論文 - 後藤　励

The effects of patient cost-sharing on health expenditure and health among older people: Heterogeneity across income groups

Kato H., Goto R., Tsuji T., Kondo K.

European Journal of Health Economics （European Journal of Health Economics）  23 （ 5 ） 847 - 861 2021年

ISSN  16187598

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Despite rapidly rising health expenditure associated with population aging, empirical evidence on the effects of cost-sharing on older people is still limited. This study estimated the effects of cost-sharing on the utilization of healthcare and health among older people, the most intensive users of healthcare. We employed a regression discontinuity design by exploiting a drastic reduction in the coinsurance rate from 30 to 10% at age 70 in Japan. We used large administrative claims data as well as income information at the individual level provided by a municipality. Using the claims data with 1,420,252 person-month observations for health expenditure, we found that reduced cost-sharing modestly increased outpatient expenditure, with an implied price elasticity of – 0.07. When examining the effects of reduced cost-sharing by income, we found that the price elasticities for outpatient expenditure were almost zero, – 0.08, and – 0.11 for lower-, middle-, and higher-income individuals, respectively, suggesting that lower-income individuals do not have more elastic demand for outpatient care compared with other income groups. Using large-scale mail survey data with 3404 observations for self-reported health, we found that the cost-sharing reduction significantly improved self-reported health only among lower-income individuals, but drawing clear conclusions about health outcomes is difficult because of a lack of strong graphical evidence to support health improvement. Our results suggest that varying cost-sharing by income for older people (i.e., smaller cost-sharing for lower-income individuals and larger cost-sharing for higher-income individuals) may reduce health expenditure without compromising health.

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Risk preferences, rationality of choices, and willingness to pay for preventive medicine in patients with graves’ thyrotoxicosis

Emoto N., Okazaki-Hada M., Yamaguchi Y., Okajima F., Goto R., Sugihara H.

Patient Preference and Adherence （Patient Preference and Adherence）  15   1971 - 1979 2021年

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Purpose: Patients with thyrotoxicosis show neuropsychological changes, and these may damage the quality of informed consent in clinical practice. Therefore, we examined patients’ real-life preferences to assess whether change in risk preferences was dependent on thyroid function state. Patients and Methods: The participants were 86 patients who were newly diagnosed with Graves’ thyrotoxicosis between 1 January and 31 December 2018 (group A), and an additional 33 euthyroid patients diagnosed before 2018 (group B). In a survey conducted via a questionnaire based on the concept of behavioral economics, we sought to determine risk preferences, rationality of choices, and other relevant factors. An identical second survey was completed 6–12 months later by 36 patients in group A after their thyroid functions had been normalized by treatment, and by 11 euthyroid patients in group B. We performed paired analysis of the first and second surveys in 32 patients of group A and single regression analysis of a total of 140 surveys obtained from 119 patients by combining the first and second surveys of groups A and B with serum level of FT3 as an independent variable. Results: The paired analysis indicated that there was no significant difference in any survey item. The single regression analysis revealed that willingness-to-pay (WTP) for preventive medicine and monthly average out-of-pocket (OOP) expenditure on medical care were both significantly positively associated with serum level of FT3. Patients in the hyperthyroid state tend to have high WTP for preventive medicine, which may be accelerated by the anchoring effect of OOP expenditure. Conclusion: Almost all risk preferences of patients with Graves’ disease are constant, rational, and reproducible in the hyperthyroid and euthyroid states. However, medical professionals should be aware that the willingness of patients with thyrotoxicosis to pay for medical costs may change after the normalization of thyroid function.

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Cost-effectiveness of extracorporeal cardiopulmonary resuscitation for out-of-hospital cardiac arrest: A multi-centre prospective cohort study

Matsuoka Y., Goto R., Atsumi T., Morimura N., Nagao K., Tahara Y., Asai Y., Yokota H., Ariyoshi K., Yamamoto Y., Sakamoto T.

