Displaying publications 1 - 20 of 41 in total

  1. Kongwatcharapong J, Dilokthornsakul P, Nathisuwan S, Phrommintikul A, Chaiyakunapruk N
    Int. J. Cardiol., 2016 May 15;211:88-95.
    PMID: 26991555 DOI: 10.1016/j.ijcard.2016.02.146
    Recent studies have suggested that dipeptidyl peptidase-4 inhibitors (DPP-4 inhibitors) may be associated with increased risk of heart failure (HF), but evidence was inconclusive. We aimed to determine the effects of DPP-4 inhibitors on risk of HF.
  2. Kongpakwattana K, Dilokthornsakul P, Dhippayom T, Chaiyakunapruk N
    J Med Econ, 2020 Jul 14.
    PMID: 32580609 DOI: 10.1080/13696998.2020.1787420
    BACKGROUND: This study aimed to understand the clinical and economic burden associated with postsurgical complications in high-risk surgeries in Thailand.

    METHODS: A cost and outcome study was conducted using a retrospective cohort database from four tertiary hospitals. All patients with high-risk surgeries visiting the hospitals from 2011 to 2017 were included. Outcomes included major postsurgical complications, length of stay (LOS), in-hospital death, and total healthcare costs. Multivariate regression analyses were performed to identify risk factors of postsurgical outcomes.

    RESULTS: A total of 14,930 patients were identified with an average age of 57.7 ± 17.0 years and 34.9% being male. Gastrointestinal (GI) procedures were the most common high-risk procedures, accounting for 54.9% of the patients, followed by cardiovascular (CV) procedures (25.2%). Approximately 27.2% of the patients experienced major postsurgical complications. The top three complications were respiratory failure (14.0%), renal failure (3.5%), and myocardial infarction (3.4%). In-hospital death was 10.0%. The median LOS was 9 days. The median total costs of all included patients were 2,592 US$(IQR: 1,399-6,168 US$). The patients, who received high-risk GI surgeries and experienced major complications, had significantly increased risk of in-hospital death (OR: 4.53; 95%CI: 3.81-5.38), longer LOS (6.53 days; 95%CI: 2.60-10.46 days) and higher median total costs (2,465 US$; 95%CI: 1,945-2,984 US$), compared to those without major complications. Besides, the patients, who underwent high-risk CV surgeries and developed major complications, resulted in significantly elevated risk of in-hospital death (OR: 2.22; 95%CI: 1.74-2.84) and increased median total costs (2,719 US$; 95%CI: 2,129-3,310 US$), compared to those without major complications.

    CONCLUSIONS: Postsurgical complications are a serious problem in Thailand, as they are associated with worsening mortality risk, LOS, and healthcare costs. Clinicians should develop interventions to prevent or effectively treat postsurgical complications to mitigate such burdens.

  3. Pratoomsoot C, Sruamsiri R, Dilokthornsakul P, Chaiyakunapruk N
    PLoS ONE, 2015;10(1):e108681.
    PMID: 25633206 DOI: 10.1371/journal.pone.0108681
    Many randomised controlled trials (RCTs) of herbal interventions have been conducted in the ASEAN Communities. Good quality reporting of RCTs is essential for assessing clinical significance. Given the importance ASEAN placed on herbal medicines, the reporting quality of RCTs of herbal interventions among the ASEAN Communities deserved a special attention.
  4. Dilokthornsakul P, Sawangjit R, Inprasong C, Chunhasewee S, Rattanapan P, Thoopputra T, et al.
    J Postgrad Med, 2016 Apr-Jun;62(2):109-14.
    PMID: 27089110 DOI: 10.4103/0022-3859.180571
    Stevens-Johnson syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are life-threatening dermatologic conditions. Although, the incidence of SJS/TEN in Thailand is high, information on cost of care for SJS/TEN is limited. This study aims to estimate healthcare resource utilization and cost of SJS/TEN in Thailand, using hospital perspective.
  5. Dilokthornsakul P, Chaiyakunapruk N, Campbell JD
    J Asthma, 2017 01 02;54(1):17-23.
    PMID: 27284904 DOI: 10.1080/02770903.2016.1193601
    OBJECTIVE: To test the association of clinical evidence type, efficacy-based or effectiveness-based ("E"), versus whether or not asthma interventions' cost-effectiveness findings are favorable.

