Improving customer churn prediction by data augmentation using pictorial stimulus-choice data

The purpose of this paper is to determine the added value of pictorial stimulus-choice data in customer churn prediction. Using Random Forests and 5 times 2 fold cross-validation, this study analyzes how much pictorial stimulus choice data and survey data increase the AUC of a churn model over and above administrative, operational and complaints data. The finding is that pictorial-stimulus choice data significantly increases AUC of models with administrative and operational data. The practical implication of this finding is that companies should start considering mining pictorial data from social media sites (e.g. Pinterest), in order to augment their internal customer database. This study is original in that it is the first that assesses the added value of pictorial stimulus-choice data in predictive models. This is important because more and more social media websites are focusing on pictures

Re-resectie bij longtuberculose:een klinisch-morphologische studie, gebaseerd op 42 gevallen waarbij resectiebehandeling gefaald heeft, voorafgegaan door een vergelijkend statistisch onderzoek over complicaties, waargenomen bij 100 patiënten in een periode van 4 tot 6 jaren na de longresectie

In de inleiding zijn doel en inhoud van dit proefschrift uiteengezet. Een onderzoek naar de betekenis van de reresectie van longweefsel bij de chirurgische behandeling van longtuberculose vormde het hoofdmotief. Aan de beperktheid van de te behandelen stof is een uitbreiding gegeven ten einde op een viertal vragen het antwoord te vinden. .... Zie: Samenvattin

Bacterial dichloropropene degradation in soil:Screening of soils and involvement of plasmids carrying the dhlA gene

The nematocide cis-1,3-dichloropropene is widely used in intensive agricultural practice against root knot nematodes. As a result of the regular application of dichloropropene to six out of eight different soils, the compound was rapidly degraded to CO2, H2O and chloride ions in subsequent applications (adapted soils). Such degradation occurred at a lower rate in the same soil types without a history of dichloropropene use (unadapted soils). In two soils, the effect of repeated dichloropropene treatment was not found, since dichloropropene was already rapidly decomposed in the untreated controls. Since the dehalogenating enzyme haloalkane dehalogenase, encoded by the dhlA gene, is possibly involved in the degradation of dichloropropene, a specific PCR detection system combined with a dhlA probe was developed to detect dhlA in soil DNA extracts. Five of the eight adapted soils as well as three unadapted ones showed a response to this system, indicating the presence of DNA with sequence similarity to dhlA. Fifteen bacterial strains with dichloropropene-degradative capacity were isolated from enrichment cultures grown in the presence of this compound and inoculated with adapted soil (five soil types). Six selected isolates were identified as, respectively, Alcaligenes paradoxus, Pseudomonas cichorii I, Pseudomonas corrugata (2 x), Pseudomonas putida and Pseudomonas sp. Each of the six strains harboured a plasmid of 50-60 kb in size and all but one carried resistance to HgCl2. Filter matings were performed to investigate the possible cotransfer of biodegradative genes and Hg resistance to suitably-marked P. fluorescens R2f recipient strains. Three plasmid donor strains, P. cichorii I, P. corrugata and Pseudomonas sp., transferred the Hg resistance and the plasmid to the recipient used, suggesting that the Hg resistance marker was located on the plasmid. In addition, transconjugants produced with P. cichorii I and P. corrugata donor strains had also acquired 1,3-dichloropropene-degrading capability. PCR amplification with dhlA specific primers, of the plasmids obtained both from the original P. cichorii I and P. corrugata strains and from the respective transconjugant P. fluorescens R2f strains generated 400-500 bp amplification products. After cloning of the product of the P. cichorii I plasmid and sequencing of 180 bases, extensive homology with the dhlA gene was detected. These results suggest that a plasmid-located dhlA-like gene may be involved in dichloropropene degradation in soil by soil bacteria, but the extent to which the gene is involved in the process in situ is not clear.</p

Children’s route choice during active transportation to school: difference between shortest and actual route