Resuscitation （Resuscitation）  157   32 - 38 2020年12月

ISSN  03009572

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Aim: Extracorporeal cardiopulmonary resuscitation (ECPR) is an evolving resuscitative method for refractory cardiopulmonary arrests. However, considering the substantial healthcare costs and resources involved, there is an urgent need for a full economic evaluation. We therefore assessed the cost-effectiveness of ECPR for refractory ventricular fibrillation/pulseless ventricular tachycardia (VF/pVT). Methods: We developed a decision model to estimate lifetime costs and outcomes for out-of-hospital cardiac arrest patients with VF/pVT who received either ECPR or conventional cardiopulmonary resuscitation. Quality-adjusted life-years (QALY) was used as the main outcome measure. This model was a combination of a decision tree model for the acute phase based on a prospective observational study (SAVE-J study), together with a Markov model for long-term follow-up periods extrapolated from published data. To evaluate the robustness of this model, we conducted a comprehensive deterministic sensitivity analysis (DSA) and a probabilistic sensitivity analysis (PSA). Results: ECPR was cost-effective, with an incremental cost of ¥3,521,189 (Є30,227), an incremental effectiveness of 1.34 QALY, and an incremental cost-effectiveness ratio of ¥2,619,692 (Є22,489) per QALY gained. DSA revealed that the present model was most sensitive to probability of Cerebral Performance Category 1 after ECPR (¥2,153,977/QALY to ¥3,186,475/QALY), patient age (¥2,170,112/QALY to ¥3,334,252/QALY), and long-term medical cost for modified Rankin Scale 0 (¥2,280,352/QALY to ¥2,855,330/QALY). PSA indicated ECPR to be cost-effective and below the willingness-to-pay threshold of ¥5,000,000 with an 86.7 % possibility. Conclusions: ECPR was an economically acceptable resuscitative strategy, and the results of the present study were robust even when considering the uncertainty of all parameters.

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Socio-demographic determinants of motorcycle speeding in Maha Sarakham, Thailand

Hong V., Iwamoto S.K., Goto R., Young S., Chomduangthip S., Weeranakin N., Nishi A.

PLoS ONE （PLoS ONE）  15 （ 12 December ）  2020年12月

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Thailand has the highest road traffic fatality rate in Southeast Asia, making road safety a critical public health concern. A 2015 World Health Organization (WHO) Report showed that speeding behavior was the most important determinant for road traffic crashes in Thailand. Here, we aimed to examine associations of socio-demographic factors (gender, age, socioeconomic status) with self-reported motorcycle speeding behavior. Additionally, we examined a potential role of time discounting and risk preference as mediators in the association of socio-demographic factors with speeding. We used data obtained from the Mahasarakham University Social Network Survey 2018 (MSUSSS) (N = 150). We ran linear network autocorrelation models (lnam) to account for the data's social network structure. We found that males are more likely than females to engage in speeding behavior (β = 0.140, p = 0.001) and to discount the future (β = 5.175, p = 0.017). However, further causal mediation analysis showed that time discounting does not mediate the gender-speeding association (p for mediation = 0.540). Although socioeconomic status (subjective social class) was not associated with speeding (β = 0.039, p = 0.177), age was marginally associated with speeding (β = 0.005, p = 0.093). Future studies may consider using a larger sample.

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Prevalence of problem gambling among Japanese adults

Mori T., Goto R.

International Gambling Studies （International Gambling Studies）  20 （ 2 ） 231 - 239 2020年05月

ISSN  14459795

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The prevalence of problem gambling has garnered considerable interest in numerous developed countries. In Japan, problem gambling may be far more prevalent than in other developed countries; however, there is little empirical research confirming this. Therefore, we estimated the prevalence of problem gambling in Japan using a standardized screening tool: The South Oaks Gambling Screen Revised (SOGS-R) and investigated the association between problem gambling and demographics such as gender, age, marital status, income, and educational background. We believe this study is necessary because gambling is a growing social problem in Japan that could worsen with the expected introduction of casinos in Japan due to the legalization of casino gambling in December 2016. Therefore, we surveyed participants’ experience of casino games both on the internet and abroad. Cross-sectional data were collected via a web-based survey of 6576 Japanese adults 20 years old and older. We found that the prevalence rate of problem gambling in Japan was significantly high from an international perspective. Restricting casino accessibility for individuals with high-risk factors could be effective in reducing gambling problems.