    DATA SOURCES: We conducted a systematic review of PubMed, EMBASE, Tufts CEA registry, Cochrane CENTRAL, and the UK National Health Services Economic Evaluation Database from 2009 to 2014.

    STUDY SELECTION: All cost-effectiveness studies evaluating asthma medication(s) were included. Clinical evidence type, "E," was classified as efficacy-based if the evidence was from an explanatory randomized controlled trial(s) or meta-analysis, while evidence from pragmatic trial(s) or observational study(s) was classified as effectiveness-based. We defined three times the World Health Organization cost-effectiveness willingness-to-pay (WTP) threshold or less as a favorable cost-effectiveness finding. Logistic regression tested the likelihood of favorable versus unfavorable cost-effectiveness findings against the type of "E."

    RESULTS AND CONCLUSIONS: 25 cost-effectiveness studies were included. Ten (40.0%) studies were effectiveness-based, yet 15 (60.0%) studies were efficacy-based. Of 17 studies using endpoints that could be compared to WTP threshold, 7 out of 8 (87.5%) effectiveness-based studies yielded favorable cost-effectiveness results, whereas 4 out of 9 (44.4%) efficacy-based studies yielded favorable cost-effectiveness results. The adjusted odds ratio was 15.12 (95% confidence interval; 0.59 to 388.75) for effectiveness-based versus efficacy-based achieving favorable cost-effectiveness findings. More asthma cost-effectiveness studies used efficacy-based evidence. Studies using effectiveness-based evidence trended toward being more likely to disseminate favorable cost-effective findings than those using efficacy. Health policy decision makers should pay attention to the type of clinical evidence used in cost-effectiveness studies for accurate interpretation and application.

  6. Mahlich J, Dilokthornsakul P, Sruamsiri R, Chaiyakunapruk N
    PMID: 29881328 DOI: 10.1186/s12962-018-0103-1
    Background: Health-care utilities differ considerably from country to country. Our objective was to examine the association of cultural values based on Hofstede's cultural dimensions' theory with utility values that were identified using the time trade off method.

    Methods: We performed a literature search to determine preference-based value algorithms in the general population of a given country. We then fitted a second-order quadratic function to assess the utility function curve that links health status with health-care utilities. We ranked the countries according to the concavity and convexity properties of their utility functions and compared this ranking with that of the Hofstede index to check if there were any similarities.

    Results: We identified 10 countries with an EQ-5D-5L-based value set and 7 countries with an EQ-5D-3L-based value set. Japan's degree of concavity was highest, while Germany's was lowest, based on the EQ-5D-3L and EQ-5D-5L value sets. Japan also ranked first in the Hofstede long-term orientation index, and rankings related to the degree of concavity, indicating a low time preference rate.

    Conclusions: This is the first evaluation to identify and report an association between different cultural beliefs and utility values. These findings underline the necessity to take local values into consideration when designing health technology assessment systems.

