution of treatment impacts for the sub-set of compliers found in the data. Because compliance status is not observed for all subjects in the sample, a Bayesian finite mixture model is estimated that recovers the treatment effect parameters of interest. The complier average treatment effect implies that smokers give birth to infants weighing 348 g less than those of non-smokers, on average, although the 95% posterior density interval contains zero. The treatment effect is stronger for women who were moderate smokers prior to pregnancy, implying a birthweight difference of 430 g. However, the model predicts that only about 22% of the women in the sample were at risk of changing their smoking behaviour in response to encouragement to quit. Copyright © 2001 John Wiley & Sons, Ltd. [source] The development and resulting performance impact of positive psychological capitalHUMAN RESOURCE DEVELOPMENT QUARTERLY, Issue 1 2010Fred Luthans Recently, theory and research have supported psychological capital (PsyCap) as an emerging core construct linked to positive outcomes at the individual and organizational level. However, to date, little attention has been given to PsyCap development through training interventions; nor have there been attempts to determine empirically if such PsyCap development has a causal impact on participants' performance. To fill these gaps we first conducted a pilot test of the PsyCap intervention (PCI) model with a randomized control group design. Next, we conducted a follow-up study with a cross section of practicing managers to determine if following the training guidelines of the PCI caused the participants' performance to improve. Results provide beginning empirical evidence that short training interventions such as PCI not only may be used to develop participants' psychological capital, but can also lead to an improvement in their on-the-job performance. The implications these findings have for human resource development and performance management conclude the article. [source] New Technology in Schools: Is There a Payoff?,THE ECONOMIC JOURNAL, Issue 522 2007Stephen Machin Despite its high relevance to current policy debates, estimating the causal effect of Information and Communication Technology (ICT) investment on educational standards remains fraught with difficulties. We exploit a change in the rules governing ICT funding across different school districts of England to devise an Instrumental Variable strategy to identify the causal impact of ICT expenditure on pupil outcomes. The approach identifies the effect of being a ,winner' or a ,loser' in the new system of ICT funding allocation to schools. Our findings suggest a positive impact on primary school performance in English and Science, though not for Mathematics. [source] Hyponatremia in Heart Failure: Revisiting Pathophysiology and Therapeutic StrategiesCLINICAL CARDIOLOGY, Issue 6 2010Amir Kazory MD Hyponatremia is frequently encountered in patients with heart failure (HF), and its association with adverse outcomes is well-established in this population. While hyponatremia is an independent marker for severity of HF, it is not certain whether it has a causal impact on the progression of the disease. There are no universally accepted consensus guidelines regarding therapeutic strategies for HF-associated hyponatremia and volume overload; current societal guidelines do not address management of this complication. Whereas thiazide diuretics are known to induce or worsen hyponatremia in this setting through a number of mechanisms, loop diuretics can be considered a readily available first-line pharmacologic therapy. Consistent with pathophysiology of the disease and mechanisms of action of loop diuretics, available clinical evidence supports such an approach provided that patients can be closely monitored. Use of vasopressin receptor antagonists is an emerging therapeutic strategy in this setting, and the efficacy of these agents has so far been shown in a number of clinical studies. These agents can be reserved for patients with HF in whom initial appropriate loop diuretic therapy fails to improve serum sodium levels. Copyright © 2010 Wiley Periodicals, Inc. [source] THE CORRELATION OF YOUTH PHYSICAL ACTIVITY WITH STATE POLICIESCONTEMPORARY ECONOMIC POLICY, Issue 4 2007JOHN CAWLEY Childhood overweight has risen dramatically in the United States during the past three decades. The search for policy solutions is limited by a lack of evidence regarding the effectiveness of state policies for increasing physical activity among youths. This paper estimates the correlation of student physical activity with a variety of state policies. We study nationwide data on high school students from the Youth Risk Behavior Surveillance System for 1999, 2001, and 2003 merged with data on state policies from several sources. We control for a variety of characteristics of states and students to mitigate bias due to the endogenous selection of policies, but we conservatively interpret our results as correlations, not causal impacts. Two policies are positively correlated with participation in physical education (PE) class for both boys and girls: a binding PE unit requirement and a state PE curriculum. We also find that state spending on parks and recreation is positively correlated with two measures of girls' overall physical activity. (JEL I18, I28) [source] | |||||||||||||