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Cost-effectiveness of rivaroxaban versus warfarin for stroke prevention in non-valvular atrial fibrillation in the Japanese healthcare setting

Hori M., Tanahashi N., Akiyama S., Kiyabu G., Dorey J., Goto R.

Journal of Medical Economics （Journal of Medical Economics）  23 （ 3 ） 252 - 261 2020年03月

ISSN  13696998

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Aims: This article aimed to examine the cost-effectiveness of rivaroxaban in comparison to warfarin for stroke prevention in Japanese patients with non-valvular atrial fibrillation (NVAF), from a public healthcare payer’s perspective. Materials and methods: Baseline event risks were obtained from the J-ROCKET AF trial and the treatment effect data were taken from a network meta-analysis. The other model inputs were extracted from the literature and official Japanese sources. The outcomes included the number of ischaemic strokes, myocardial infarctions, systemic embolisms and bleedings avoided, life-years, quality-adjusted life-years (QALYs), incremental costs and incremental cost-effectiveness ratio (ICER). The scenario analysis considered treatment effect data from the same network meta-analysis. Results: In comparison with warfarin, rivaroxaban was estimated to avoid 0.284 ischaemic strokes per patient, to increase the number of QALYs by 0.535 per patient and to decrease the total costs by ¥118,892 (€1,011.11) per patient (1 JPY = 0.00850638 EUR; XE.com, 7 October 2019). Consequently, rivaroxaban treatment was found to be dominant compared to warfarin. In the scenario analysis, the ICER of rivaroxaban versus warfarin was ¥2,873,499 (€24,446.42) per QALY. Limitations: The various sources of data used resulted in the heterogeneity of the cost-effectiveness analysis results. Although, rivaroxaban was cost-effective in the majority of cases. Conclusion: Rivaroxaban is cost-effective against warfarin for stroke prevention in Japanese patients with NVAF, giving the payer WTP of 5,000,000 JPY.

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Current treatment patterns and medical costs for multiple myeloma in Japan: a cross-sectional analysis of a health insurance claims database

Uno S., Goto R., Suzuki K., Iwasaki K., Takeshima T., Ohtsu T.

Journal of Medical Economics （Journal of Medical Economics）  23 （ 2 ） 166 - 173 2020年02月

ISSN  13696998

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Aims: Various drugs have recently been launched for the treatment of multiple myeloma (MM). This increase in the number of treatment options has potentially changed treatment patterns and medical costs for patients with MM. Japanese public health insurance claims were analyzed to examine the change in the treatment patterns of MM drugs and medical costs per patient. Materials and methods: A claims database provided by Medical Data Vision was used, which includes data from ∼20 million patients from >300 acute care hospitals across Japan. The type of MM drugs prescribed and medical costs for patients with MM between April 2008 and December 2016 were examined using monthly cross-sectional analyses. Patients with an International Classification of Diseases, 10th Revision (ICD-10) diagnosis code of C90.0 were classified as having MM. MM drugs were defined by generic names. Results: In total, 19,137 patients with MM (average age at first diagnosis: 69.6 years; percentage of women: 47.9%) were identified from the database. The percentage of patients prescribed each MM drug changed substantially as novel drugs were launched. Total medical costs increased until 2010, then stabilized. MM drug costs increased from approximately 2010, but costs for other care decreased, particularly for hospitalization (including surgery). Limitations: The database contained data from large, acute care hospitals, which may have caused bias in terms of patients’ clinical history and disease severity. Conclusions: Total medical costs for MM have remained stable since 2010. MM drug costs increased, but costs for other care decreased after the launch of lenalidomide in 2010 and other drugs in 2015 and later. More detailed research is required to confirm whether the launch of novel drugs caused the changes in medical costs.

