Blended Survival Curves: A New Approach to Extrapolation for Time-to-Event Outcomes from Clinical Trials in Health Technology Assessment.

BACKGROUND: Survival extrapolation is essential in cost-effectiveness analysis to quantify the lifetime survival benefit associated with a new intervention, due to the restricted duration of randomized controlled trials (RCTs). Current approaches of extrapolation often assume that the treatment effect observed in the trial can continue indefinitely, which is unrealistic and may have a huge impact on decisions for resource allocation. OBJECTIVE: We introduce a novel methodology as a possible solution to alleviate the problem of survival extrapolation with heavily censored data from clinical trials. METHOD: The main idea is to mix a flexible model (e.g., Cox semiparametric) to fit as well as possible the observed data and a parametric model encoding assumptions on the expected behavior of underlying long-term survival. The two are "blended" into a single survival curve that is identical with the Cox model over the range of observed times and gradually approaching the parametric model over the extrapolation period based on a weight function. The weight function regulates the way two survival curves are blended, determining how the internal and external sources contribute to the estimated survival over time. RESULTS: A 4-y follow-up RCT of rituximab in combination with fludarabine and cyclophosphamide versus fludarabine and cyclophosphamide alone for the first-line treatment of chronic lymphocytic leukemia is used to illustrate the method. CONCLUSION: Long-term extrapolation from immature trial data may lead to significantly different estimates with various modelling assumptions. The blending approach provides sufficient flexibility, allowing a wide range of plausible scenarios to be considered as well as the inclusion of external information, based, for example, on hard data or expert opinion. Both internal and external validity can be carefully examined. HIGHLIGHTS: Interim analyses of trials with limited follow-up are often subject to high degrees of administrative censoring, which may result in implausible long-term extrapolations using standard approaches.In this article, we present an innovative methodology based on "blending" survival curves to relax the traditional proportional hazard assumption and simultaneously incorporate external information to guide the extrapolation.The blended method provides a simple and powerful framework to allow a careful consideration of a wide range of plausible scenarios, accounting for model fit to the short-term data as well as the plausibility of long-term extrapolations.

Extensions of Health Economic Evaluations in R for Microsoft Excel Users: A Tutorial for Incorporating Heterogeneity and Conducting Value of Information Analyses.

Advanced health economic analysis techniques currently performed in Microsoft Excel, such as incorporating heterogeneity, time-dependent transitions and a value of information analysis, can be easily transferred to R. Often the outputs of survival analyses (such as Weibull regression models) will estimate the impacts of correlated patient characteristics on patient outcomes, and are utilised directly as inputs for health economic decision models. This tutorial provides a step-by-step guide of how to conduct such analyses with a Markov model developed in R, and offers a comparison with established analyses performed in Microsoft Excel. This is done through the conversion of a previously published Microsoft Excel case study of a hip replacement surgery cost-effectiveness model. We hope that this paper can act as a facilitator in switching decision models from Microsoft Excel to R for complex health economic analyses, providing open-access code and data, suitable for future adaptation.

Global return on investment and cost-effectiveness of WHO's HEAR interventions for hearing loss: a modelling study.

