216 research outputs found

    Use of re-randomized data in meta-analysis

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    BACKGROUND: Outcomes collected in randomized clinical trials are observations of random variables that should be independent and identically distributed. However, in some trials, the patients are randomized more than once thus violating both of these assumptions. The probability of an event is not always the same when a patient is re-randomized; there is probably a non-zero covariance coming from observations on the same patient. This is of particular importance to the meta-analysts. METHODS: We developed a method to estimate the relative error in the risk differences with and without re-randomization of the patients. The relative error can be estimated by an expression depending on the percentage of the patients who were re-randomized, multipliers (how many times more likely it is to repeat an event) for the probability of reoccurrences, and the ratio of the total events reported and the initial number of patients entering the trial. RESULTS: We illustrate our methods using two randomized trials testing growth factors in febrile neutropenia. We showed that under some circumstances the relative error of taking into account re-randomized patients was sufficiently small to allow using the results in the meta-analysis. Our findings indicate that if the study in question is of similar size to other studies included in the meta-analysis, the error introduced by re-randomization will only minimally affect meta-analytic summary point estimate. We also show that in our model the risk ratio remains constant during the re-randomization, and therefore, if a meta-analyst is concerned about the effect of re-randomization on the meta-analysis, one way to sidestep the issue and still obtain reliable results is to use risk ratio as the measure of interest. CONCLUSION: Our method should be helpful in the understanding of the results of clinical trials and particularly helpful to the meta-analysts to assess if re-randomized patient data can be used in their analyses

    The risk of febrile neutropenia in patients with non-small-cell lung cancer treated with docetaxel: a systematic review and meta-analysis

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    We aimed to assess the incidence of febrile neutropenia in patients with non small cell lung cancer treated with docetaxel as second line chemotherapy by systematic review and meta-analysis of clinical studies. Published studies were retrieved and included if they considered docetaxel at the licensed dose after a previous chemotherapy regimen, and reported the proportion of patients getting FN. Meta-analysis was conducted to estimate the proportion of patients who experience one or more episodes of FN. The pooled, random effects meta-analysis estimate for the proportion of patients who experience one or more episodes of FN on docetaxel was 5.95% (95% CI 4.22–8.31) based on 13 studies, comprising 1609 patients. No significant differences were seen either between studies that permitted the use of prophylactic granulocyte colony-stimulating factors or between phase II and phase III trials

    Management of febrile neutropenia in the United Kingdom: time for a national trial?

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    Recent advances in febrile neutropenia (FN) have highlighted the value of risk stratification and the evolving role of oral antibiotics with early hospital discharge in low-risk patients. The aim of this study was to survey whether these advances have been translated into routine clinical practice in the UK. Questionnaires were sent to cancer clinicians across the UK to determine clinicians' routine management of FN, including use of risk stratification, antibiotic regimen and criteria for hospital discharge. In all, 128 clinicians responded, representing 50 cancer departments (83%). Only 38% of respondents stratify patients according to risk and with substantial variation in the criteria defining ‘low-risk'. Furthermore, only 22% of clinicians use oral antibiotics as first-line treatment in any patients with FN, but this was significantly greater among clinicians who do compared to those who do not stratify patients by risk, 51 vs 4% (P<0.0001). These findings suggest a slow and/or cautious introduction of newer strategies for the management of low-risk FN in the UK. However, 84% of respondents confirmed their willingness to participate in a trial of oral antibiotics combined with early discharge in low-risk FN

    Experiencing neutropenia: Quality of life interviews with adult cancer patients

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    BACKGROUND: Neutropenia is a common toxicity in chemotherapy but detailed information about how neutropenia is associated with changes in patients' quality of life is not readily available. This prospective study interviewed patients with grade 4 neutropenia to provide qualitative information on patients' experience of developing and coping with grade 4 neutropenia during a cycle of chemotherapy. METHODS: A sample of 34 patients who developed grade 4 neutropenia during the first cycle of chemotherapy completed a total of 100 structured clinical interviews. Interviews were transcribed, and 2 raters inductively developed 5 broad categories comprising 80 specific complaint domains nominated by patients. Thirty-five patient-nominated problems were mentioned in 5% or more of the interviews. RESULTS: Fatigue was the most common physical symptom. Interference in daily routine, negative self-evaluation, negative emotion, and social isolation were other common complaints associated with neutropenia. CONCLUSION: Neutropenia is associated with a number of negative experiences among cancer patients undergoing chemotherapy, and these negative experiences have an adverse effect on the patient's quality of life. Oncology nurses can play a key role in helping patients manage adverse effects to maintain their quality of life

    Modulation of macrophage cytokine profiles during solid tumor progression: susceptibility to Candida albicans infection

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    <p>Abstract</p> <p>Background</p> <p>In order to attain a better understanding of the interactions between opportunist fungi and their hosts, we investigated the cytokine profile associated with the inflammatory response to <it>Candida albicans </it>infection in mice with solid Ehrlich tumors of different degrees.</p> <p>Methods</p> <p>Groups of eight animals were inoculated intraperitoneally with 5 × 10<sup>6 </sup><it>C. albicans </it>7, 14 or 21 days after tumor implantation. After 24 or 72 hours, the animals were euthanized and intraperitoneal lavage fluid was collected. Peritoneal macrophages were cultivated and the levels of IFN-γ, TNF-α, IL-12, IL-10 and IL-4 released into the supernatants were measured by ELISA. Kidney, liver and spleen samples were evaluated for fungal dissemination. Tumor-free animals and animals that had only been subjected to <it>C. albicans </it>infection were used as control groups.</p> <p>Results</p> <p>Our results demonstrated that the mice produced more IFN-γ and TNF-α and less IL-10, and also exhibited fungal clearance, at the beginning of tumor evolution. With the tumor progression, this picture changed: IL-10 production increased and IFN-γ and TNF-α release decreased; furthermore, there was extensive fungal dissemination.</p> <p>Conclusion</p> <p>Our results indicate that solid tumors can affect the production of macrophage cytokines and, in consequence, affect host resistance to opportunistic infections.</p

    Does HAART Efficacy Translate to Effectiveness? Evidence for a Trial Effect

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    Background: Patients who participate in clinical trials may experience better clinical outcomes than patients who initiate similar therapy within clinical care (trial effect), but no published studies have evaluated a trial effect in HIV clinical trials. Methods: To examine a trial effect we compared virologic suppression (VS) among patients who initiated HAART in a clinical trial versus in routine clinical care. VS was defined as a plasma HIV RNA #400 copies/ml at six months after HAART initiation and was assessed within strata of early (1996–99) or current (2000–06) HAART periods. Risk ratios (RR) were estimated using binomial models. Results: Of 738 persons initiating HAART, 30.6 % were women, 61.7 % were black, 30 % initiated therapy in a clinical trial and 67 % (n = 496) had an evaluable six month HIV RNA result. HAART regimens differed between the early and current periods (p,0.001); unboosted PI regimens (55.6%) were more common in the early and NNRTI regimens (46.4%) were more common in the current period. Overall, 78 % (95%CI 74, 82%) of patients achieved VS and trial participants were 16 % more likely to achieve VS (unadjusted RR 1.16, 95%CI 1.06, 1.27). Comparing trial to non-trial participants, VS differed by study period. In the early period, trial participants initiating HAART were significantly more likely to achieve VS than non-trial participants (adjusted RR 1.33; 95%CI 1.15, 1.54), but not in the current period (adjusted RR 0.98; 95%CI 0.87, 1.11). Conclusions: A clear clinical trial effect on suppression of HIV replication was observed in the early HAART period but not i
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