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Dive into the research topics where Sophie Whyte is active.

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Featured researches published by Sophie Whyte.


BMC Cancer | 2011

Granulocyte colony-stimulating factors for febrile neutropenia prophylaxis following chemotherapy: systematic review and meta-analysis

Katy Cooper; Jason Madan; Sophie Whyte; Matt Stevenson; Ron Akehurst

BackgroundFebrile neutropenia (FN) occurs following myelosuppressive chemotherapy and is associated with morbidity, mortality, costs, and chemotherapy reductions and delays. Granulocyte colony-stimulating factors (G-CSFs) stimulate neutrophil production and may reduce FN incidence when given prophylactically following chemotherapy.MethodsA systematic review and meta-analysis assessed the effectiveness of G-CSFs (pegfilgrastim, filgrastim or lenograstim) in reducing FN incidence in adults undergoing chemotherapy for solid tumours or lymphoma. G-CSFs were compared with no primary G-CSF prophylaxis and with one another. Nine databases were searched in December 2009. Meta-analysis used a random effects model due to heterogeneity.ResultsTwenty studies compared primary G-CSF prophylaxis with no primary G-CSF prophylaxis: five studies of pegfilgrastim; ten of filgrastim; and five of lenograstim. All three G-CSFs significantly reduced FN incidence, with relative risks of 0.30 (95% CI: 0.14 to 0.65) for pegfilgrastim, 0.57 (95% CI: 0.48 to 0.69) for filgrastim, and 0.62 (95% CI: 0.44 to 0.88) for lenograstim. Overall, the relative risk of FN for any primary G-CSF prophylaxis versus no primary G-CSF prophylaxis was 0.51 (95% CI: 0.41 to 0.62). In terms of comparisons between different G-CSFs, five studies compared pegfilgrastim with filgrastim. FN incidence was significantly lower for pegfilgrastim than filgrastim, with a relative risk of 0.66 (95% CI: 0.44 to 0.98).ConclusionsPrimary prophylaxis with G-CSFs significantly reduces FN incidence in adults undergoing chemotherapy for solid tumours or lymphoma. Pegfilgrastim reduces FN incidence to a significantly greater extent than filgrastim.


British Journal of Cancer | 2012

Cost-effectiveness of population-based screening for colorectal cancer: a comparison of guaiac-based faecal occult blood testing, faecal immunochemical testing and flexible sigmoidoscopy

Linda Sharp; Lesley Tilson; Sophie Whyte; Alan O'Ceilleachair; Cathal Walsh; Cara Usher; Paul Tappenden; Jim Chilcott; Anthony Staines; Michael J. Barry; Harry Comber

Background:Several colorectal cancer-screening tests are available, but it is uncertain which provides the best balance of risks and benefits within a screening programme. We evaluated cost-effectiveness of a population-based screening programme in Ireland based on (i) biennial guaiac-based faecal occult blood testing (gFOBT) at ages 55–74, with reflex faecal immunochemical testing (FIT); (ii) biennial FIT at ages 55–74; and (iii) once-only flexible sigmoidoscopy (FSIG) at age 60.Methods:A state-transition model was used to estimate costs and outcomes for each screening scenario vs no screening. A third party payer perspective was adopted. Probabilistic sensitivity analyses were undertaken.Results:All scenarios would be considered highly cost-effective compared with no screening. The lowest incremental cost-effectiveness ratio (ICER vs no screening [euro ]589 per quality-adjusted life-year (QALY) gained) was found for FSIG, followed by FIT ([euro ]1696) and gFOBT ([euro ]4428); gFOBT was dominated. Compared with FSIG, FIT was associated with greater gains in QALYs and reductions in lifetime cancer incidence and mortality, but was more costly, required considerably more colonoscopies and resulted in more complications. Results were robust to variations in parameter estimates.Conclusion:Population-based screening based on FIT is expected to result in greater health gains than a policy of gFOBT (with reflex FIT) or once-only FSIG, but would require significantly more colonoscopy resources and result in more individuals experiencing adverse effects. Weighing these advantages and disadvantages presents a considerable challenge to policy makers.


