Clinical Trial and Real-World Outcomes of Patients With Metastatic NSCLC in the Post-Platinum-Based Chemotherapy Failure Setting.

Introduction: A literature review was undertaken to identify clinical trials and real-world studies of patients with stage IV NSCLC who had progressed on or after treatment with platinum-based chemotherapy. Methods: The EMBASE and MEDLINE databases were used to search for English-language studies published between September 28, 2017, and September 28, 2021. Studies were included in the review if they (1) were clinical trials or real-world analyses of one or more treatment regimens for patients with stage IV NSCLC who had progressed on or after treatment with platinum-based chemotherapy, (2) contained an end point including efficacy, effectiveness, or safety, and (3) included 45 or more patients. Results: In total, there were 15 publications (nine unique trials and three real-world studies) included. Sample size ranged from 49 to 1253 patients. At least one treatment arm in eight of the nine clinical trials reported an overall response rate of ≥15%. Median progression-free survival (PFS) and overall survival ranged from 1.9 to 5.2 months and 5.4 to 15.4 months in clinical trials and 4.4 to 6.8 months and 8.3 to 18.0 months in real-world studies, respectively. Within studies reporting median PFS, a median PFS of more than or equal to 3 months was reported in eight of 11 clinical trials and both real-world studies. Discontinuation due to adverse events ranged from 1.9% to 18% across all included studies. Conclusions: Patients with stage IV NSCLC had limited response and a high burden of adverse events during treatment after progression on platinum-containing chemotherapy. There remains a pressing unmet need for additional, effective, and tolerable treatment options in this setting.

A systematic literature review of economic evaluations of pneumococcal conjugate vaccines in east and southeast Asia (2006-2019).

INTRODUCTION: Pneumococcal infections can lead to serious invasive diseases such as meningitis, septicemia and pneumonia, as well as milder but more common illnesses such as sinusitis and otitis media. The World Health Organization (WHO) recommends the inclusion of pneumococcal conjugate vaccines (PCVs) in infant National Immunization Program (NIP) programs worldwide. Decision-makers in Asian countries planning to introduce PCVs in their respective NIP will need a comprehensive evidence of effectiveness of PCVs at the population level and economic evidence including cost-effectiveness. AREAS COVERED: A systematic literature review (from 1/1/2016 to 10/11/2019) of PCVs in East and Southeast Asia to understand (1) the contributing factors to cost-effectiveness results of PCVs and (2) whether gaps in evidence exist suggesting why the region may have yet to implement full NIPs. EXPERT OPINION: In East and Southeast Asia, vaccination with PCVs was found to significantly reduce the mortality and morbidity of pneumococcal diseases and was cost-effective compared to no vaccination. Study assumptions, specifically vaccine local acquisition, the inclusion or exclusion of indirect effects (serotype replacement and herd effect), cross-protection, and protection against nontypeable haemophilus influenzae and serotype 3, were the main drivers of cost-effectiveness.

Health-Related Quality of Life for Patients Receiving Tumor Treating Fields for Glioblastoma.

BACKGROUND: To date, there has been no large-scale, real-world study of the health-related quality of life outcomes for patients using tumor treating fields (TTFields) therapy for glioblastoma (GBM) treatment. METHODS: A survey was mailed to 2,815 patients actively using TTFields for treatment of GBM in the USA (n = 2,182) and Europe (n = 633). The survey included patient-reported demographic and clinical information, as well as EuroQol's EQ-5D-5L and visual analogue scale (EQ-VAS) overall health score. RESULTS: A total of 1,106 applicable patients responded to the survey (USA = 782 and Europe = 324), with a mean age of 58.6 years (SD = 12.3). The average time since diagnosis and time using TTFields were 21.5 months (SD = 25.1) and 13.5 months (SD = 13.2), respectively. Over 61% of patients had been diagnosed at least 1 year prior and 28.4% at least 2 years prior; 45 patients (4.2%) had been diagnosed at least 5 years prior. Progressed disease was reported in 307 patients, while 690 reported non-progressed disease. Regression analyses showed that GBM disease progression and older age had predictable negative associations (p < 0.001) with most EQ-5D-5L dimensions and the EQ-VAS. However, longer time since diagnosis was associated with improved self-care (p < 0.05), usual activities (p < 0.01), and EQ-VAS (p < 0.05) overall and in patients with progressed disease (p < 0.01, p < 0.05, and p < 0.01, respectively). Additionally, longer time using TTFields was associated with improved mobility (p < 0.05), self-care (p < 0.001), usual activities (p < 0.01), and EQ-VAS (p < 0.01) overall; with improved EQ-VAS in progression-free patients (p < 0.05); and with improved mobility (p < 0.05), self-care (p < 0.01), usual activities (p < 0.05), and EQ-VAS (p < 0.05) in patients with progressed disease. CONCLUSION: This is the largest real-world study of patient-reported quality of life in GBM and TTFields treatment to date. It shows unsurprising negative associations between quality of life and disease progression and older age, as well as more novel, positive associations between quality of life and longer time since diagnosis and time using TTFields therapy.