  7. Chongmelaxme B, Chaiyakunapruk N, Dilokthornsakul P
    J Med Econ, 2019 Jun;22(6):554-566.
    PMID: 30663455 DOI: 10.1080/13696998.2019.1572014
    Aims: Non-adherence is associated with poor clinical outcomes among patients with asthma. While cost-effectiveness analysis (CEA) is increasingly used to inform value assessment of the interventions, most do not take into account adherence in the analyses. This study aims to: (1) Understand the extent of studies considering adherence as part of the economic analyses, and (2) summarize the methods of incorporating adherence in the economic models. Materials and methods: A literature search was performed from the inception to February 2018 using four databases: PubMed, EMBASE, NHS EED, and the Tufts CEA registry. Decision model-based CEA of asthma were identified. Outcomes of interest were the number of studies incorporating adherence in the economic models, and the incorporating methods. All data were extracted using a standardized data collection form. Results: From 1,587 articles, 23 studies were decision model-based CEA of asthma, of which four CEA (17.4%) incorporated adherence in the analyses. Only the method of incorporating adherence by adjusting treatment effectiveness according to adherence levels was demonstrated in this review. Two approaches were used to derive the associations between adherence and effectiveness. The first approach was to apply a mathematical formula, developed by an expert panel, and the second was to extrapolate the associations from previous published studies. The adherence-adjusted effectiveness was then incorporated in the economic models. Conclusions: A very low number of CEA of asthma incorporated adherence in the analyses. All the CEA adjusted treatment effectiveness according to adherence levels, applied to the economic models.
  8. Dilokthornsakul P, Thoopputra T, Patanaprateep O, Kongsakon R, Chaiyakunapruk N
    SAGE Open Med, 2016;4:2050312116637026.
    PMID: 27026801 DOI: 10.1177/2050312116637026
    BACKGROUND: This study was conducted to determine the impacts of medication adherence on hospitalization and direct healthcare cost in patients with schizophrenia in Thailand.
    METHODS: A retrospective study was undertaken. Patients with schizophrenia aged 18-65 years who visited a University hospital and received antipsychotics from April 2011 to October 2011 were included. Propensity score-adjusted logistic regression was used to determine the impacts of medication adherence on schizophrenia-related and all-cause hospitalizations.
    RESULTS: A total of 582 patients were included. Three out of 224 patients (1.3%) were hospitalized with schizophrenia in optimal adherence group, while 10 of 140 (7.1%) were hospitalized in under-adherence group, and 7 of 218 (3.2%) were hospitalized in over-adherence group. Based on propensity score-adjusted multivariate logistic regression, the adjusted odds ratio was 5.86 (95% confidence interval = 1.53-22.50) for schizophrenia-related hospitalization and 8.04 (95% confidence interval = 2.20-29.40) for all-cause hospitalization. The average annual direct healthcare costs in patients with optimal adherence, under-adherence, and over-adherence were US$371 ± US$836, US$386 ± US$734, and US$508 ± US$2168, respectively.
    CONCLUSION: An initiation of interventions to maintain optimal adherence in patients with schizophrenia would significantly impact the healthcare system.
    KEYWORDS: Adherence; antipsychotics; cost; hospitalization
  9. Permsuwan U, Chaiyakunapruk N, Dilokthornsakul P, Thavorn K, Saokaew S
    Appl Health Econ Health Policy, 2016 Jun;14(3):281-92.
    PMID: 26961276 DOI: 10.1007/s40258-016-0228-3
    BACKGROUND: Even though Insulin glargine (IGlar) has been available and used in other countries for more than a decade, it has not been adopted into Thai national formulary. This study aimed to evaluate the long-term cost effectiveness of IGlar versus neutral protamine Hagedorn (NPH) insulin in type 2 diabetes from the perspective of Thai Health Care System.

    METHODS: A validated computer simulation model (the IMS CORE Diabetes Model) was used to estimate the long-term projection of costs and clinical outcomes. The model was populated with published characteristics of Thai patients with type 2 diabetes. Baseline risk factors were obtained from Thai cohort studies, while relative risk reduction was derived from a meta-analysis study conducted by the Canadian Agency for Drugs and Technology in Health. Only direct costs were taken into account. Costs of diabetes management and complications were obtained from hospital databases in Thailand. Both costs and outcomes were discounted at 3 % per annum and presented in US dollars in terms of 2014 dollar value. Incremental cost-effectiveness ratio (ICER) was calculated. One-way and probabilistic sensitivity analyses were also performed.

    RESULTS: IGlar is associated with a slight gain in quality-adjusted life years (0.488 QALYs), an additional life expectancy (0.677 life years), and an incremental cost of THB119,543 (US$3522.19) compared with NPH insulin. The ICERs were THB244,915/QALY (US$7216.12/QALY) and THB176,525/life-year gained (LYG) (US$5201.09/LYG). The ICER was sensitive to discount rates and IGlar cost. At the acceptable willingness to pay of THB160,000/QALY (US$4714.20/QALY), the probability that IGlar was cost effective was less than 20 %.

    CONCLUSIONS: Compared to treatment with NPH insulin, treatment with IGlar in type 2 diabetes patients who had uncontrolled blood glucose with oral anti-diabetic drugs did not represent good value for money at the acceptable threshold in Thailand.