PharmacoEconomics | 2012

Bevacizumab for Metastatic Colorectal Cancer: A NICE Single Technology Appraisal.

Sophie Whyte; Abdullah Pandor; Matt Stevenson

The National Institute for Health and Clinical Excellence (NICE) invited the manufacturer of bevacizumab (Roche Products) to submit evidence for the clinical and cost effectiveness of this drug for the treatment of patients with metastatic colorectal cancer (mCRC), as part of the Institute’s Single Technology Appraisal (STA) process. The School of Health and Related Research (ScHARR) at the University of Sheffield was commissioned to act as the Evidence Review Group (ERG). This paper provides a description of the company submission, the ERG review and NICE’s subsequent decisions.The ERG produced a critical review of the evidence for the clinical and cost effectiveness of the technology provided within the manufacturer’s submission to NICE. The ERG also independently searched for relevant evidence and modified the manufacturer’s decision analytic model to examine the impact of altering some of the key assumptions.The main clinical effectiveness data were derived from a phase III, multicentre, multinational, two-arm, randomized, open-label study with the primary objective of confirming the non-inferiority of oxaliplatin plus capecitabine (XELOX) compared with oxaliplatin plus 5-fluorouracil and folinic acid (FOLFOX-4) in adult patients with histologically confirmed mCRC who had not previously been treated. The ERG considered that the NO 16966 trial was of reasonable methodological quality and demonstrated a significant improvement in both progression-free and overall survival when bevacizumab is added to either XELOX or FOLFOX-4. The ERG considered that the size of the actual treatment effect of bevacizumab was uncertain due to trial design limitations, imbalance of a known prognostic factor, relatively short treatment duration compared with that allowed within the trial protocol, and interpretation of the statistical analyses.The manufacturer’s submission included a de novo economic evaluation using a cost-effectiveness model built in Microsoft® Excel. The ERG believed that the modelling structure employed was appropriate but highlighted several areas of uncertainty that had the potential to have a significant impact on the resulting incremental cost-effectiveness ratios (ICERs). The areas of uncertainty identified by the ERG included whether chemotherapy would be administered continuously or intermittently, patient access scheme (PAS) costs and uptake, survival that was dependent on the statistical analyses used, and the likely duration of continued treatment with bevacizumab after cessation of oxaliplatin and the efficacy associated with continuation.The STA described here highlighted the challenges in appraising interventions with a complex PAS. Based on the analyses that include a discount to the list price of oxaliplatin, the ERG concluded that the ICERs for the addition of bevacizumab to XELOX or FOLFOX were both over £50 000. The NICE Appraisal Committee concluded that bevacizumab in combination with oxaliplatin and either 5-fluorouracil plus folinic acid or capecitabine (i.e. FOLFOX or XELOX) was not recommended for the treatment of mCRC.


Medical Decision Making | 2011

Bayesian Calibration of a Natural History Model with Application to a Population Model for Colorectal Cancer

Sophie Whyte; Cathal Walsh; Jim Chilcott

Background. Cancer natural history models are essential when evaluating screening/preventative interventions or changes to diagnostic pathways. Natural history models commonly use a state transition structure, but it is often not possible to observe the state transition probabilities required for parameterization. Aim. The work aimed to accurately represent the uncertainty in the parameters of a state transition model for the natural history of colorectal cancer by embedding the problem in the framework of Bayesian inference. Methods. The Metropolis-Hastings algorithm was used to estimate natural history parameters and screening test characteristics by generating multiple sets of parameters from the posterior distribution, which is the probability distribution that is compatible with the observed data. Observed data included colorectal cancer incidence categorized by age and stage, autopsy data on polyp prevalence, and cancer and polyp detection rates from the first round of screening with the fecal occult blood test in England. The approach was implemented using Visual Basic. Results. The results were subsequently examined for convergence using the package CODA in R 2.8.0. Outputs from fitting were samples from the joint posterior distribution of the natural history parameters given the epidemiological data. The parameter sets obtained are shown to have a good fit to all the observed data sets. These parameter sets are used when running probabilistic sensitivity analysis. Conclusion. The advantages of this strategy are that it draws efficiently from a high-dimensional correlated parameter space. The algorithm is simple to code and runs overnight on a standard desktop PC. Using this method, the parameter sets are drawn according to their posterior probability given calibration data, and thus they correctly summarize the residual uncertainty in the parameter space.