BACKGROUND: To address the growing prevalence of hearing loss, WHO has identified a compendium of key evidence-based ear and hearing care interventions to be included within countries' universal health coverage packages. To assess the cost-effectiveness of these interventions and their budgetary effect for countries, we aimed to analyse the investment required to scale up services from baseline to recommended levels, and the return to society for every US$1 invested in the compendium. METHODS: We did a modelling study using the proposed set of WHO interventions (summarised under the acronym HEAR: hearing screening and intervention for newborn babies and infants, pre-school and school-age children, older adults, and adults at higher risk of hearing loss; ear disease prevention and management; access to technologies such as hearing aids, cochlear implants, or hearing assistive technologies; and rehabilitation service provision), which span the life course and include screening and management of hearing loss and related ear diseases, costs and benefits for the national population cohorts of 172 countries. The return on investment was analysed for the period between 2020 and 2030 using three scenarios: a business-as-usual scenario, a progress scenario with a scale-up to 50% of recommended coverage, and an ambitious scenario with scale-up to 90% of recommended coverage. Using data for hearing loss burden from the Global Burden of Disease Study 2019, a transition model with three states (general population, diagnosed, and those who have died) was developed to model the national populations in countries. For the return-on-investment analysis, the monetary value of disability-adjusted life-years (DALYs) averted in addition to productivity gains were compared against the investment required in each scenario. FINDINGS: Scaling up ear and hearing care interventions to 90% requires an overall global investment of US$238·8 billion over 10 years. Over a 10-year period, this investment promises substantial health gains with more than 130 million DALYs averted. These gains translate to a monetary value of more than US$1·3 trillion. In addition, investment in hearing care will result in productivity benefits of more than US$2 trillion at the global level by 2030. Together, these benefits correspond to a return of nearly US$15 for every US$1 invested. INTERPRETATION: This is the first-ever global investment case for integrating ear and hearing care interventions in countries' universal health coverage services. The findings show the economic benefits of investing in this compendium and provide the basis for facilitating the increase of country's health budget for strengthening ear and hearing care services. FUNDING: None.

The association of age with acute toxicities in NRG oncology combined modality lower GI cancer trials.

PURPOSE: Expected toxicity from chemoradiation (CRT) is an important factor in treatment decisions but is poorly understood in older adults with lower gastrointestinal (GI) malignancies. Our objective was to compare acute adverse events (AAEs) of older and younger adults with lower GI malignancies treated on NRG studies. METHODS: Data from 6 NRG trials, testing combined modality therapy in patients with anal or rectal cancer, were used to test the hypothesis that older age was associated with increased AAEs. AAEs and compliance with protocol-directed therapy were compared between patients aged ≥70 and < 70. Categorical variables were compared across age groups using the chi-square test. The association of age on AAEs was evaluated using a covariate-adjusted logistic regression model, with odds ratio (OR) reported. To adjust for multiple comparisons, a p-value <0.01 was considered statistically significant. RESULTS: There were 2525 patients, including 380 patients ≥70 years old (15%) evaluable. Older patients were more likely to have worse baseline performance status (PS 1 or 2) (23% vs. 16%, p = 0.001), but otherwise baseline characteristics were similar. Older patients were less likely to complete their chemotherapy (78% vs. 87%, p < 0.001), but had similar RT duration. On univariate analysis, older patients were more likely to experience grade ≥ 3 GI AAEs (36% vs. 23%, p < 0.001), and less likely to experience grade ≥ 3 skin AAEs (8% vs. 14%, p = 0.002). On multivariable analysis, older age was associated with grade ≥ 3 GI AAE (OR 1.93, 95% CI: 1.52, 2.47, p < 0.001) after adjusting for sex, race, PS, and disease site. CONCLUSIONS: Older patients with lower GI cancers who underwent CRT were less likely to complete chemotherapy and had higher rates of grade 3+ GI AAEs. These results can be used to counsel older adults prior to treatment and manage expected toxicities throughout pelvic CRT.

Assessing local chlamydia screening performance by combining survey and administrative data to account for differences in local population characteristics.

Reducing health inequalities requires improved understanding of the causes of variation. Local-level variation reflects differences in local population characteristics and health system performance. Identifying low- and high-performing localities allows investigation into these differences. We used Multilevel Regression with Post-stratification (MRP) to synthesise data from multiple sources, using chlamydia testing as our example. We used national probability survey data to identify individual-level characteristics associated with chlamydia testing and combined this with local-level census data to calculate expected levels of testing in each local authority (LA) in England, allowing us to identify LAs where observed chlamydia testing rates were lower or higher than expected, given population characteristics. Taking account of multiple covariates, including age, sex, ethnicity, student and cohabiting status, 5.4% and 3.5% of LAs had testing rates higher than expected for 95% and 99% posterior credible intervals, respectively; 60.9% and 50.8% had rates lower than expected. Residual differences between observed and MRP expected values were smallest for LAs with large proportions of non-white ethnic populations. London boroughs that were markedly different from expected MRP values (≥90% posterior exceedance probability) had actively targeted risk groups. This type of synthesis allows more refined inferences to be made at small-area levels than previously feasible.