BackgroundThe purpose of this study is to increase our understanding of environmental correlates that are associated with route choice during active transportation to school (ATS) by comparing characteristics of actual walking and cycling routes between home and school with the shortest possible route to school.MethodsChildren (n = 184; 86 boys, 98 girls; age range: 8–12 years) from seven schools in suburban municipalities in the Netherlands participated in the study. Actual walking and cycling routes to school were measured with a GPS-device that children wore during an entire school week. Measurements were conducted in the period April–June 2014. Route characteristics for both actual and shortest routes between home and school were determined for a buffer of 25m from the routes and divided into four categories: Land use (residential, commercial, recreational, traffic areas), Aesthetics (presence of greenery/natural water ways along route), Traffic (safety measures such as traffic lights, zebra crossings, speed bumps) and Type of street (pedestrian, cycling, residential streets, arterial roads). Comparison of characteristics of shortest and actual routes was performed with conditional logistic regression models.ResultsMedian distance of the actual walking routes was 390.1m, whereas median distance of actual cycling routes was 673.9m. Actual walking and cycling routes were not significantly longer than the shortest possible routes. Children mainly traveled through residential areas on their way to school (>80% of the route). Traffic lights were found to be positively associated with route choice during ATS. Zebra crossings were less often present along the actual routes (walking: OR = 0.17, 95 % CI = 0.05–0.58; cycling: OR = 0.31, 95 % CI = 0.14–0.67), and streets with a high occurrence of accidents were less often used during cycling to school (OR = 0.57, 95% CI = 0.43–0.76). Moreover, percentage of visible surface water along the actual route was higher compared to the shortest routes (walking: OR = 1.04, 95 % CI = 1.01–1.07; cycling: OR = 1.03, 95 % CI = 1.01–1.05).DiscussionThis study showed a novel approach to examine built environmental exposure during active transport to school. Most of the results of the study suggest that children avoid to walk or cycle along busy roads on their way to school.Electronic supplementary materialThe online version of this article (doi:10.1186/s12966-016-0373-y) contains supplementary material, which is available to authorized users

Outcomes After Major Surgical Procedures in Octogenarians:A Nationwide Cohort Study

Introduction: Aging of the worldwide population has been observed, and postoperative outcomes could be worse in elderly patients. This nationwide study assessed trends in number of surgical resections in octogenarians regarding various major surgical procedures and associated postoperative outcomes. Methods: All patients who underwent surgery between 2014 and 2018 were included from Dutch nationwide quality registries regarding esophageal, stomach, pancreas, colorectal liver metastases, colorectal cancer, lung cancer and abdominal aortic aneurysms (AAA). For each quality registry, the number of patients who were 80 years or older (octogenarians) was calculated per year. Postoperative outcomes were length of stay (LOS), 30 day major morbidity and 30 day mortality between octogenarians and younger patients. Results: No increase in absolute number and proportion of octogenarians that underwent surgery was observed. Median LOS was higher in octogenarians who underwent surgery for colorectal cancer, colorectal liver metastases, lung cancer, pancreatic disease and esophageal cancer. 30 day major morbidity was higher in octogenarians who underwent surgery for colon cancer, esophageal cancer and elective AAA-repair. 30 day mortality was higher in octogenarians who underwent surgery for colorectal cancer, lung cancer, stomach cancer, pancreatic disease, esophageal cancer and elective AAA-repair. Median LOS decreased between 2014 and 2018 in octogenarians who underwent surgery for stomach cancer and colorectal cancer. 30 day major morbidity decreased between 2014 and 2018 in octogenarians who underwent surgery for colon cancer. No trends were observed in octogenarians regarding 30 day mortality between 2014 and 2018. Conclusion: No increase over time in absolute number and proportion of octogenarians that underwent major surgery was observed in the Netherlands. Postoperative outcomes were worse in octogenarians

The COSMIN checklist for assessing the methodological quality of studies on measurement properties of health status measurement instruments: an international Delphi study

BACKGROUND: Aim of the COSMIN study (COnsensus-based Standards for the selection of health status Measurement INstruments) was to develop a consensus-based checklist to evaluate the methodological quality of studies on measurement properties. We present the COSMIN checklist and the agreement of the panel on the items of the checklist. METHODS: A four-round Delphi study was performed with international experts (psychologists, epidemiologists, statisticians and clinicians). Of the 91 invited experts, 57 agreed to participate (63%). Panel members were asked to rate their (dis)agreement with each proposal on a five-point scale. Consensus was considered to be reached when at least 67% of the panel members indicated 'agree' or 'strongly agree'. RESULTS: Consensus was reached on the inclusion of the following measurement properties: internal consistency, reliability, measurement error, content validity (including face validity), construct validity (including structural validity, hypotheses testing and cross-cultural validity), criterion validity, responsiveness, and interpretability. The latter was not considered a measurement property. The panel also reached consensus on how these properties should be assessed. CONCLUSIONS: The resulting COSMIN checklist could be useful when selecting a measurement instrument, peer-reviewing a manuscript, designing or reporting a study on measurement properties, or for educational purposes.This study was financially supported by the EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, and the Anna Foundation, Leiden, The Netherlands

