Dynamics and Competition in Charitable Giving

Nowadays potential donors receive many direct mailings from many different charities, all soliciting their donations. As charities depend for a large part on their revenues from direct mail it is important to uncover the precise effects of charitable direct mailings on donating behavior. Existing studies on donating behavior generally focus on a single decision context, that is, a single donation to a single charitable cause. In reality, however, people receive many donation requests, and the responses to these requests may not be independent. In this thesis we study the dynamic and competitive effects of charitable direct mailings on donating behavior. We present two direct mailing response models, with the first focusing primarily on the competitive dimension, and the second focusing mainly on the dynamic dimension. To calibrate these models we have access to a unique dataset consisting of the databases of multiple charity organizations, providing us wi

Do Charities Get More when They Ask More Often? Evidence from a Unique Field Experiment

Charitable organizations send out large volumes of direct mailings, soliciting for money in support of many good causes. Without any request, donations are rarely made, and it is well known that each request for money by a charity likely generates at least some revenues. Whether a single request from a charity increases the total amount donated by an individual is however unknown. Indeed, a response to one request can hurt responses to others. The net effect is therefore not easily observable, certainly not when multiple charities address the same individuals. In this paper we alleviate these observational difficulties by carrying out a field experiment in which five large charities cooperate. With the unique data that we collect, we study the impact of sending more requests on total donations. The results indicate that there is a negative competitive effect on requests from other charities, but this effect dies out rapidly. Soon after the mailing has been sent, it is only a strong cannibalization of the charity’s own revenues that prevails. This empirical finding suggests the important conclusion that not much coordination across charities is needed to increase revenues. We also demonstrate that charities need sophisticated evaluation tools that do not ignore the effects of cannibalization

Does Irritation Induced by Charitable Direct Mailings Reduce Donations?

Charities mainly rely on direct mailings to attract the attention of potential donators. Individuals may feel irritated by these mailings, in particular when they receive many mailings. We study the consequences of perceived irritation on stated behavior and on actual behavior. Target selection by charities likely results in good donators receiving many mailings and hence they might also be most irritated. Therefore, irritation with direct mailings might be endogenously determined. To create exogenous variation in irritation, we design a unique controlled field experiment in cooperation with five of the largest charities in the Netherlands. Our analysis reveals that direct mailings do result in irritation, but surprisingly this affects neither stated nor actual donating behavior

Meer betaalgemak door de euro.

De euro geeft meer betaalgemak dan de gulden. Empirisch onderzoek laat zien dat Nederlanders efficiënter dan in het guldentijdperk betalen met de reeks van eurobiljetten en -munten. Ook heeft men - in tegenstelling tot de gulden - geen sterke voorkeur voor bepaalde coupures

Prediction meets causal inference: the role of treatment in clinical prediction models

In this paper we study approaches for dealing with treatment when developing a clinical prediction model. Analogous to the estimand framework recently proposed by the European Medicines Agency for clinical trials, we propose a ‘predictimand’ framework of different questions that may be of interest when predicting risk in relation to treatment started after baseline. We provide a formal definition of the estimands matching these questions, give examples of settings in which each is useful and discuss appropriate estimators including their assumptions. We illustrate the impact of the predictimand choice in a dataset of patients with end-stage kidney disease. We argue that clearly defining the estimand is equally important in prediction research as in causal inference

Publisher Correction: Lower body mass index and mortality in older adults starting dialysis (vol 8, 12858, 2018)

Clinical epidemiolog

Performance of Cardiovascular Disease Risk Scores in People Diagnosed With Type 2 Diabetes:External Validation Using Data From the National Scottish Diabetes Register

Objective: To evaluate the performance of five cardiovascular disease (CVD) risk scores developed in diabetes populations and compare their performance to QRISK2. Research Design and Methods: A cohort of people diagnosed with type 2 diabetes between 2004 and 2016 was identified from the Scottish national diabetes register. CVD events were identified using linked hospital and death records. Five-year risk of CVD was estimated using each of QRISK2, ADVANCE (Action in Diabetes and Vascular disease: preterAx and diamicroN-MR Controlled Evaluation), Cardiovascular Health Study (CHS), New Zealand Diabetes Cohort Study (NZ DCS), Fremantle Diabetes Study, and Swedish National Diabetes Register (NDR) risk scores. Discrimination and calibration were assessed using the Harrell C statistic and calibration plots, respectively. Results: The external validation cohort consisted of 181,399 people with type 2 diabetes and no history of CVD. There were 14,081 incident CVD events within 5 years of follow-up. The 5-year observed risk of CVD was 9.7% (95% CI 9.6, 9.9). C statistics varied between 0.66 and 0.67 for all risk scores. QRISK2 overestimated risk, classifying 87% to be at high risk for developing CVD within 5 years; ADVANCE underestimated risk, and the Swedish NDR risk score calibrated well to observed risk. Conclusions: None of the risk scores performed well among people with newly diagnosed type 2 diabetes. Using these risk scores to predict 5-year CVD risk in this population may not be appropriate

