Alternative Conversion Methods for Transition Probabilities in State-Transition Models: Validity and Impact on Comparative Effectiveness and Cost-Effectiveness

2019 ◽  
Vol 39 (5) ◽  
pp. 509-522 ◽  
Author(s):  
Beate Jahn ◽  
Christina Kurzthaler ◽  
Jagpreet Chhatwal ◽  
Elamin H. Elbasha ◽  
Annette Conrads-Frank ◽  
...  
Keyword(s):  
State Transition ◽  
Transition Probabilities ◽  
Treatment Strategies ◽  
Transition Matrices ◽  
Long Term Outcomes ◽  
Health States ◽  
Life Years ◽  
Transition Models ◽  
Transformation Methods

Background. In state-transition models (STMs), decision problems are conceptualized using health states and transitions among those health states after predefined time cycles. The naive, commonly applied method (C) for cycle length conversion transforms all transition probabilities separately. In STMs with more than 2 health states, this method is not accurate. Therefore, we aim to describe and compare the performance of method C with that of alternative matrix transformation methods. Design. We compare 2 alternative matrix transformation methods (Eigenvalue method [E], Schure-Padé method [SP]) to method C applied in an STM of 3 different treatment strategies for women with breast cancer. We convert the given annual transition matrix into a monthly-cycle matrix and evaluate induced transformation errors for the transition matrices and the long-term outcomes: life years, quality-adjusted life-years, costs and incremental cost-effectiveness ratios, and the performance related to the decisions. In addition, we applied these transformation methods to randomly generated annual transition matrices with 4, 7, 10, and 20 health states. Results. In theory, there is no generally applicable correct transformation method. Based on our simulations, SP resulted in the smallest transformation-induced discrepancies for generated annual transition matrices for 2 treatment strategies. E showed slightly smaller discrepancies than SP in the strategy, where one of the direct transitions between health states was excluded. For long-term outcomes, the largest discrepancy occurred for estimated costs applying method C. For higher dimensional models, E performs best. Conclusions. In our modeling examples, matrix transformations (E, SP) perform better than transforming all transition probabilities separately (C). Transition probabilities based on alternative conversion methods should therefore be applied in sensitivity analyses.

Treatment strategies and long-term outcomes for primary intramedullary spinal germinomas: an institutional experience

2014 ◽  
Vol 121 (3) ◽  
pp. 541-548 ◽  
Author(s):  
Liang Wu ◽  
Tao Yang ◽  
Xiaofeng Deng ◽  
Chenlong Yang ◽  
Jingyi Fang ◽  
...  
Keyword(s):  
Treatment Strategies ◽  
Long Term Outcomes ◽  
Institutional Experience

scholarly journals Short- and long-term outcomes of treatment strategies for isolated penetrating aortic ulcers (PAUs)

2020 ◽  
Vol 59 (5) ◽  
pp. e31
Author(s):  
Safa Salim ◽  
Rossella Locci ◽  
Guy Martin ◽  
Rick Gibbs ◽  
Michael Jenkins ◽  
...  
Keyword(s):  
Treatment Strategies ◽  
Long Term Outcomes ◽  
Short And Long Term

scholarly journals Estimating the Relative Treatment Effect and Corresponding Cost-Effectiveness Estimates of Inotuzumab Ozogamicin Vs. Blinatumomab for Adults with Philadelphia Chromosome-Negative (Ph-) Relapsed/Refractory (R/R) B-Cell Acute Lymphoblastic Leukaemia (B-ALL) in the United Kingdom (UK)

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3427-3427 ◽  
Author(s):  
Simone Critchlow ◽  
Miranda Cooper ◽  
Ilse van Oostrum ◽  
Verna L Welch ◽  
T. Alexander Russell-Smith
Keyword(s):  
Cost Effectiveness ◽  
Cost Effective ◽  
Complete Response ◽  
Health State ◽  
Health States ◽  
Term Survival ◽  
Long Term Survival ◽  
Treatment Comparison ◽  
Life Years