  10. Permsuwan U, Dilokthornsakul P, Thavorn K, Saokaew S, Chaiyakunapruk N
    J Med Econ, 2017 Feb;20(2):171-181.
    PMID: 27645706 DOI: 10.1080/13696998.2016.1238386
    OBJECTIVE: With a high prevalence of chronic kidney disease (CKD) in type 2 diabetes (T2DM) in Thailand, the appropriate treatment for the patients has become a major concern. This study aimed to evaluate long-term cost-effective of dipeptidyl peptidase-4 (DPP-4) inhibitor monothearpy vs sulfonylurea (SFU) monotherapy in people with T2DM and CKD.

    METHODS: A validated IMS CORE Diabetes Model was used to estimate the long-term costs and outcomes. The efficacy parameters were identified and synthesized using a systematic review and meta-analysis. Baseline characteristics and cost parameters were obtained from published studies and hospital databases in Thailand. Costs were expressed in 2014 US Dollars. Outcomes were presented as an incremental cost-effectiveness ratio (ICER). One-way and probabilistic sensitivity analyses were performed to estimate parameter uncertainty.

    RESULTS: From a societal perspective, treatment with DPP-4 inhibitors yielded more quality-adjusted life years (QALYs) (0.024) at a higher cost (>66,000 Thai baht (THB) or >1,829.27 USD) per person than SFU, resulting in the ICER of >2.7 million THB/QALY (>74,833.70 USD/QALY). The cost-effectiveness results were mainly driven by differences in HbA1c reduction, hypoglycemic events, and drug acquisition cost of DPP-4 inhibitors. At the ceiling ratio of 160,000 THB/QALY (4,434.59 USD/QALY), the probability that DPP-4 inhibitors are cost-effective compared to SFU was less than 10%.

    CONCLUSIONS: Compared to SFU, DPP-4 inhibitor monotherapy is not a cost-effective treatment for people with T2DM and CKD in Thailand.

  11. Permsuwan U, Dilokthornsakul P, Saokaew S, Thavorn K, Chaiyakunapruk N
    Clinicoecon Outcomes Res, 2016;8:521-529.
    PMID: 27703387
    The management of type 2 diabetes mellitus (T2DM) in elderly population poses many challenges. Dipeptidyl peptidase-4 (DPP-4) inhibitors show particular promise due to excellent tolerability profiles, low risk of hypoglycemia, and little effect on body weight. This study evaluated, from the health care system's perspective, the long-term cost-effectiveness of DPP-4 inhibitor monotherapy vs metformin and sulfonylurea (SFU) monotherapy in Thai elderly T2DM patients.
  12. Dilokthornsakul P, Lee TA, Dhippayom T, Jeanpeerapong N, Chaiyakunapruk N
    Value Health Reg Issues, 2016 May;9:105-111.
    PMID: 27881251 DOI: 10.1016/j.vhri.2016.03.001
    BACKGROUND: To compare health care utilization and cost by asthma severity and type of health insurance in Thailand.

    METHODS: A retrospective cohort study using an electronic database was conducted in patients with asthma. Patients who were diagnosed with asthma from 2009 to 2011, had at least two subsequent health care encounters for asthma during the first six months after the first asthma diagnosis, and had at least 90 days of follow-up were included. The primary outcome was direct health care costs of inpatient and outpatient care. We compared outcomes between groups on the basis of a proxy of severity (mild/moderate severe asthma vs. high severe asthma) and type of health insurance using a multivariable generalized linear model. Covariates such as Patients' demographic characteristics, comorbidities, and concurrent medications were included in the model.

    RESULTS: Among 1982 patients included, the average age was 40.3 ± 24.0 years, with 60.7% being males. A total of 1936 patients had mild/moderate severe asthma, whereas 46 patients had high severe asthma. There were 1293 patients under the Universal Coverage Scheme, 264 patients under Social Security Insurance, and 626 patients under the Civil Servant Medical Benefit Scheme (CSMBS). The average annual cost per patient was $598 ± $871. In adjusted analyses, the health care cost of patients with high severe asthma was $71 higher than that of patients with mild/moderate severe asthma (95% confidence interval $-131 to $274). The cost of patients under the CSMBS was $110 (95% confidence interval $29-$191) higher than that of patients under Universal Coverage Scheme.