European Journal of Health Economics | 2012

Cost of care for colorectal cancer in Ireland: a health care payer perspective

Lesley Tilson; Linda Sharp; Cara Usher; Cathal Walsh; Sophie Whyte; Alan Ó Céilleachair; Charlotte Stuart; Brian Mehigan; M. John Kennedy; Paul Tappenden; Jim Chilcott; Anthony Staines; Harry Comber; Michael J. Barry

ObjectiveManagement options for colorectal cancer have expanded in recent years. We estimated average lifetime cost of care for colorectal cancer in Ireland in 2008, from the health care payer perspective.MethodA decision tree model was developed in Microsoft EXCEL. Site and stage-specific treatment pathways were constructed from guidelines and validated by expert clinical opinion. Health care resource use associated with diagnosis, treatment and follow-up were obtained from the National Cancer Registry Ireland (n=1,498 cancers diagnosed during 2004–2005) and three local hospital databases (n=155, 142 and 46 cases diagnosed in 2007). Unit costs for hospitalisation, procedures, laboratory tests and radiotherapy were derived from DRG costs, hospital finance departments, clinical opinion and literature review. Chemotherapy costs were estimated from local hospital protocols, pharmacy departments and clinical opinion. Uncertainty was explored using one-way and probabilistic sensitivity analysis.ResultsIn 2008, the average (stage weighted) lifetime cost of managing a case of colorectal cancer was €39,607. Average costs were 16% higher for rectal (€43,502) than colon cancer (€37,417). Stage I disease was the least costly (€23,688) and stage III most costly (€48,835). Diagnostic work-up and follow-up investigations accounted for 4 and 5% of total costs, respectively. Cost estimates were most sensitive to recurrence rates and prescribing of biological agents.ConclusionThis study demonstrates the value of using existing data from national and local databases in contributing to estimating the cost of managing cancer. The findings illustrate the impact of biological agents on costs of cancer care and the potential of strategies promoting earlier diagnosis to reduce health care resource utilisation and care costs.


Colorectal Disease | 2012

Reappraisal of the options for colorectal cancer screening in England

Sophie Whyte; Jim Chilcott; Stephen P. Halloran

Aim  The aim was to use newly available data to estimate the cost effectiveness and endoscopy requirements of screening options for colorectal cancer (CRC) to inform screening policy in England.


Medical Decision Making | 2016

Eliciting Societal Preferences for Weighting QALYs for Burden of Illness and End of Life

Donna Rowen; John Brazier; Clara Mukuria; Anju Devianee Keetharuth; Arne Risa Hole; Aki Tsuchiya; Sophie Whyte; Phil Shackley

