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Current Opinion on the Safety of Diagnostic Ultrasound
Published in Asim Kurjak, CRC Handbook of Ultrasound in Obstetrics and Gynecology, 2019
Probably the most serious limitation relates to the relatively small population size examined, which makes statistical analysis difficult. The likelihood of detecting a change depends on the relative increase in the incidence of the effect, and a small but important change requires study of a large population of exposed patients. The minimum sample size N needed to conclude that an observed increase is significant is given by
The Unicorn Industry Loses Its Wings
Published in Ruchin Kansal, Jeff Huth, Redefining Innovation, 2018
From a product innovation perspective, the industry has moved from tackling chronic diseases to specialty diseases to, more recently, rare diseases. It has looked at advances in genetics and genomics to become highly targeted in treatment efficacy. However, the disease states where a therapeutic product can provide competitive differentiation are getting more and more limited. There are over 7,000 known diseases, with only 5001 with treatments or cures, and therefore the case could be made that there is plenty of room for continued product-based innovation. However, look a little closer, and it is obvious that we are getting into the realm of very rare diseases, where due to the small population size it is very difficult to find patients to conduct trials and treatments. Furthermore, the expectation on margins leads to very high drug prices facing both affordability challenges (third-party payers and patients) plus a growing demand to demonstrate cost-effectiveness at a time when people are beginning to find the concept of societal rationing more acceptable even in the United States. These factors provide evidence that the current model will fail at some point. In fact, we would argue that the biopharmaceutical industry has no more than 30 years left of the traditional business model—ten more years for exhausting remaining white spaces that can be addressed purely with molecule-based products, and another 20 years of patent life protection. We are potentially being liberal here with the timeframe should new environmental challenges appear. Within this time, commoditization of the business model we know today will accelerate.
Epidemiology
Published in Samuel C. Morris, Cancer Risk Assessment, 2020
A relationship between leukemia and occupational exposure to benzene has been known since the 1920s, but detailed epidemiological studies were not begun until the 1970s (Infante and White, 1985). Because an animal model for benzene leukemogenicity was not available until the 1980s, risk assessment has been based almost entirely on epidemiology. Several epidemiology studies were initiated relying on historical data; three of these were the principal basis for EPA and OSHA standard setting in the late 1970s (Infante et al., 1977; Aksoy et al., 1974; Ott et al., 1978). These three studies and the EPA quantitative risk assessment are described by Bartman (1982). OSHA did not do a quantitative risk assessment, and its proposed regulation was invalidated by the U.S. Supreme Court when it was thus unable to estimate the cost per leukemia prevented. The basis for developing a quantitative dose-response function was sparse. Infante studied workers in a rubber film manufacturing process in Ohio. The study had limited exposure data, but showed a significant excess of leukemia in a population which had benzene as its principal exposure. The Aksoy study (1974) of Turkish shoe workers suffered similar problems to an even greater degree. There were few measurements of benzene in the workplace and since workers often lived in the same building as their shop, there may have been additional exposures outside of working hours. Furthermore, the cohort, although large, was not well defined. The Ott study (1978) had the best defined exposure estimates, but workers were also exposed to a range of other chemicals. Its major limitation was its small population size which led to statistical inconclusiveness.
Naturalistic follow-up study of rehospitalization rates and assigned disability status of patients with first-episode schizophrenia spectrum psychosis in South East Latvia: preliminary results
Published in Nordic Journal of Psychiatry, 2021
Liene Sile, Karina Bezina, Dmitrijs Kvartalovs, Renars Erts, Sarmite Kikuste, Inna Sapele, Elmars Rancans
We should emphasize that the results did not reach statistical significance. One of the main reasons being the weak statistical power because of the small population size. Therefore, we could not verify or reject the study hypothesis. The presented and discussed data should be read as preliminary analyses. Nevertheless, our results were intriguing in terms of its ability to show standard treatment outcomes in real-word settings and the need for more effective treatment approaches. A systematic review, meta-analysis, and meta-regression publication conducted by Correll et al. also proved that early intervention treatment was superior than treatment as usual in FEP patients [54]. We hope our results encourage policy makers in Latvia to implement early intervention approaches for first-episode psychosis patients.
Coping strategies used by patients with relapsing multiple sclerosis from Argentina: correlation with quality of life and clinical features
Published in Neurological Research, 2021
Edgar Carnero Contentti, Pablo A. López, Ricardo Alonso, Barbara Eizaguirre, Juan Pablo Pettinicchi, Santiago Tizio, Verónica Tkachuk, Alejandro Caride
Although the study is expected to contribute to knowledge about the role of coping strategies in PwMS and its relationship with clinical aspects and QoL, several limitations of this study should be noted. First, this was a cross-sectional study, and changes over time to investigate causality could not be evaluated. In addition, we used self-administrated questionnaires that tend to overestimate some values. Second, this was a research with a relatively small population size compared with other cohorts worldwide. However, MS has an estimated prevalence of 38.2 of 100,000 inhabitants in Buenos Aires, Argentina [39]. Third, we had a relatively lower response rate, since only around 15% of PwMS invited to participate completed the questionnaire. One possible explanation is related to questionnaire distribution method: it cannot be known with certainty how many people received the invitation as it was an online survey sent by email through a patient association (ALCEM members). Another possible reason is that PwMS could be reluctant to talk about their disease, either due to lack of interest or because of stress related to this topic. Fourth, we did not evaluate cognitive impairment, anxiety, and depression, which could interact with the use of coping strategies. Despite these limitations, we consider that this is a valuable first study about coping in Latin American PwMS, and its relationship with different aspects of the disease that are highly relevant to be considered in clinical practice.
The clinical and economic burden of cytomegalovirus management post allogeneic hematopoietic stem cell transplantation in Japan – a retrospective database study
Published in Current Medical Research and Opinion, 2019
Rie Ueno, Shinichi Nishimura, Go Fujimoto, Yi Piao, Katsuto Takenaka
CMV reactivation is not only associated with negative clinical outcome, but also correlated with increased economic burden. Previously, a single-site study in the US compared outcomes and post-transplant treatment cost between 44 patients who never required PET and 90 treated patients undergoing allo-HSCT. Those patients who required PET incurred an additional cost of antiviral medication ($58,000–$74,000 per patient), and additional days of hospitalization (13.9 days per patient)12. On the other hand, a recent French single-institution study also examined an association between CMV reactivation and cost incurred post allo-HSCT in 208 adult patients. In this study, the cost of transplant after 12 months increased with the number of CMV episodes (€99,793, €104,815, and €125,080 with no CMV episode, 1 CMV episode, and ≥2 CMV episodes, respectively)13. However, those previous studies were limited by a small population size and lack of details of healthcare resource utilization incurred after transplantation.