Introduction: Inotuzumab ozogamicin (InO), is a novel anti-CD22 antibody-calicheamicin conjugate approved in R/R B-ALL due to its high hematologic remission rate (81%) based on the phase 3 INO-VATE trial comparing to investigators choice (IC). The TOWER trial demonstrated the efficacy and safety of blinatumomab (Blina) for treatment of Ph- B-ALL versus IC. The relative effectiveness of InO versus Blina was investigated by applying indirect treatment comparison (ITC) methods. A UK-based cost-effectiveness model (CEM) submitted to the Scottish Medicines Consortium (SMC) explored the impact of treatment differences with regard to mean life years (LY) gained and quality-adjusted life years (QALY). Methods: As R/R ALL is a terminal disease if left untreated, achievement of complete response/complete response with incomplete count recovery (CR/CRi) in conjunction with stem cell transplant (SCT) is essential for long-term survival. The three most important outcomes related to treatment are thus the level of response determined by CR/CRi, the rate of SCT, and overall survival (OS). Without potentially curative therapy such as SCT, there is no evidence to suggest long-term survival is possible. Therefore, to compare InO to Blina, comparisons of these outcomes were explored using patient-level data from the INO-VATE ALL trial and aggregate data from the TOWER trial. The CEM structure contained four health states categorising patients based on 'No CR/CRi & no SCT', 'CR/CRi and no SCT' and patients receiving SCT ('SCT/Post SCT') - with progression-free survival (PFS) and OS modelled within these states. States were clinically validated as relevant to treatment of the disease. Death was the fourth health state. Different methods were incorporated to allocate Blina patients to the respective health-states. For levels of response (CR/CRi) and SCT a matching-adjusted indirect comparison (MAIC) and a Bucher ITC were explored. As CR/CRi and SCT rates are not mutually exclusive, a multinomial ITC was also conducted. Once allocated into respective health states, OS and PFS were modelled. Three ITC methods were used to compare OS; a simulated treatment comparison (STC), MAIC and a standard network meta-analysis. In the absence of PFS data for Blina, PFS was assumed to have the same relative treatment effect as OS. Quality of life data within the model for the 'No CR/CRi & no SCT' and 'CR/CRi and no SCT' were informed from InO trial data, while SCT quality of life was informed from the literature with time-varying utilities. Costs were incorporated from a UK perspective using 2017 sources and were those submitted to the SMC. Results were annually discounted at 3.5%. Results: Health state proportions for Ph- InO patients were used as the basis to estimate corresponding Blina proportions and show 49.3% of patients treated with InO reach SCT. With higher odds for CR/CRi and SCT for InO, the ITC results consistently indicate Blina leads to lower proportions of patients receiving SCT (19.1-22.5%) and CR/CRi (25.2-33.3%). ITCs comparing OS outcomes for InO versus blinatumomab show negligible differences between treatments, consistently across the three methods. All combinations of the various methods were explored using the list price for both treatments. The results of the CEM ranged from 0.91-1.14 incremental QALYs for InO versus Blina, while LYs ranged from 2.03-2.59 resulting from higher rates of SCT. The incremental cost-effectiveness ratio (ICER) ranged from £3,700 to £7,010 for InO versus Blina. Extensive scenario analysis indicates that InO is a cost-effective option compared to Blina at a willingness to pay threshold of £20,000 per QALY. The SMC recommended InO as a cost-effective use of resources citing an ICER of £6,754 in the CEM when using the MAIC; InO was associated with a mean survival gain of >29 months over Blina corresponding to this ICER. Conclusions: Outcomes from the ITC indicate that InO provides patients with a greater probability of achieving CR/CRi and/or receiving a subsequent SCT versus Blina. As CR/CRi followed by SCT are essential for long-term survival and potential cure, the mean OS gain in the model cited in the SMC recommendation is intuitive as it aligns with the superior CR/CRi and SCT odds ratios associated with InO. Further research is required to determine the long-term PFS and OS following SCT in R/R B-ALL, beyond what can be reliably captured within clinical trials. Disclosures Critchlow: BresMed Health Solutions Ltd.: Consultancy. Cooper:BresMed Health Solutions Ltd.: Consultancy. van Oostrum:Ingress Health: Employment; Pfizer: Consultancy; Merck: Consultancy; Janssen: Consultancy; AstraZeneca: Consultancy. Welch:Pfizer Inc: Employment, Equity Ownership. Russell-Smith:Pfizer: Employment, Equity Ownership.

