Treating childhood cancer in Rwanda: the nephroblastoma example

Introduction: Wilms tumor (WT) or nephroblastoma is the commonest childhood cancer in Rwanda. Nephroblastoma is regarded as one of the successes of pediatric oncology with long-term survival approaching 90%. The Objectives to evaluate the feasibilityof treating childhood cancer using the nephroblastoma example and to calculate its cost of treatment in Rwanda. Methods: Prospective study over a 2 year period: 01 Jan 2010- 31 December 2011.A questionnaire was completed by all participants in the study and the following variables were collected at Kigali University Teaching Hospital: age at diagnosis, gender, transport cost, cost of investigations, staging, treatment and outcome, cost of hospitalization, type of medical, surgical, radiological interventions and their costs, number of admissions per patient and factors related to non compliance to treatment. All patients had a confirmed diagnosis on histopathology examination. The cost for treatment was calculated for early and late stage and was expressed in USA dollars. Analysis was done with SPSS 16.0. Results: There were 25 patients diagnosed and treated for WT during the study period. Almost half of the patients 14/25 (56%) had advanced disease, seven children (28%) had stage IV, seven children stage III, six patients (24%) with stage II, while the remaining five (20%) had stage I with high risk tumor. The direct cost of management ranged from1,831.2 USD for early disease to 2,418.7 USD for advanced disease. The cost of transport, investigations and drugs were recorded as main contributing factors to the feasibility and cost of the treatment in 80% of the responses, followed by late presentation (56%) and poor compliance to treatment. Conclusion: Most challenges are related to unaffordable treatment and late presentation. The management of WT is feasible in Rwandan setting but efforts should be made in order to improve awareness of childhood cancer, early diagnosis and access to care. The government of Rwanda is committed to improve cancer care in the country and organized the first pediatric international oncology conference in Kigali, in March 2012 to develop National protocols for the top five most common cancers in children

Efficiency in sequential testing: Comparing the sequential probability ratio test and the sequential Bayes factor test

In a sequential hypothesis test, the analyst checks at multiple steps during data collection whether sufficient evidence has accrued to make a decision about the tested hypotheses. As soon as sufficient information has been obtained, data collection is terminated. Here, we compare two sequential hypothesis testing procedures that have recently been proposed for use in psychological research: Sequential Probability Ratio Test (SPRT; Psychological Methods, 25(2), 206–226, 2020) and the Sequential Bayes Factor Test (SBFT; Psychological Methods, 22(2), 322–339, 2017). We show that although the two methods have different philosophical roots, they share many similarities and can even be mathematically regarded as two instances of an overarching hypothesis testing framework. We demonstrate that the two methods use the same mechanisms for evidence monitoring and error control, and that differences in efficiency between the methods depend on the exact specification of the statistical models involved, as well as on the population truth. Our simulations indicate that when deciding on a sequential design within a unified sequential testing framework, researchers need to balance the needs of test efficiency, robustness against model misspecification, and appropriate uncertainty quantification. We provide guidance for navigating these design decisions based on individual preferences and simulation-based design analyses