Lower body mass index and mortality in older adults starting dialysis

Lower body mass index (BMI) has consistently been associated with mortality in elderly in the general and chronic disease populations. Remarkably, in older incident dialysis patients no association of BMI with mortality was found. We performed an in-depth analysis and explored possible time-stratified effects of BMI. 908 incident dialysis patients aged >= 65 years of the NECOSAD study were included, and divided into tertiles by baseline BMI (<23.1 ( lower), 23.1-26.0 ( reference), >= 26.0 (higher) kg/ m(2)). Because the hazards changed significantly during follow-up, the effect of BMI was modeled for the short-term (<1 year) and longer-term (>= 1 year after dialysis initiation). During follow-up (median 3.8 years) 567 deaths occurred. Lower BMI was associated with higher short-term mortality risk (adjusted-HR 1.63 [1.14-2.32] P = 0.007), and lower longer-term mortality risk (adjusted-HR 0.81 [0.63- 1.04] P = 0.1). Patients with lower BMI who died during the first year had significantly more comorbidity, and worse self-reported physical functioning compared with those who survived the first year. Thus, lower BMI is associated with increased 1-year mortality, but conditional on surviving the first year, lower BMI yielded a similar or lower mortality risk compared with the reference. Those patients with lower BMI, who had limited comorbidity and better physical functioning, had better survival

Stopping renin-angiotensin system blockers after acute kidney injury and risk of adverse outcomes: parallel population-based cohort studies in English and Swedish routine care.

BACKGROUND: The safety of restarting angiotensin-converting enzyme inhibitors (ACEI) or angiotensin II receptor blockers (ARB) after acute kidney injury (AKI) is unclear. There is concern that previous users do not restart ACEI/ARB despite ongoing indications. We sought to determine the risk of adverse events after an episode of AKI, comparing prior ACEI/ARB users who stop treatment to those who continue. METHODS: We conducted two parallel cohort studies in English and Swedish primary and secondary care, 2006-2016. We used multivariable Cox regression to estimate hazard ratios (HR) for hospital admission with heart failure (primary analysis), AKI, stroke, or death within 2 years after hospital discharge following a first AKI episode. We compared risks of admission between people who stopped ACEI/ARB treatment to those who were prescribed ACEI/ARB within 30 days of AKI discharge. We undertook sensitivity analyses, including propensity score-matched samples, to explore the robustness of our results. RESULTS: In England, we included 7303 people with AKI hospitalisation following recent ACEI/ARB therapy for the primary analysis. Four thousand three (55%) were classified as stopping ACEI/ARB based on no prescription within 30 days of discharge. In Sweden, we included 1790 people, of whom 1235 (69%) stopped treatment. In England, no differences were seen in subsequent risk of heart failure (HR 1.10; 95% confidence intervals (CI) 0.93-1.30), AKI (HR 0.90; 95% CI 0.77-1.05), or stroke (HR 0.99; 95% CI 0.71-1.38), but there was an increased risk of death (HR 1.27; 95% CI 1.15-1.41) in those who stopped ACEI/ARB compared to those who continued. Results were similar in Sweden: no differences were seen in risk of heart failure (HR 0.91; 95% CI 0.73-1.13) or AKI (HR 0.81; 95% CI 0.54-1.21). However, no increased risk of death was seen (HR 0.94; 95% CI 0.78-1.13) and stroke was less common in people who stopped ACEI/ARB (HR 0.56; 95% CI 0.34-0.93). Results were similar across all sensitivity analyses. CONCLUSIONS: Previous ACEI/ARB users who continued treatment after an episode of AKI did not have an increased risk of heart failure or subsequent AKI compared to those who stopped the drugs

Associations between depressive symptoms and disease progression in older patients with chronic kidney disease: results of the EQUAL study

Background Depressive symptoms are associated with adverse clinical outcomes in patients with end-stage kidney disease; however, few small studies have examined this association in patients with earlier phases of chronic kidney disease (CKD). We studied associations between baseline depressive symptoms and clinical outcomes in older patients with advanced CKD and examined whether these associations differed depending on sex. Methods CKD patients (&gt;= 65 years; estimated glomerular filtration rate &lt;= 20 mL/min/1.73 m(2)) were included from a European multicentre prospective cohort between 2012 and 2019. Depressive symptoms were measured by the five-item Mental Health Inventory (cut-off &lt;= 70; 0-100 scale). Cox proportional hazard analysis was used to study associations between depressive symptoms and time to dialysis initiation, all-cause mortality and these outcomes combined. A joint model was used to study the association between depressive symptoms and kidney function over time. Analyses were adjusted for potential baseline confounders. Results Overall kidney function decline in 1326 patients was -0.12 mL/min/1.73 m(2)/month. A total of 515 patients showed depressive symptoms. No significant association was found between depressive symptoms and kidney function over time (P = 0.08). Unlike women, men with depressive symptoms had an increased mortality rate compared with those without symptoms [adjusted hazard ratio 1.41 (95% confidence interval 1.03-1.93)]. Depressive symptoms were not significantly associated with a higher hazard of dialysis initiation, or with the combined outcome (i.e. dialysis initiation and all-cause mortality). Conclusions There was no significant association between depressive symptoms at baseline and decline in kidney function over time in older patients with advanced CKD. Depressive symptoms at baseline were associated with a higher mortality rate in men