17 research outputs found
Budget impact analysis of medicines : updated systematic review and implications
This evaluation determines whether published studies to date meet the key characteristics identified for budget impact analyses (BIA) for medicines, accomplished through a systematic review and assessment against identified key characteristics. Studies from 2001 to 2015 on "budget impact analysis" with "drug" interventions were assessed, selected based on their titles/abstracts and full texts, with their characteristics checked according to key criteria. Out of 1984 studies, 92 were identified. Of these, 95% were published in Europe and the USA. 2012 saw the largest number of publications (16%) with a decline thereafter. 48% met up to 6 or 7 out of the 9 key characteristics. Only 22% stated no conflict of interest. The results indicate low adherence to the key characteristics that should be considered for BIAs and strong conflict of interest. This is an issue since BIAs can be of fundamental importance in managing the entry of new medicines including reimbursement decisions
Cross-platform comparability of microarray technology: Intra-platform consistency and appropriate data analysis procedures are essential
BACKGROUND: The acceptance of microarray technology in regulatory decision-making is being challenged by the existence of various platforms and data analysis methods. A recent report (E. Marshall, Science, 306, 630â631, 2004), by extensively citing the study of Tan et al. (Nucleic Acids Res., 31, 5676â5684, 2003), portrays a disturbingly negative picture of the cross-platform comparability, and, hence, the reliability of microarray technology. RESULTS: We reanalyzed Tan's dataset and found that the intra-platform consistency was low, indicating a problem in experimental procedures from which the dataset was generated. Furthermore, by using three gene selection methods (i.e., p-value ranking, fold-change ranking, and Significance Analysis of Microarrays (SAM)) on the same dataset we found that p-value ranking (the method emphasized by Tan et al.) results in much lower cross-platform concordance compared to fold-change ranking or SAM. Therefore, the low cross-platform concordance reported in Tan's study appears to be mainly due to a combination of low intra-platform consistency and a poor choice of data analysis procedures, instead of inherent technical differences among different platforms, as suggested by Tan et al. and Marshall. CONCLUSION: Our results illustrate the importance of establishing calibrated RNA samples and reference datasets to objectively assess the performance of different microarray platforms and the proficiency of individual laboratories as well as the merits of various data analysis procedures. Thus, we are progressively coordinating the MAQC project, a community-wide effort for microarray quality control
Statistical criteria for evaluating chemicals as positive or negative in the hepatocyte/DNA repair assay
The effect of time after treatment, treatment schedule and animal age on the frequency of 6-thioguanine-resistant T-lymphocytes induced in Fischer 344 rats by N-ethyl-N-nitrosourea
The persistence of 6-thioguanine-resistant (TGr) T-lymphocytes was investigated in Fischer 344 rats treated with N-ethyl-N-nitrosourea (ENU) using two schedules. Male rats, aged 3 months, were given i.p. injections containing a total of 0, 50 or 100 mg ENU/kg either as a single treatment (single-dose group) or divided among 10 weekly treatments (split-dose group). At 1, 3, 5, 10, 20, 30 and 50 weeks after the single-dose treatment, and 10, 20, 30 and 50 weeks after beginning the split-dose regimen, animals were assayed for the frequency of TGr spleen lymphocytes. ENU produced significant dose- and time-dependent responses in the single- and the split-dose treatment groups. Although a few of the 50 mg/kg split-dose treatments were significantly higher than the comparative single-dose groups, the number of TGr lymphocytes produced by the two dosing regimens were generally similar. The frequency of TGr cells for control animals increased with the age of the animals. The mode of ENU administration did not greatly influence the percent cloning efficiency (%CE) of the non-selection cultures, although the %CE declined in animals over 10 months of age. To investigate the relationship between the frequency of TGr cells and the age of the animals at the time of ENU administration, additional rats aged 17 months were treated with a single dose of ENU and at 1, 5 and 10 weeks following exposure, the frequencies of TGr cells were determined from the isolated lymphocytes. No difference in mutagen sensitivity between rats treated at 3 months of age and those treated at 17 months of age was detected at the time points evaluated. The data demonstrate the persistence of ENU-induced TGr T-lymphocytes in the rat and suggest that the dose and possibly the treatment schedule, but not the age of the animal at the time of treatment, affect the response. © 1993