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Irrational responses to risk preference questionnaires by patients with diabetes with or without retinopathy and comparison with those without diabetes

Emoto N., Soga A., Fukuda I., Tanimura-Inagaki K., Harada T., Koyano H.M., Goto R., Sugihara H.

Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy （Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy）  13   4961 - 4971 2020年

　概要を見る

Purpose: The risk preferences of patients with diabetes have profound effects on the progression of complications. The present study aimed to clarify whether the preferences of patients with diabetes and retinopathy are deliberately risk-seeking or irrational and whether this propensity is specific to those with retinopathy or is also found in patients without retinopathy compared with those without diabetes. Patients and Methods: A total of 394 patients with diabetes (264 without retinopathy and 130 with retinopathy) and 198 patients without diabetes agreed to participate in this survey. The questions were modified versions of those from the Japan Household Survey on Consumer Preferences and Satisfaction, which sought to determine the participants’ personal socioeconomic status and risk preferences. In the questionnaires, responses were analyzed by determining the participants’ willingness to pay for a lottery ticket and for an insurance policy. Irrational responses were defined as violations of two axioms of the Expected Utility Theory: completeness and transitivity. Results: The incidence of irrational responses increased with age and was associated with educational level. The incidence of irrational responses was significantly higher in patients with retinopathy than in those without retinopathy after adjusting for age and educational level. There was no significant difference in the incidence of irrational responses between patients with diabetes but without retinopathy and those without diabetes. Conclusion: The risk-seeking behavior of patients with diabetes and retinopathy was not deliberate but was irrational under uncertainty. Medical professionals should be aware of their patients’ propensity to make irrational decisions, which is an important risk factor for the progression of retinopathy in patients with diabetes regardless of age and educational level.

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Nudging patients with chronic kidney disease at screening to visit physicians: A protocol of a pragmatic randomized controlled trial

Fukuma S., Ikenoue T., Sasaki S., Saigusa Y., Misumi T., Saito Y., Yamada Y., Goto R., Taguri M.

Contemporary Clinical Trials Communications （Contemporary Clinical Trials Communications）  16 2019年12月

ISSN  24518654

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Background/Aims: Strategies for an effective intervention after chronic kidney disease (CKD) screening have not been well examined. We describe the rationale and design of a protocol of a pragmatic randomized controlled trial (RCT) to test the effect of a behavioral intervention using the nudge approach in behavioral economics on CKD patients’ visiting behaviors to physicians and change in their kidney function after CKD screening. Methods: The RCT will include CKD patients (N = 4500) detected at screening (estimated glomerular filtration rate [eGFR] <60 mL/min/1.74 m2 or urine protein ≥1+), aged 40–63 years. The two intervention groups will receive a “usual letter” and “nudge-based letter,” while the control group will only receive a conventional follow-up. Our primary outcome is proportion of patients’ visiting physicians for 6 months after the intervention; the secondary outcome is change in the eGFR at 2 years after the intervention. Results: We developed an efficient intervention program after CKD screening and designed the pragmatic RCT to assess its effectiveness in the real world. Our trial is unique in that it investigates the effect of the nudge approach in behavioral economics. By the end of 2018, we have enrolled 1,692 participants, and randomized 677 participants into the usual letter group, 677 participants into the nudge-based letter group, and 338 participants into the control group. We have confirmed that health checkup data could identify a large number of eligible participants. Conclusion: The trial's results will contribute to filling in the gap between screening and subsequent medical interventions for preventing CKD progression.

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Willingness to pay for QALY: perspectives and contexts in Japan

Igarashi A., Goto R., Yoneyama-Hirozane M.