The Cost-Effectiveness of 13-Valent Pneumococcal Conjugate Vaccine in Seven Chinese Cities.

Objective: This study estimates the cost-effectiveness of vaccination with the 13-valent pneumococcal conjugate vaccine (PCV13) among infants in Beijing, Shanghai, Shenzhen, Chengdu, Karamay, Qingdao, and Suzhou. Methods: A previously published cost-effectiveness model comparing vaccination with PCV13 to no vaccination was localized to the included Chinese cities. A systematic literature review was undertaken to identify age-specific incidence rates for pneumococcal bacteremia, pneumococcal meningitis, pneumonia, and otitis media (AOM). Age-specific direct medical costs of treating the included pneumococcal diseases were taken from the Chinese Health Insurance Association database. The base case analysis evaluated vaccine efficacy using direct effect and indirect effects (DE+ IDE). A subsequent scenario analysis evaluated the model outcomes if only DE was considered. A vaccination rate of 70% was used. The model reported outcomes over a one-year period after it was assumed the vaccine effects had reached a steady state (5-7 years after vaccine introduction) to include the direct and indirect effects of vaccination. Health outcomes were discounted at 5% during the steady-state period. Results: Vaccination with PCV13 was cost-effective in the base case analysis for all included cities with the incremental cost-effectiveness ratio (ICER) ranging from 1145 CNY(Shenzhen) to 15,422 CNY (Qingdao) per quality-adjusted life-year (QALY) gained. PCV13 was the dominant strategy in Shanghai with lower incremental costs and higher incremental QALYs. PCV13 remained cost-effective in the DE-only analysis with all ICERs falling below a cost-effectiveness threshold of three times GDP per capita in each city. Conclusions: Vaccination with PCV13 was a cost-effective strategy in the analyzed cities for both the DE-only and DE + IDE analyses. PCV13 became very cost-effective when a vaccination rate was reached where IDE is observed.

Relationship between transfusion burden, healthcare resource utilization, and complications in patients with beta-thalassemia in Taiwan: A real-world analysis.

BACKGROUND: This study utilized a population-based claims database to identify patients with beta-thalassemia and evaluate associations between transfusion burden, healthcare resource utilization (HCRU), and complications. STUDY DESIGN AND METHODS: Taiwan's National Health Insurance Research Database was used to identify patients with beta-thalassemia (ICD-10 D56.1) in 2016. Patients with a beta-thalassemia claim in 2016 were indexed into the study at their first claim on or after January 1, 2001 in the dataset through to December 31, 2016 and followed until the end of study. During the follow-up period, red blood cell transfusion (RBCT) units, HCRU, iron chelation therapy use, and beta-thalassemia-related complications incidence were recorded. Patients were grouped into transfusion burden severity cohorts based on average number of RBCT units per 12 weeks during follow-up: 0 RBCT units, >0 to <6 RBCT units (mild), ≥6 to <12 RBCT units (moderate), and ≥12 RBCT units (severe). RESULTS: A total of 2984 patients were included with mean follow-up of 6.95 years. Of these, 1616 (54.2%) patients had no claims for RBCT units, 1112 (37.3%) had claims for >0 to <6 RBCT units, 112 (3.8%) for ≥6 to <12 RBCT units, and 144 (4.8%) for ≥12 RBCT units per 12 weeks. Transfused patients had significantly more all-cause HCRU and iron chelation therapy compared with non-transfused patients during follow-up. Thalassemia-related HCRU and risk of liver, endocrine, cardiac, and renal complications were significantly and positively correlated with increases of RBCT units. DISCUSSION: Clinical and healthcare resource burden of patients with beta-thalassemia is closely related to transfusion burden.