Ebola and Other Filoviruses

2018 ◽  
Author(s):  
Lisa M. Bebell
Keyword(s):  
Ebola Virus ◽  
Inflammatory Responses ◽  
Virus Disease ◽  
Treatment Strategies ◽  
Disease Outbreaks ◽  
Marburg Virus ◽  
Residual Effects ◽  
Long Term Outcomes ◽  
Pediatric Vaccination

Congenital and pediatric Ebola virus disease (EVD) and Marburg virus disease (MVD) are severe, even lethal infections. Historically, children have been underrepresented in filovirus disease outbreaks, and evidence-based treatment strategies are lacking. Existing data suggest that case fatalities are highest among children under four years of age, which is partially explained by higher virus concentrations in young children. Prevention and aggressive resuscitation, nutrition, and supportive care are the mainstays of management until filovirus-specific therapies can be developed. Differences in pediatric immune and inflammatory responses may necessitate unique approaches to pediatric vaccination and treatment. There are minimal safety or immunogenicity data in children, a crucial knowledge gap that must be addressed in future trials. Studying pediatric survivors of the 2014–2016 West Africa EVD outbreak will provide much-needed data on long-term outcomes and residual effects of filovirus disease while we await effective filovirus-specific vaccines and therapies.

Cost-effectiveness of nodal observation versus completion lymphadenectomy in patients with melanoma and sentinel lymph node metastases.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e22076-e22076
Author(s):  
Elena Parvez ◽  
Teodora Dumitra ◽  
Dimitra Panagiotoglou ◽  
Sarkis H. Meterissian ◽  
Sinziana Dumitra
Keyword(s):  
Cost Effectiveness ◽  
Transition Probabilities ◽  
Treatment Strategies ◽  
Cost Savings ◽  
Cost Effective ◽  
Health State ◽  
Complication Rates ◽  
Disease States ◽  
Payer Perspective ◽  
Life Years

e22076 Background: The MSLT-II trial demonstrated no survival benefit of completion lymphadenectomy (CLND) compared to nodal observation (NO) and subsequent therapeutic lymphadenectomy (TLND) in the case of macroscopic nodal relapse in patients with melanoma and SLN metastases. NO avoids the upfront cost and morbidity of CLND. However, patients followed with NO must undergo intensive surveillance and if TLND is required, it is associated with a higher complication rate than CLND. The cost-effectiveness of NO versus CLND in light of data from MSLT-II has not been previously studied. Methods: A Markov model with a 10-year time horizon was constructed to simulate two hypothetical cohorts of patients with SLN metastases undergoing NO and subsequent TLND for nodal recurrence or upfront CLND. Transition probabilities between disease states were derived from the MSLT-II trial. Remaining parameters including complication rates and health state utilities were obtained from an extensive review of the literature. Direct health care system costs were obtained from published US Medicare cost data and the literature. Primary outcomes were cost and quality-adjusted life years (QALYs) saved. Incremental cost-effectiveness ratio (ICER) was used to compare treatment strategies. Sensitivity analysis was performed in order to evaluate model uncertainty. A threshold of acceptance of $100,000/QALY was used. Results: Total projected cost over the study period for CLND was $28,609.87, while that of NO was lower at $20,865.27, resulting in $7,744.60 saved for the NO treatment strategy. Ten-year utility was 4.840 for CLND compared to 5.379 for NO, resulting in a gain of 0.539 QALYs in the NO arm. The NO strategy is dominant in the model as it results in both cost-savings and a gain in health effects, with an average ICER of -$14,368.46/QALY gained. Conclusions: From the payer perspective, the strategy of NO compared to CLND in patients with melanoma and SLN metastases is associated with an improvement in health outcomes and reduction in cost. Taking into account MSLT-II trial data, this study demonstrates NO is more cost-effective than CLND.

Cervical Radiculopathy

2018 ◽  
pp. 231-236
Author(s):  
Samuel W. Samuel ◽  
Eduardo E. Icaza
Keyword(s):  
Conservative Management ◽  
Treatment Strategies ◽  
Cervical Radiculopathy ◽  
Surgical Decompression ◽  
Evidence Based ◽  
Long Term Outcomes ◽  
Painful Condition ◽  
Surgical Treatments ◽  
Cervical Root

This chapter discusses cervical radiculopathy, a common, painful condition from cervical root compression, irritation, or both. A thorough history and physical exam can often help in diagnosing the affected nerve root, without the need for reflexive imaging. A series of provocative tests can aid in the differential diagnosis. Most cases will be resolved with conservative management within several weeks of symptoms onset. Evidence-based conservative management includes physical therapy and oral NSAIDs. If symptoms indicate myelopathic changes or are refractory to 6 to 8 weeks of conservative management, advanced imaging such as MRI should be considered. Patients with imaging evidence of a compressive etiology and refractory to conservative therapy should have a surgical consultation. Either an MRI or CT should be obtained before surgical decompression. Both interventional and surgical treatments have had positive outcomes in the short term, but long-term outcomes appear comparable to those with conservative therapies. It is recommended that conservative treatment strategies be used for 6–8 weeks before pursuing procedural or surgical intervention.