Effectiveness of a questionnaire based intervention programme on the prevalence of arm, shoulder and neck symptoms, risk factors and sick leave in computer workers: A cluster randomised controlled trial in an occupational setting

<p>Abstract</p> <p>Background</p> <p>Arm, shoulder and neck symptoms are very prevalent among computer workers. In an attempt to reduce these symptoms, a large occupational health service in the Netherlands developed a preventive programme on exposure to risk factors, prevalence of arm, shoulder and neck symptoms, and sick leave in computer workers. The purpose of this study was to assess the effectiveness of this intervention programme.</p> <p>Methods</p> <p>The study was a randomised controlled trial. The participants were assigned to either the intervention group or the usual care group by means of cluster randomisation. At baseline and after 12 months of follow-up, the participants completed the RSI QuickScan questionnaire on exposure to the risk factors and on the prevalence of arm, shoulder and neck symptoms. A tailor-made intervention programme was proposed to participants with a high risk profile at baseline. Examples of implemented interventions are an individual workstation check, a visit to the occupational health physician and an education programme on the prevention of arm, shoulder and neck symptoms. The primary outcome measure was the prevalence of arm, shoulder and neck symptoms. Secondary outcome measures were the scores on risk factors for arm, shoulder and neck symptoms and the number of days of sick leave. Sick leave data was obtained from the companies. Multilevel analyses were used to test the effectiveness.</p> <p>Results</p> <p>Of the 1,673 persons invited to participate in the study, 1,183 persons (71%) completed the baseline questionnaire and 741 persons participated at baseline as well as at 12-month follow-up. At 12-month follow-up, the intervention group showed a significant positive change (OR = 0.48) in receiving information on healthy computer use, as well as a significant positive change regarding risk indicators for work posture and movement, compared to the usual care group. There were no significant differences in changes in the prevalence of arm, shoulder and neck symptoms or sick leave between the intervention and usual care group.</p> <p>Conclusions</p> <p>The effects of the RSI QuickScan intervention programme were small, possibly as a result of difficulties with the implementation process of the proposed interventions. However, some significant positive effects were found as to an increase in receiving education and a decrease in exposure to adverse postures and movements. With regard to symptoms and sick leave, only small and non-significant effects were found.</p> <p>Trial registration</p> <p>Netherlands National Trial Register NTR1117</p

SARS-CoV-2 outbreaks in secondary school settings in the Netherlands during fall 2020: silent circulation

BACKGROUND: In fall 2020 when schools in the Netherlands operated under a limited set of COVID-19 measures, we conducted outbreaks studies in four secondary schools to gain insight in the level of school transmission and the role of SARS-CoV-2 transmission via air and surfaces. METHODS: Outbreak studies were performed between 11 November and 15 December 2020 when the wild-type variant of SARS-CoV-2 was dominant. Clusters of SARS-CoV-2 infections within schools were identified through a prospective school surveillance study. All school contacts of cluster cases, irrespective of symptoms, were invited for PCR testing twice within 48 h and 4-7 days later. Combined NTS and saliva samples were collected at each time point along with data on recent exposure and symptoms. Surface and active air samples were collected in the school environment. All samples were PCR-tested and sequenced when possible. RESULTS: Out of 263 sampled school contacts, 24 tested SARS-CoV-2 positive (secondary attack rate 9.1%), of which 62% remained asymptomatic and 42% had a weakly positive test result. Phylogenetic analysis on 12 subjects from 2 schools indicated a cluster of 8 and 2 secondary cases, respectively, but also other distinct strains within outbreaks. Of 51 collected air and 53 surface samples, none were SARS-CoV-2 positive. CONCLUSION: Our study confirmed within school SARS-CoV-2 transmission and substantial silent circulation, but also multiple introductions in some cases. Absence of air or surface contamination suggests environmental contamination is not widespread during school outbreaks