Our experience as a Health Volunteers Overseas-sponsored team in Huê´, Vietnam.

A group from Texas Oncology and Baylor Charles A. Sammons Cancer Center traveled to Huê´, Vietnam, as part of Health Volunteers Overseas. From February 21 to March 6, 2012, five Baylor Sammons medical oncologists and an oncology nurse worked with a medical oncologist and a surgeon at the Huê´ College of Medicine and Pharmacy, suggesting approaches based on available resources. The two groups worked together to find optimal solutions for the patients. What stood out the most for the Baylor Sammons group was the Huê´ team's remarkable work ethic, empathy for patients, and treatment resourcefulness. The Baylor Sammons group also identified several unmet needs that could potentially be addressed by future volunteers in Huê´, including creation of an outpatient hospice program, establishment of breast cancer screening, modernization of the pathology department, instruction in and better utilization of pain management, better use of clinic space, and the teaching of oncology and English to medical students. There was a mutual exchange of knowledge between the two medical teams. The Baylor Sammons group not only taught but also learned how to take good care of patients with limited resources.

The relationship between numbness, tingling, and shooting/burning pain in patients with chemotherapy-induced peripheral neuropathy (CIPN) as measured by the EORTC QLQ-CIPN20 instrument, N06CA.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is characterized by numbness, tingling, and shooting/burning pain. This analysis was performed to describe the relationship between numbness, tingling, and shooting/burning pain in patients with CIPN, as reported using the EORTC QLQ-CIPN20 (CIPN20). METHODS: Baseline CIPN20 data were provided for all patients on a prospective trial designed to treat patients with bothersome CIPN. Baseline frequencies for the items on the CIPN20 are primarily described by descriptive statistics and histograms, with correlational analyses between individual items. RESULTS: A majority of the 199 patients accrued to this study reported "quite a bit" to "very much" numbness (57%) or tingling (63%) in the hands compared to "a little" or "not at all" (numbness (43%), tingling (38%)). Fewer patients reported "quite a bit" to "very much" shooting/burning pain in the hands (18%). Numbness and tingling in the hands were highly correlated (r = 0.69), while neither were highly correlated with shooting/burning pain. Similar results were observed in the feet. More severe ratings for tingling and shooting/burning pain were ascribed to the lower extremities, as opposed to the upper extremities. CONCLUSIONS: In patients with CIPN, severe sensory neuropathy symptoms (numbness, tingling) commonly exist without severe neuropathic pain symptoms (shooting/burning pain), while the reverse is not common. Symptoms in the feet should be evaluated distinctly from those in the hands as the experience of symptoms is not identical, for individual patients, in upper versus lower extremities.

A double-blind, placebo-controlled trial of a topical treatment for chemotherapy-induced peripheral neuropathy: NCCTG trial N06CA.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a troublesome chronic symptom that has no proven pharmacologic treatment. The purpose of this double-blind randomized placebo-controlled trial was to evaluate a novel compounded topical gel for this problem. METHODS: Patients with CIPN were randomized to baclofen 10 mg, amitriptyline HCL 40 mg, and ketamine 20 mg in a pluronic lecithin organogel (BAK-PLO) versus placebo (PLO) to determine its effect on numbness, tingling, pain, and function. The primary endpoint was the baseline-adjusted sensory subscale of the EORTC QLQ-CIPN20, at 4 weeks. RESULTS: Data in 208 patients reveal a trend for improvement that is greater in the BAK-PLO arm over placebo in both the sensory (p = 0.053) and motor subscales (p = 0.021). The greatest improvements were related to the symptoms of tingling, cramping, and shooting/burning pain in the hands as well as difficulty in holding a pen. There were no undesirable toxicities associated with the BAK-PLO and no evidence of systemic toxicity. CONCLUSION: Topical treatment with BAK-PLO appears to somewhat improve symptoms of CIPN. This topical gel was well tolerated, without evident systemic toxicity. Further research is needed with increased doses to better clarify the clinical role of this treatment in CIPN.