Treatment of Early-Stage Breast Cancer in the Elderly

1998 ◽  
Vol 18 (2) ◽  
pp. 213-219 ◽  
Author(s):  
Kimbroe J. Carter ◽  
Nathan P. Ritchey ◽  
Frank Castro ◽  
Leonard P. Caccamo ◽  
Edward Kessler ◽  
...  
Keyword(s):  
Health Care Professionals ◽  
Transition Probabilities ◽  
Early Stage ◽  
Treatment Options ◽  
The Elderly ◽  
Health State ◽  
Health States ◽  
Life Years ◽  
Simple Mastectomy ◽  
Health State Utilities

Purpose. To evaluate the post-lumpectomy treatment of a nonpalpable, stage I, T1b tumor, mammographically detected, in a 74-year-old woman without comorbidities. Methods. A Markov process, through 120 monthly cycles, was used to model patient progression through a treatment program, employing literature data and a health-outcome utility. Treatments considered were: observation; radiation totaling 5,000 cGy over six weeks; tamoxifen, 20 mg/day, for five years; simple mastectomy; and radiation therapy plus tamoxifen. Health states included absence of disease (NED), loco-regional recurrence, distant metastasis, age-sex-race (ASR)-adjusted death, cancer mortality, treatment complications, and post-mastectomy death. Transition probabilities were established from the literature. Health-state utilities were determined from the responses of health care professionals to a basic reference gamble. Results. Quality-adjusted life years (QALYs) were determined to be 8.19 for radiation plus tamoxifen, decreasing to 8.04 for mastectomy, a difference of only a 0.15 years (1.8 months). Sensitivity analysis, however, showed relative stability in the ranking among treatment options. Conclusion. Although the model showed little difference between QALYs with the treatments, the combination of radiation and tamoxifen provides the optimal therapy for this case.

scholarly journals Clinical features and prognostic factors in 71 eyes over 20 years from patients with Coats’ disease in Korea

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hyun Goo Kang ◽  
Jung Dong Kim ◽  
Eun Young Choi ◽  
Suk Ho Byeon ◽  
Sung Soo Kim ◽  
...  
Keyword(s):  
Clinical Features ◽  
Treatment Strategies ◽  
Onset Age ◽  
Long Term Outcomes ◽  
Asian Populations ◽  
Anti Vegf ◽  
Initial Treatment Period ◽  
Multivariable Regression ◽  
Coats Disease

AbstractThis retrospective study assesses the clinical features, treatment strategies, and long-term outcomes of patients with Coats’ disease in Korea. Multimodal imaging and medical records of consecutive patients treated between July 2000 and April 2020 at two tertiary centers were evaluated based on onset age (adult vs. childhood [< 18 years]). Factors associated with final visual acuity (VA) and risk of treatment failure were assessed. A total of 71 eyes of 67 patients were included, with subgrouping by onset age showing 45% childhood and 55% adult cases. Overall, Stage 2 disease was most common at presentation (76%), though childhood cases had more Stage 3b (22% vs. 3%,P = 0.02) and greater clock hours of retinal telangiectasia (7 vs. 5,P = 0.005). First-line treatment included laser (25%), combined laser/anti-VEGF (23%), cryotherapy (20%), surgery (16%), and anti-VEGF only (9%). Cryotherapy was associated with a higher risk for secondary interventions (OR 11.8,P < 0.001), required in 56% overall. Despite a 3-line VA decrease in 34% overall, adult cases had superior final VA (P = 0.037). Multivariable regression showed that the number of anti-VEGF injections performed during the initial treatment period was associated with a 9.4 letter improvement in vision (P = 0.041). We observed a higher proportion of adult-onset Coats’ disease than previously reported in other non-Asian populations. An aggressive treatment with the addition of anti-VEGF may yield the most favorable long-term visual outcomes.

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