Journal of Medical Economics （Journal of Medical Economics）  22 （ 10 ） 1041 - 1046 2019年10月

ISSN  13696998

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Objectives: Theoretically, willingness-to-pay (WTP) for quality-adjusted life years (QALY) can vary depending on social and personal preferences and on ex-ante and ex-post settings. However, empirical investigations into the theoretical differences are lacking. In Japan, setting the threshold has been controversial since a pilot project to implement health technology assessments (HTA) launched in 2016. The study aim is to estimate WTP values for one additional QALY from different perspectives, health statuses, and contexts to confirm the difficulty in setting a uniform price threshold using WTP. Methods: More than 1,000 respondents representing a cross-section of the Japanese population answered each of nine questionnaire decks in an online panel. WTP values were estimated on three different perspectives (personal, social, and socially inclusive) and on two contexts (ex-ante and ex-post). This study primarily used the non-parametric spike model based on double-bounded dichotomous choice (DBDC) settings to obtain the conditional WTP values. Results: WTP per QALY was higher in the severe health status than in the moderate health status from all perspectives. Respondents from the socially inclusive perspective estimated the highest WTP value for a new drug. Respondents were also asked about life-threatening diseases in ex-post and ex-ante. The WTP value in ex-ante was higher than in ex-post, and demographic factors affecting the WTP were different in both situations. The various WTP values were obtained from these surveys. Limitations: The analysis was based on data collected from an internet panel, which could be biased. There is also a risk that respondents answered the questionnaire differently if asked in everyday situations. Conclusion: Use of a uniform price threshold may not be appropriate in policy settings, because it may not reflect diverse preferences based on different situations, such as disease type and severity. Setting a price threshold as Japan institutes an HTA system requires further research.

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Impact of improved price transparency on patients' demand of healthcare services

Kobayashi D., Goto R., Tsugawa Y.

Social Science and Medicine （Social Science and Medicine）  235 2019年08月

ISSN  02779536

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Evidence is limited and mixed as to how improved price transparency affects patients' demand for healthcare. Price transparency usually affects both the supply and the demand side of healthcare. However, in Japan—where healthcare providers cannot compete on prices—we can examine an independent impact of price transparency on patients' demand for healthcare. The aim of this study is to investigate the impact of improved price transparency on patients' demand for healthcare. We conducted an experiment by presenting patients with the “price list” of individual healthcare services. We provided the price list for a limited time and compared the healthcare spending and utilization of care between these patients who were provided the price list (patients who visited between the first and third week of January in 2016) versus those who were not (patients who visited during the same period in 2015 or 2017), adjusting for potential confounders. A total of 1053 patients were analyzed (27.5% were provided the price list). We found that improved price transparency was associated with a higher total cost per patient (adjusted difference, +16.1%; 95%CI, +0.6% to +34.0%; p = 0.04). We also found that improved price transparency was associated with higher costs related to laboratory tests and imaging studies, and a larger total number of items of blood tests and urine tests. By conducting an experiment in a real-world setting, we found that improved price transparency paradoxically increased the utilization of healthcare services in Japan. These findings suggest that when prices are relatively low, as is the case in Japan, reduced uncertainty about the prices of healthcare service may make patients comfortable requesting more healthcare services.

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From fragmentation toward integration: A preliminary study of a new long-term care policy in a fast-aging country

Chiu T.Y., Yu H.W., Goto R., Lai W.L., Li H.C., Tsai E.T., Chen Y.M.

BMC Geriatrics （BMC Geriatrics）  19 （ 1 ）  2019年06月

　概要を見る

Background: Taiwan, one of the fastest-aging countries in the world, started implementing version 1.0 of its long-term care (LTC) plan in 2008. In 2017, LTC Plan 2.0 began a new era with its goal to integrate Taiwan's fragmented LTC service system. LTC Plan 2.0 also aims to establish an integrated community-based LTC system incorporating both health care and disability prevention. This three-tier model consists of the following: two LTC services with a day-care center as their base and case management (Tier A), a day-care center and a single LTC service (Tier B), and LTC stations that provide primary prevention services and respite services for frail community-dwelling older adults to prevent further disabilities (Tier C). A defined cluster of agencies in a local area works together as a Tier ABC team. LTC Plan 2.0 is a new policy for Taiwan, and hence it is important to understand the agencies' initial difficulties with implementation and identify future challenges to help further policy development. Methods: This preliminary study explored the challenges to implementing LTC 2.0 through in-depth interviews based on Evashwick's integration mechanisms with representatives from three service teams. We interviewed three chief executive officers and three case managers. Results: We found that the LTC Plan 2.0 mechanisms for service integration have been insufficiently implemented. Recommendations include (1) Build up the trust between agencies and government, avoid duplication of LTC services within Tier ABC team, and encourage agencies within a team to create a shared administrative system with the same mission and vision. (2) Clarify the roles and responsibilities of government care managers and agency case managers. (3) Provide an integrated information system and create an official platform for sharing client records across different agencies and caregivers. (4) Establish a tool and platform to track the budget and payment across different levels of service as soon as possible. Conclusion: There is an increased demand for LTC services in Taiwan because of its rapidly aging population. Our findings shed some light on the challenges to developing integrated LTC services and thus may help both policymakers and service providers find ways to overcome these challenges.