Understanding the global measurement of willingness to pay in health.

Objective: To understand the different methodologies used to elicit willingness to pay for health and the value of a statistical life year through surveys. Methodology: A systematic review of the literature was undertaken to identify studies using surveys to estimate either willingness to pay for health or the value of a statistical life year. Each study was reviewed and the study setting, sample size, sample description, survey administration (online or face to face), survey methodology, and results were extracted. The results of the studies were then compared to any published national guidelines of cost-effectiveness thresholds to determine their accuracy. Results: Eighteen studies were included in the review with 15 classified as willingness to pay and 3 value of a statistical life. The included studies covered Asia (n = 6), Europe (n = 4), the Middle East (n = 1), and North America (n = 5), with one study taking a global perspective. There were substantial differences in both the methodologies and the estimates of both willingness to pay and value of a statistical life between the different studies. Conclusion: Different methods used to elicit willingness to pay and the value of a statistical life year resulted in a wide range of estimates.

The Cost of Hypoglycemia Associated With Type 2 Diabetes Mellitus in Taiwan.

OBJECTIVES: To quantify the incremental burden of patients with type 2 diabetes mellitus (T2DM) and a hypoglycemic event in Taiwan using the National Health Insurance Research Database. METHODS: Data from 2000 through 2013 with an index period of 2001 through 2012 from the National Health Insurance Research Database's 2-million-patient sample were used. Using a nested case-control study design, patients were indexed if they reported a diagnosis of T2DM during the index period. Patients with T2DM with a hypoglycemic event (defined by International Classification of Diseases, Ninth Revision, Clinical Modification codes) during the index period were identified. Patients with T2DM without a hypoglycemic event were included to form a 4:1 (controls to cases) matched cohort on the basis of age, sex, the Charlson Comorbidity Index, and the T2DM diagnosis date. Both cohorts were followed up for 1 year after the hypoglycemic event and had their treatment utilization, resource utilization, and healthcare costs measured. RESULTS: A total of 144 213 patients with T2DM were identified, with 3 651 (2.5%) recording a hypoglycemic event. Before matching, patients with T2DM with a hypoglycemic event were, on average, older (64.2 vs 56.6) and had higher mean CCI scores (2.4 vs 1.9) than did patients with T2DM without a hypoglycemic event. After matching, patients with T2DM and a hypoglycemic event incurred an additional $1353 in average direct healthcare costs during the 1 year of follow-up compared with the matched cohort. Patients with T2DM with hypoglycemia also spent an additional 5.9 days in the hospital during the follow-up period compared with the matched cohort. CONCLUSIONS: Patients with hypoglycemic events, on average, experienced a substantially higher economic burden than did their counterparts without a hypoglycemic event during the same period.

Estimating the response and economic burden of rheumatoid arthritis patients treated with biologic disease-modifying antirheumatic drugs in Taiwan using the National Health Insurance Research Database (NHIRD).

BACKGROUND: Previous studies in Taiwan utilizing the Taiwan's National Health Insurance Database (NHIRD) have estimated the direct healthcare costs of RA patients, but they have not focused on patients on bDMARDs, or considered patients' response to therapy. OBJECTIVES: The objective of this study was to estimate the rate of inadequate response for patients newly treated with biologic disease-modifying antirheumatic drugs (bDMARDs) as well as their costs and resource use. METHODS: Data were from the catastrophic illness file within the NHIRD from 1/1/2009 to 12/31/2013. Patients with RA, which was categorized by the presence of a catastrophic illness card, that were previously bDMARD-naïve, were included in this study if they initiated their first bDMARD during the index period. The index period included all of 2010, a pre-index period consisting of the index date- 365 days, and a follow-up period including the index date to 365 days post-index, were also included. Previously biologically-naïve patients were indexed into the study on the date of their first claim for a bDMARD. A validated algorithm was used to examine the rate of inadequate response (IR) in the biologically-naïve cohort of patients. Inadequate responders met one or more of the following criteria during their year of follow-up: low adherence (proportion of days covered <0.80); switched to or added a second bDMARD; added a new conventional synthetic DMARD (csDMARD); received ≥1 glucocorticoid injection; or increased oral glucocorticoid dosing. All-cause mean annual direct costs and resource use were measured in the year of follow-up. Costs were converted from NT$ to USD using 1 NT$ = 0.033 USD. RESULTS: A total of 818 patients with RA initiated their first bDMARD (54% etanercept and 46% adalimumab) in 2010. After one year of follow-up, 32% (n = 258) were classified as stable, 66% (n = 540) had an IR, and 2% (n = 20) were lost to follow-up. During the follow-up period mean annual total direct costs were $16,136 for stable patients compared to $14,154 for patients with IR. Mean annual non-medication direct costs were $937 for stable patients and $1,574 for patients with IR. Mean annual hospitalizations were higher for patients with IR (0.46) compared to stable patients (0.10) during the one year follow-up period. CONCLUSIONS: The majority of patients that were previously naïve to bDMARDs had an IR to their first bDMARD during the year of follow-up. Patients with an IR had numerically increased all-cause resource utilization and non-medication costs during the follow-up period compared to patients with stable disease. This level of IR suggests an unmet need in the RA treatment paradigm.