    CONCLUSIONS: Health care costs of patients with asthma were substantial and were higher in patients with high severe asthma and patients under the CSMBS.
  13. Permsuwan U, Thavorn K, Dilokthornsakul P, Saokaew S, Chaiyakunapruk N
    J Med Econ, 2017 Sep;20(9):991-999.
    PMID: 28649943 DOI: 10.1080/13696998.2017.1347792
    AIMS: An economic evidence is a vital tool that can inform the decision to use costly insulin analogs. This study aimed to evaluate long-term cost-effectiveness of insulin detemir (IDet) compared with insulin glargine (IGlar) in type 2 diabetes (T2DM) from the Thai payer's perspective.

    METHODS: Long-term costs and outcomes were projected using a validated IMS CORE Diabetes Model, version 8.5. Cohort characteristics, baseline risk factors, and costs of diabetes complications were derived from Thai data sources. Relative risk was derived from a systematic review and meta-analysis study. Costs and outcomes were discounted at 3% per annum. Incremental cost-effectiveness ratio (ICER) was presented in 2015 US Dollars (USD). A series of one-way and probabilistic sensitivity analyses were performed.

    RESULTS: IDet yielded slightly greater quality-adjusted life years (QALYs) (8.921 vs 8.908), but incurred higher costs than IGlar (90,417.63 USD vs 66,674.03 USD), resulting in an ICER of ∼1.7 million USD per QALY. The findings were very sensitive to the cost of IDet. With a 34% reduction in the IDet cost, treatment with IDet would become cost-effective according to the Thai threshold of 4,434.59 USD per QALY.

    CONCLUSIONS: Treatment with IDet in patients with T2DM who had uncontrolled blood glucose with oral anti-diabetic agents was not a cost-effective strategy compared with IGlar treatment in the Thai context. These findings could be generalized to other countries with a similar socioeconomics level and healthcare systems.

  14. Kongpakwattana K, Dilokthornsakul P, Dejthevaporn C, Pattanaprateep O, Chaiyakunapruk N
    J Med Econ, 2019 Jan;22(1):26-34.
    PMID: 30303420 DOI: 10.1080/13696998.2018.1534739
    Aims: Due to the lack of studies evaluating compliance or persistence with Alzheimer's Disease (AD) treatment outside High-Income Countries (HICs), this study aimed to assess compliance, persistence, and factors associated with non-compliance and non-persistence by utilizing existing "real-world" information from multiregional hospital databases in Thailand.Materials and methods: Study subjects were retrospectively identified from databases of five hospitals located in different regions across Thailand. AD patients aged ≥60 years who were newly-prescribed with donepezil, galantamine, rivastigmine, or memantine between 2013 and 2017 were eligible for analysis. The Medication Possession Ratio (MPR) was used as a proxy for compliance, while the Kaplan-Meier survival analysis was employed to estimate persistence. Logistic and Cox regressions were used to assess determinants of non-compliance and non-persistence, adjusted for age and gender.Results: Among 698 eligible patients, mean (SD) MPR was 0.83 (0.25), with 70.3% of the patients compliant to the treatment (having MPR ≥ 0.80). Half of the patients discontinued their treatment (having a treatment gap >30 days) within 177 days with a 1-year persistence probability of 21.1%. The patients treated in the university-affiliated hospital were more likely to be both non-compliant (OR = 1.71; 95% CI = 1.21-2.42) and non-persistent (HR = 1.33; 95% CI = 1.12-1.58). In addition, non-compliance was higher for those prescribed with single AD treatment (OR = 2.52; 95% CI = 1.35-4.69), while non-persistence was higher for those unable to reimburse for AD treatment (HR = 1.34; 95% CI = 1.11-1.62).Limitations: By using retrospective databases, a difficulty in validating whether the medications are actually taken after being refilled may over-estimate the levels of compliance and persistence. Meanwhile, possible random coding errors may under-estimate the strength of association findings.Conclusions: This study reveals the situation of compliance and persistence on AD treatment for the first time outside HICs. The determinants of non-compliance and non-persistence underline key areas for improvement.
  15. Chongmelaxme B, Phisalprapa P, Manthaisong R, Dilokthornsakul P, Chaiyakunapruk N
    Pharmacoeconomics, 2019 Feb;37(2):291.
    PMID: 30547370 DOI: 10.1007/s40273-018-0754-y
    Weight Reduction is Cost-Effective for the Treatment of Non-alcoholic Fatty Liver Disease in Thailand.
  16. Chongmelaxme B, Phisalprapa P, Sawangjit R, Dilokthornsakul P, Chaiyakunapruk N
    Pharmacoeconomics, 2019 02;37(2):267-278.
    PMID: 30430467 DOI: 10.1007/s40273-018-0736-0
    INTRODUCTION: This study evaluated lifetime liver-related clinical outcomes, costs of treatment, and the cost-effectiveness of treatment options for non-alcoholic fatty liver disease (NAFLD) in Thailand.