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Comparison of Equity Preferences for Life Expectancy Gains: A Discrete Choice Experiment among the Japanese and Korean General Public

Goto R., Mori T.

Value in Health Regional Issues （Value in Health Regional Issues）  18   8 - 13 2019年05月

ISSN  22121099

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Background: Setting priorities for limited public resources has become a topic of heated discussion the world over. Assigning different weights for the health gains of different population groups allows for equity considerations in cost-effectiveness analysis. However, only a few empirical works have elicited the preferences of the general public. Objective: To compare the equity preferemce assigned by Japanese and Koreans. Methods: We conducted a Web-based survey in March 2013, including a discrete choice experiment, to elicit the equity preferences of the general public for the life expectancy gains of different population groups. We selected attributes and designed the experiment following Norman et al.'s study (Norman R, Hall J, Street D, Viney R. Efficiency and equity: a stated preference approach. Health Econ 2013;22:568–81). Accordingly, we analyzed preference for sex, smoking status, lifestyle, caring status, income, and age. Results: The Japanese assigned a higher preference for males (P < 0.001), nonsmokers (P < 0.001), those with lower income (P < 0.001), and carers (P < 0.001), and they assigned a lower preference for those with a life expectancy of 60 years (P = 0.002) and 75-year-olds (P < 0.001). Koreans have the same patterns of preference for lower income (P < 0.001), caring (P < 0.001), and smoking status (P = 0.026). However, they prefer both sexes (P = 0.331) and different age groups equally. In both countries, respondents tend to prefer groups with characteristics similar to their own. Conclusions: People from the two Asian developed countries, with universal health insurance, show different equity preferences. These may reflect the variations in cultural background and coverage of health care services.

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Estimating the Net Utility Gains Among Donors and Recipients of Adult Living Donor Kidney Transplant

Hiragi S., Goto R., Tanaka Y., Matsuyama Y., Sawada A., SakaI K., Miyata H., Tamura H., Yanagita M., Kuroda T., Ogawa O., Kobayashi T.

Transplantation Proceedings （Transplantation Proceedings）  51 （ 3 ） 676 - 683 2019年04月

ISSN  00411345

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Objectives: Living donor kidney transplant relieves the disease burden of patients with end-stage renal disease but may shorten donor life expectancy; however, their quality of life (QOL) is preserved. Nevertheless, the magnitude of the net gain of this procedure is unknown. We evaluated the QOL of both donors and recipients concurrently and calculated the net utility gain. Methods: We recruited 210 subjects who visited the kidney transplantation clinic of a university hospital. Subjects were asked to complete the 5-level EQ-5D-based questionnaire, and patient characteristics were extracted from their medical records. We performed multivariate tobit models analysis to evaluate the QOL change caused by transplant surgery and subsequently ran computational simulations to determine the net utility gains of donors and recipients. We also performed sensitivity analyses. Results: After excluding 16 answers with missing data, we analyzed 203 answers in total. After the transplant surgery, recipients gained 0.07 in utility value while donors lost 0.04. In the net utility analysis, we found that the quality-adjusted life years gained ranged from 7.2 to 7.8 in the most favorable case observed in the combination of middle-aged recipients and elderly donors. Assuming no utility discount, the most favorable combination was that with older donors and younger recipients. Conclusions: These findings indicated that the QOL improvement in recipients was larger than the loss among donors. When calculating the net utilities, a combination of middle-aged recipients and elderly donors yielded the largest net utility, but this was likely derived from assumption in the discount of QOL.