Epidemiology of pharmaceutically treated depression and treatment resistant depression in Taiwan.

Epidemiologic data on treatment resistant depression (TRD) in Asia-Pacific countries are limited. We estimated the incidence of TRD in Taiwan using a cohort of 704,265 adults randomly sampled from Taiwan's National Health Insurance Research database for 2005. TRD was defined as a patient having pharmaceutically treated depression (PTD) not adequately responding to 2 antidepressant (AD) regimens, i.e., AD regimens that were followed by other AD regimens. Among 2751 PTD subjects, 576 (20.94%, 95% CI: 19.46, 22.49) developed TRD, a proportion similar to that in North American studies. TRD incidence was 0.82 (95% CI: 0.75, 0.89) cases /1000 population in 2005, increased with age, and was higher in females than in males. SSRI's were the most frequently used ADs. Augmentation with antipsychotics was common. The median time from PTD onset (first AD medication) to TRD onset was 416 days but psychiatrists practicing in Taiwan indicated they would switch within <=3 months if an AD medication was not effective. We therefore repeated the analysis with a 6 months cap on time from onset of PTD to TRD. In this supplemental, post-hoc, analysis, 68 PTD subjects, 2.47%, (95% CI: 1.94, 3.10) developed TRD; i.e., 0.10 (95% CI: 0.08, 0.12) incident cases/1000 population.

The cost-effectiveness of a NSCLC patient assistance program for pemetrexed maintenance therapy in People's Republic of China.

BACKGROUND: Eli Lilly and the China Primary Health Care Foundation are currently implementing a patient assistance program (PAP) in China, which allows first-line nonsquamous non-small-cell lung cancer (NSCLC) patients who complete four cycles of pemetrexed induction therapy to receive free, continuous pemetrexed maintenance therapy. OBJECTIVE: To estimate the cost-effectiveness of pemetrexed maintenance therapy vs basic standard care (BSC) and the economic impacts of providing a PAP for pemetrexed maintenance therapy to NSCLC patients who have completed pemetrexed induction therapy in a Chinese health care setting. METHODS: We developed a novel decision-analytic model to evaluate the long-term costs and clinical efficacy of pemetrexed plus BSC vs BSC alone. We utilized a three-state (progression-free survival, progressed disease, and dead) partition survival model for both the clinical and economic aspects of the analysis. Cost and health utility estimates were derived from the literature. We performed a scenario analysis to estimate the real-world impact of introducing the PAP in China by comparing the use of the PAP vs non-PAP. Model uncertainty was evaluated using one-way and multivariate probabilistic sensitivity analysis. RESULTS: Compared to BSC, pemetrexed plus BSC resulted in a gain of 0.22 years of life (95% credible range [CR]: 0.04-0.46) and 0.13 quality-adjusted life years (95% CR: 0.04-0.26) per patient, at an increased cost of $28,105 (95% CR: -$22,720 to $48,646) without a PAP and $3,068 (95% CR: -$1,263 to $9,163) with a PAP. The incremental cost-effectiveness ratio for pemetrexed plus BSC vs BSC alone was cost-prohibitive at $222,700 for non-PAP, but cost-effective at $24,319 with a PAP. CONCLUSION: Our study suggests that maintenance pemetrexed therapy following pemetrexed induction for patients with advanced NSCLC is likely to be highly non-cost-effective in the absence of a PAP, but the pending implementation of the PAP promises to make it cost-effective, with a >90% probability of cost-effectiveness at a Chinese willingness-to-pay threshold per quality-adjusted life year.