    METHODS: A cost-utility analysis using a lifetime Markov model was conducted among Thai patients with NAFLD, from a societal perspective. Pioglitazone, vitamin E, a weight reduction program, and usual care were investigated, with the outcomes of interest being the number of cirrhosis and hepatocellular carcinoma (HCC) cases, life expectancy, quality-adjusted life-years (QALYs), lifetime costs, and the incremental cost-effectiveness ratios (ICERs). One-way and probabilistic sensitivity analyses were performed.

    RESULTS: When compared with usual care, a weight reduction program can prevent cirrhosis and HCC cases by 13.91% (95% credible interval [CrI] 0.97, 20.59) and 2.12% (95% CrI 0.43, 4.56), respectively; pioglitazone can prevent cirrhosis and HCC cases by 9.30% (95% CrI -2.52, 15.24) and 1.42% (95% CrI -0.18, 3.74), respectively; and vitamin E can prevent cirrhosis and HCC cases by 7.32% (95% CrI -4.64, 15.56) and 1.12% (95% CrI -0.81, 3.44), respectively. Estimated incremental life expectancy and incremental QALYs for all treatment options compared with usual care were approximately 0.06 years and 0.07 QALYs, respectively. The lifetime costs of both a weight reduction program and pioglitazone were less than usual care, while vitamin E was $3050 (95% CrI 2354, 3650). The weight reduction program dominated all other treatment options. The probability of being cost-effective in Thailand's willingness-to-pay threshold ($4546/QALY gained) was 76% for the weight reduction program, 22% for pioglitazone, 2% for usual care, and 0% for vitamin E.

    CONCLUSIONS: A weight reduction program can prevent cirrhosis and HCC occurrences, and dominates all other treatment options. Pioglitazone and vitamin E demonstrated a trend towards decreasing the number of cirrhosis and HCC cases.

  17. Dilokthornsakul P, Chaiyakunapruk N, Jeanpeerapong N, Lee TA
    Value Health Reg Issues, 2014 May;3:222-228.
    PMID: 29702931 DOI: 10.1016/j.vhri.2014.04.013
    OBJECTIVES: To evaluate whether there are differences in propensity score (PS) and treatment effects estimated using conventional and calendar time-specific PS (CTS-PS) approaches.

    METHODS: A retrospective database analysis at a university-affiliated hospital in Thailand was used. Diabetic patients receiving glucose-lowering medications from July 2008 to June 2011 were included. Patients were categorized into those exposed and not exposed to thiazolidinediones (TZDs). PSs were estimated by using conventional PS and CTS-PS. In the CTS-PS, PS was separately estimated for three specific calendar time periods. Patients were matched 1:1 using caliper matching. The outcomes were cardiovascular and all-cause hospitalizations. The TZD and non-TZD groups were compared with Cox proportional hazard models.

    RESULTS: A total of 2165 patients were included. The average conventional PS was 0.198 (95% confidence interval [CI] 0.195-0.202), while the average PS in the CTS-PS approach was 0.212 (0.206-0.218), 0.180 (0.173-0.188), and 0.205 (0.197-0.213) for July 2008 to June 2009, July 2009 to June 2010, and July 2010 to June 2011, respectively. The average difference in PS was 0.012 (P < 0.001), -0.009 (P ≤ 0.002), and 0.000 (P = 0.950) in the three calendar time periods. The adjusted hazard ratios of the conventional PS-matched cohort were 0.97 (95% CI 0.39-2.45) and 0.97 (95% CI 0.78-1.20) for CVD-related and all-cause hospitalizations, while the adjusted hazard ratios of the CTS-PS-matched cohort were 1.11 (95% CI 0.43-2.88) and 1.12 (95% CI 0.91-1.39), respectively.

    CONCLUSION: CTS-PS is different from PS estimated by using the conventional approach. CTS-PS should be considered when a pattern of medication use has changed over the study period.

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