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The impact of anti-vascular endothelial growth factor agents on visual impairment/blindness prevention in patients with diabetic macular edema and on associated patient and caregiver burden in Japan

Kitano S., Sakamoto T., Goto R., Fukushima A., Vataire A.L., Hikichi Y.

Journal of Medical Economics （Journal of Medical Economics）  22 （ 3 ） 254 - 265 2019年03月

ISSN  13696998

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Aims: To estimate the impact of anti-vascular endothelial growth factor (VEGF) agents on visual impairment and blindness avoided in patients with diabetic macular edema (DME) and on associated patient and caregiver productivity loss in Japan. Methods: This study compared the impact of current care (estimated at 53.8% utilization of anti-VEGF agents using current data) with that of hypothetical care (characterized by a higher utilization of anti-VEGF agents [80.0%], as estimated by an expert panel) of DME patients. A population-based Markov model (two-eye approach) simulated visual acuity (Early Treatment Diabetic Retinopathy Study [ETDRS] letters) transitions over 5 years with DME treatments (intravitreal aflibercept, ranibizumab, and triamcinolone acetonide, and grid/focal laser) in patients with DME. Patient and caregiver productivity loss was determined using the human capital method. Results: In total, 570,000 DME patients were included in the model over 5 years. Increased utilization of anti-VEGF agents resulted in 6,659 fewer cases of severe visual impairment (SVI; 26–35 ETDRS letters) or blindness (0–25 ETDRS letters) compared with the current care approach (26,023 vs 32,682 cases; 20.38% reduction) over this period. Increased utilization of anti-VEGF agents also contributed to productivity loss savings of ¥12.58 billion (US $115.64 million) (i.e., 17.01%) at the end of year 5. The total overall saving over 5 years was ¥45.83 billion (US $421.27 million) (13.45%). Limitations: Few Japanese data were available, and assumptions were made for some inputs. Vision changes dependent on the function of both eyes were not studied. Only intravitreal (not sub-Tenon’s) injections of triamcinolone were considered in this model. Direct costs were not considered. Conclusions: Increased utilization of anti-VEGF agents can reduce SVI and legal blindness in patients with DME in Japan. This would also be associated with substantial savings in patient and caregiver productivity loss.

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The effect of model selection on cost-effectiveness research: A comparison of kidney function-based microsimulation and disease grade-based microsimulation in chronic kidney disease modeling

Hiragi S., Tamura H., Goto R., Kuroda T.

BMC Medical Informatics and Decision Making （BMC Medical Informatics and Decision Making）  18 （ 1 ）  2018年11月

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Background: Cost effectiveness research is emerging in the chronic kidney disease (CKD) research field. Especially, an individual-level state transition model (microsimulation) is widely used for these researches. Some researchers set CKD grades as discrete health states, and the transition probabilities between these states were dependent on the CKD grades (disease grade-based microsimulation, MSM-dg), while others set estimated glomerular filtration rate value which determines the severity of CKD as a main variable describing patients' continuous status (kidney function-based microsimulation, MSM-kf). MSM-kf seems to reflect the real world more precisely but is more difficult to implement. We compared the calculation results of these two microsimulation models to evaluate the effect of model selection on CKD cost-effectiveness analysis. Methods: We implemented simplified MSM-dg and MSM-kf emulating natural course of CKD in general, and compared models using parameters derived from an IgA nephropathy cohort. After checking these models' overall behavior, life-years, utilities, and thresholds regarding intervention costs below which the intervention is thought as dominant (V0) or cost-effective (V1) were calculated. In addition, one-way and probabilistic sensitivity analyses were performed. Results: With base-case parameters, the calculated life-years was shorter in MSM-dg (73.89 vs. 75.80 years) while the thresholds were almost equal (86.87 vs. 90.43 (V0), 132.29 vs. 146.25 [V1 in 1000 USD]) compared to MSM-kf. Sensitivity analyses showed a tendency of the MSM-dg to show shorter results in life-years. V0 and V1 were distributed by approximately ±100,000 USD (V0) and ± 150,000 USD (V1) between models. Conclusions: Estimated cost-effectiveness thresholds by both models were not the same and its difference distributed too wide to be ignored. This result indicated that model selection in CKD cost-effectiveness research has large effect on their conclusions.