Cost-effectiveness Study of Celecoxib for Osteoarthritis in China / 中国药房

OBJECTIVE:To evaluate cost-effectiveness of celecoxib for osteoarthritis(OA)in China. METHODS:OA cost-ef-fectiveness analysis model developed by National Institute for Health and Clinical Excellence(NICE)was adopted using celecoxib, diclofenac+PPIs as control. Related risk Zof adverse event was from CONDOR trials.The effectiveness was measured by QALY. Costs and QALYs were discounted annually at 4.76%. RESULTS:Celecoxib had a cost of $3 591 and 8.826 QALYs while diclofe-nac+PPIs had a cost of $3 674 and 8.830 QALYs. The incremental costs and QALYs of celecoxib to diclofenac+PPIs were -$83 and -0.004 QALYs,respectively. The incremental cost-effectiveness ratio(ICER)for diclofenac+PPIs to celecoxib was$23 258/QALY. The results of single factor sensitivity analysis and probability sensitivity analysis showed that drug cost was driving factor of IC-ER,and the results of two therapy plans were similar. CONCLUSIONS:Celecoxib is a less costly alternative than diclofenac+PPIs. The difference in QALYs between celecoxib and diclofenac+PPIs is extremely small,so celecoxib is likely to be cost-effec-tive for OA patients.

Precision Health Economics and Outcomes Research to Support Precision Medicine: Big Data Meets Patient Heterogeneity on the Road to Value.

The "big data" era represents an exciting opportunity to utilize powerful new sources of information to reduce clinical and health economic uncertainty on an individual patient level. In turn, health economic outcomes research (HEOR) practices will need to evolve to accommodate individual patient-level HEOR analyses. We propose the concept of "precision HEOR", which utilizes a combination of costs and outcomes derived from big data to inform healthcare decision-making that is tailored to highly specific patient clusters or individuals. To explore this concept, we discuss the current and future roles of HEOR in health sector decision-making, big data and predictive analytics, and several key HEOR contexts in which big data and predictive analytics might transform traditional HEOR into precision HEOR. The guidance document addresses issues related to the transition from traditional to precision HEOR practices, the evaluation of patient similarity analysis and its appropriateness for precision HEOR analysis, and future challenges to precision HEOR adoption. Precision HEOR should make precision medicine more realizable by aiding and adapting healthcare resource allocation. The combined hopes for precision medicine and precision HEOR are that individual patients receive the best possible medical care while overall healthcare costs remain manageable or become more cost-efficient.

Estimating the Economic Burden of Rheumatoid Arthritis in Taiwan Using the National Health Insurance Database.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by inflammation and destruction of the joints. OBJECTIVES: This research aims to estimate the economic burden of RA in Taiwan. METHODS: The National Health Insurance Research Database (NHIRD), a claims-based dataset encompassing 99 % of Taiwan's population, was applied. We used a micro-costing approach for direct healthcare costs and indirect social costs by estimating the quantities and prices of cost categories. Direct costs included surgeries, hospitalizations, medical devices and materials, laboratory tests, and drugs. The costs and quantities of the direct economic burden were calculated based on 2011 data of NHIRD. We identified RA patients and a control cohort matched 1:4 on demographic and clinical covariates to calculate the incremental cost related to RA. Indirect costs were evaluated by missed work (absenteeism) and worker productivity (presenteeism). For the indirect burden, we estimated the rate of absenteeism and presenteeism from a patient survey. Costs were presented in US dollars (US$1 = 30 TWD). RESULTS: A total of 41,269 RA patients were included in the database with incremental total direct cost of US$86,413,971 and indirect cost of US$138,492,987. This resulted in an average incremental direct cost of US$2050 per RA patient. Within direct costs, the largest burdens were associated with drugs (US$73,028,944), laboratory tests (US$6,132,395), and hospitalizations (US$3,208,559). For indirect costs, absenteeism costs and presenteeism costs were US$16,059,681 and US$114,291,687, respectively. CONCLUSIONS: The economic burden of RA in Taiwan is driven by indirect healthcare costs, most notably presenteeism.

The Cost-Effectiveness of Pregabalin Versus Gabapentin for Peripheral Neuropathic Pain (pNeP) and Postherpetic Neuralgia (PHN) in China.