Objectives . Recent proposals for value-based assessment, made by the National Institute of Health and Care Excellence (NICE) in the United Kingdom, recommended that burden of illness (BOI) should replace end of life (EOL) as a factor for consideration when deciding on new health technologies. This article reports on a study eliciting societal preferences for 1) BOI from a medical condition, defined as quality-adjusted life year (QALY) loss due to premature mortality and prospective morbidity, and 2) EOL, defined as expected life expectancy of less than 2 years and expected life expectancy gain from new treatment of 3 months or more. Methods . A discrete choice experiment survey was conducted with an online UK general population sample. Respondents chose whether they thought the health service should treat patient group A or B: life expectancy and health-related quality of life (HRQOL) with current treatment or life expectancy and HRQOL gains from new treatment, respectively. These attributes were used to derive BOI, QALY gain, and EOL. The respondents’ choices were analyzed using conditional logistic regression with a range of specifications examined, including BOI or EOL, QALY gain and QALY gain squared, and robustness. QALY weights were estimated. Results . The sample of 3669 respondents was representative of the UK population for age and sex. QALY gain had a positive and significant coefficient across all models. QALY gain squared term was negative and significant across all models, indicating a diminishing marginal social value from QALY gains. When included, the BOI coefficient was generally small, positive, and significant, but this was not consistent across the different life expectancy variants. EOL was always positive and significant. Conclusions . The social value of a QALY gain is not equal between recipients but depends on whether they are end of life, and it may depend on the prospective burden of illness.


Health Technology Assessment | 2010

Bevacizumab in combination with fluoropyrimidine-based chemotherapy for the first-line treatment of metastatic colorectal cancer

Sophie Whyte; Abdullah Pandor; Matt Stevenson; A Rees

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of bevacizumab in combination with fluoropyrimidine-based chemotherapy for the first-line treatment of metastatic colorectal cancer based on the manufacturers submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. Evidence was available in the form of one phase III, multicentre, multinational, randomised, open-label study (NO16966 trial). This two-arm study was originally designed to demonstrate the non-inferiority of oral capecitabine plus oxaliplatin (XELOX) compared with 5-fluorouracil plus folinic acid plus oxaliplatin (FOLFOX)-4 in adult patients with histologically confirmed metastatic colorectal cancer who had not previously been treated. Following randomisation of 634 patients, the open-label study was amended to include a 2 × 2 factorial randomised (partially blinded for bevacizumab) phase III trial with the coprimary objective of demonstrating superiority of bevacizumab in combination with chemotherapy compared with chemotherapy alone. Measured outcomes included overall survival, progression-free survival, response rate, adverse effects of treatment and health-related quality of life. The manufacturers primary pooled analysis of superiority (using the intention-to-treat population) showed that after a median follow-up of 28 months, the addition of bevacizumab to chemotherapy significantly improved progression-free survival and overall survival compared with chemotherapy alone in adult patients with histologically confirmed metastatic colorectal cancer who were not previously treated [median progression-free survival 9.4 vs 7.7 months (absolute difference 1.7 months); hazard ratio (HR) 0.79, 97.5% confidence interval (CI) 0.72 to 0.87; p = 0.0001; median overall survival 21.2 vs 18.9 months (absolute difference 2.3 months); HR 0.83, 97.5% CI 0.74 to 0.93; p = 0.0019]. The NO16966 trial was of reasonable methodological quality and demonstrated a significant improvement in both progression-free survival and overall survival when bevacizumab was added to XELOX or FOLFOX. However, the size of the actual treatment effect of bevacizumab is uncertain. The ERG believed that the modelling structure employed was appropriate, but highlighted several key issues and areas of uncertainty. At the time of writing, NICE was yet to issue the guidance for this appraisal.


BMC Health Services Research | 2013

Using resource modelling to inform decision making and service planning: the case of colorectal cancer screening in Ireland

Linda Sharp; Lesley Tilson; Sophie Whyte; Alan Ó Céilleachair; Cathal Walsh; Cara Usher; Paul Tappenden; Jim Chilcott; Anthony Staines; Michael J. Barry; Harry Comber