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Influence of Japan's 2004 postgraduate training on ophthalmologist location choice, supply and distribution

Sakai-Bizmark R., Goto R., Hiragi S., Tamura H.

BMC Medical Education （BMC Medical Education）  18 （ 1 ）  2018年03月

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Background: Highly-competent patient care is paramount to medicine. Quality training and patient accessibility to physicians with a wide range of specializations is essential. Yet, poor quality of life for physicians cannot be ignored, being detrimental to patient care and leading to personnel leaving the medical profession. In 2004, the Japanese government reformed postgraduate training for medical graduates, adding a 2-year, hands-on rotation through different specialties before the specialization residency was begun. Residents could now choose practice location, but it sparked concerns that physician distribution disparities had been created. Japanese media reported that residents were choosing specialties deemed to offer a higher quality of life, like Ophthalmology or Dermatology, over underserved areas like Obstetrics or Cardiology. To explore the consequences of Japan's policy efforts, through the residency reform in 2004, to improve physician training, analyzing ophthalmologist supply and distribution in the context of providing the best possible patient care and access while maintaining physician quality of life. Methods: Using secondary data, we analyzed changes in ophthalmologist supply at the secondary tier of medical care (STM). We applied ordinary least-squares regression models to ophthalmologist density to reflect community factors such as residential quality and access to further professional development, to serve as predictors of ophthalmologist supply. Coefficient equality tests examined predictor differences before and after 2004. Similar analyses were conducted for all physicians excluding ophthalmologists (other physicians). Ophthalmologist coverage in top and bottom 10% of STMs revealed supply inequalities. Results: Change in ophthalmologist supply was inversely associated with baseline ophthalmologist density before (P <.01) and after (P =.01) 2004. Changes in other physician supply were not associated with baseline other physician density before 2004 (P = 0.5), but positively associated after 2004 (P <.01). Inequalities between top and bottom 10% of ophthalmologist supply in STMs were large, with best-served areas maintaining roughly five times greater coverage than least-served areas. However, inequalities gradually declined between 1998 and 2012. Conclusions: Ophthalmologist supply increased both before and after the 2004 reform, yet contrary to media reports, proceeded at a lesser rate than supply increases for other physicians. After 2004, geographical disparities decreased for ophthalmologists, while increasing for other physicians.

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Geographical accessibility to gambling venues and pathological gambling: an econometric analysis of pachinko parlours in Japan

Kato H., Goto R.

International Gambling Studies （International Gambling Studies）  18 （ 1 ） 111 - 123 2018年01月

ISSN  14459795

　概要を見る

The relationship between geographical accessibility to gambling venues and the prevalence of pathological gambling is still unknown. This study aimed to reveal this relationship in Japan as well as its variation by subpopulation. A cross-sectional study was conducted, based on an original web-based survey to understand the level of pathological gambling depending on accessibility to pachinko parlours. Pathological gamblers were measured using the Japanese version of the South Oaks Gambling Screen. Accessibility to gambling venues was defined as the number of pachinko parlours within a 1.5 km radius from home. Moreover, the study adopted the instrumental variable approach to solve the potential endogeneity problem. The results showed that the accessibility was not significantly associated with pathological gambling in general, but that the effects of accessibility varied by subpopulation. Accessibility was significantly and positively correlated with pathological gambling for men and people in low-income areas, but this was not so for women and people in high-income areas. The study’s findings show the importance of the neighbourhood environment and could help in implementing more effective interventions for pathological gamblers.

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