INTRODUCTION: Postherpetic neuralgia (PHN), a type of peripheral neuropathic pain (pNeP), is the most common complication of herpes zoster. The objective of this analysis was to determine the cost-effectiveness of pregabalin compared with gabapentin in pNeP and PHN in China. METHODS: We developed a China-localized 12-week simulation model to determine the cost-effectiveness of pregabalin compared to gabapentin in 1000 patients with pNeP and PHN. We utilized a questionnaire of Chinese key opinion leaders to estimate the pre-treatment distribution of pain scores for pNeP and PHN. Treatment outcomes for pregabalin and gabapentin were acquired from the published literature. RESULTS: Treatment with pregabalin lead to 12-week decreases in pain scores of 0.6 (pNeP) and 0.7 (PHN) when compared to patients receiving gabapentin, at an incremental cost per additional day of mild/no pain of $45. The difference in mean days of no or mild pain, moderate pain, and severe pain was 8.8, -5.7, and -3.1, when comparing pregabalin and gabapentin, respectively. Pregabalin had more mean days with a >30% (7.71 days), 40% (8.97 days), and 50% reduction (9.97 days) in pain when compared with gabapentin. In the pNeP scenario, pregabalin was associated with a lower average pain score compared with gabapentin (3.91 vs. 4.55). The difference in mean days of no or mild pain, moderate pain, and severe pain was 9.39, -5.56, and -3.82, when comparing pregabalin and gabapentin, respectively. Pregabalin had more mean days with a >30% (8.77 days), 40% (9.81 days), and 50% reduction (10.55 days) in pain when compared with gabapentin. CONCLUSION: Pregabalin is an effective treatment for PHN and even for pNeP extensively, but at increased cost. It leads to improved outcomes including lower pain scores and more days with no or mild pain. FUNDING: Pfizer, China.

The cost reduction in hospitalization associated with paliperidone palmitate in the People's Republic of China, Korea, and Malaysia.

BACKGROUND: Schizophrenia results in substantial health care utilization costs. Much of these costs can be attributed to health care use resulting from nonadherence to treatment, relapse, and hospitalization. AIMS OF THE STUDY: The objective of this research is to further estimate the health care resource utilization costs of patients with schizophrenia in the People's Republic of China, Korea, and Malaysia with a specific focus on the reduction in hospitalization costs associated with the use of long-acting, injectable paliperidone palmitate (PP) relative to alternative treatment medications. METHODS: The study focuses exclusively on the estimated reduction in hospitalization days following treatment with PP and the potential associated cost savings. Cost analysis was done using a payer's perspective and only includes direct health care costs associated with hospitalization. Localized cost data were taken from published sources, and health care utilization was estimated based on a clinical study conducted in countries in the Asia-Pacific region. People's Republic of China, Korea, and Malaysia had the highest number of patients enrolled in the clinical study, and thus were chosen for this research. Analysis looked at 12-month and 18-month periods following initial treatment with PP relative to a retrospective 12-month period utilizing alternative treatment medications. RESULTS: Results suggest that reductions in hospital utilization cost over 12 months may occur through the use of PP relative to alternatives-ranging from $1,991 for the People's Republic of China to $6,698 for Korea and $6,716 for Malaysia. CONCLUSION: Given the substantial costs associated with the treatment of schizophrenia both worldwide and in Asia, it is important to fully understand the costs and outcomes associated with various treatment options. In this research, we have specifically analyzed the direct health care cost savings associated with hospital utilization for patients taking PP relative to alternative treatment methods. The results suggest that reductions in hospital utilization cost were associated with PP treatment, likely largely due to increased adherence to treatment.

Modelling the long-term outcomes of bariatric surgery: A review of cost-effectiveness studies.

Obesity, defined as BMI ≥30 kg/m(2), affects over 30% of the United States adult population and has been declared an epidemic by the Centers for Disease Control. Bariatric surgery is a treatment option to reduce excess weight and is available to individuals with BMI greater than 40 kg/m(2), or 35 kg/m(2) with obesity-related comorbidities. As surgical options have become more common, researchers have analysed the long-term cost-effectiveness of these procedures. However, the follow-up data on patients is limited, and modelers need to forecast lifetime costs and outcomes for this chronic disease. In this chapter, we conduct a systematic literature review of cost-effectiveness studies on bariatric surgery to understand the forecasting methods used in practice. We identified six unique studies, which used statistical models, Markov models, or assumptions to forecast lifetime outcomes. We discuss each of the approaches, so clinicians, policy-makers, and payers can make informed interpretations based on the models.