BackgroundOrganised colorectal cancer screening is likely to be cost-effective, but cost-effectiveness results alone may not help policy makers to make decisions about programme feasibility or service providers to plan programme delivery. For these purposes, estimates of the impact on the health services of actually introducing screening in the target population would be helpful. However, these types of analyses are rarely reported. As an illustration of such an approach, we estimated annual health service resource requirements and health outcomes over the first decade of a population-based colorectal cancer screening programme in Ireland.MethodsA Markov state-transition model of colorectal neoplasia natural history was used. Three core screening scenarios were considered: (a) flexible sigmoidoscopy (FSIG) once at age 60, (b) biennial guaiac-based faecal occult blood tests (gFOBT) at 55–74 years, and (c) biennial faecal immunochemical tests (FIT) at 55–74 years. Three alternative FIT roll-out scenarios were also investigated relating to age-restricted screening (55–64 years) and staggered age-based roll-out across the 55–74 age group. Parameter estimates were derived from literature review, existing screening programmes, and expert opinion. Results were expressed in relation to the 2008 population (4.4 million people, of whom 700,800 were aged 55–74).ResultsFIT-based screening would deliver the greatest health benefits, averting 164 colorectal cancer cases and 272 deaths in year 10 of the programme. Capacity would be required for 11,095-14,820 diagnostic and surveillance colonoscopies annually, compared to 381–1,053 with FSIG-based, and 967–1,300 with gFOBT-based, screening. With FIT, in year 10, these colonoscopies would result in 62 hospital admissions for abdominal bleeding, 27 bowel perforations and one death. Resource requirements for pathology, diagnostic radiology, radiotherapy and colorectal resection were highest for FIT. Estimates depended on screening uptake. Alternative FIT roll-out scenarios had lower resource requirements.ConclusionsWhile FIT-based screening would quite quickly generate attractive health outcomes, it has heavy resource requirements. These could impact on the feasibility of a programme based on this screening modality. Staggered age-based roll-out would allow time to increase endoscopy capacity to meet programme requirements. Resource modelling of this type complements conventional cost-effectiveness analyses and can help inform policy making and service planning.


Tumori | 2009

Comprehensive cancer control-research & development: knowing what we do and doing what we know

Jon Kerner; Eduardo Cazap; Derek Yach; Marco A. Pierotti; Maria Grazia Daidone; Pasquale De Blasio; Peter Geary; Brent Schacter; Milena Sant; J. Dik F. Habbema; Rengaswamy Sankaranarayanan; Catherine G. Sutcliffe; Simon Sutcliffe; J. K. Kaijage; P. A. Scanlan; S. Gibson; A. M. Mes-Masson; M. Sawyer; L. Shepherd; P. Watson; B. Zanke; I. A. Small; D. B. Olmedo; M. D. Breitenbach; L. A. Santini; L. A. Maltoni; D. Ramalho; C. G. Ferreira; Linda Sharp; S. Cotton

Comprehensive cancer control is defined as an integrated and coordinated approach to reducing cancer incidence, morbidity, and mortality across the cancer control continuum from primary prevention to end-of-life care. This approach assumes that when the public sector, non-governmental organizations, academia, and the private sector share with each other their skills, knowledge, and resources, a country can take advantage of all its talents and resources to more quickly reduce the burden of cancer for all its population. One critical issue for comprehensive cancer control is the extent to which the private sector can contribute to cancer prevention and control programs and policies that have historically been lead by the public health sector, and similarly how can the public sector increase its investment and involvement in clinical research and practice issues that are largely driven by the private sector worldwide? In addition, building capacity to integrate research that is appropriate to the culture and context of the population will be important in different settings, in particular research related to cancer control interventions that have the capacity to influence outcomes. To whatever extent cancer control research is ultimately funded through the private and public sectors, if investments in research discoveries are ultimately to benefit the populations that bear the greatest burden of disease, then new approaches to integrating the lessons learned from science with the lessons learned from service (public health, clinical, and public policy) must be found to close the gap between what we know and what we do. Communities of practice for international cancer control, like the ones fostered by the first three International Cancer Control Congresses, represent an important forum for knowledge exchange opportunities to accelerate the translation of new knowledge into action to reduce the burden of cancer worldwide.

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Jim Chilcott

University of Sheffield

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Ron Akehurst

University of Sheffield

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Ruth Wong

University of Sheffield

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Keith Cooper

University of Southampton

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