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Published in: BMC Health Services Research 1/2023

Open Access 01-12-2023 | Research article

Comparison of diagnosis-based risk adjustment methods for episode-based costs to apply in efficiency measurement

Authors: Juyoung Kim, Minsu Ock, In-Hwan Oh, Min-Woo Jo, Yoon Kim, Moo-Song Lee, Sang-il Lee

Published in: BMC Health Services Research | Issue 1/2023

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Abstract

Background

The recent rising health spending intrigued efficiency and cost-based performance measures. However, mortality risk adjustment methods are still under consideration in cost estimation, though methods specific to cost estimate have been developed. Therefore, we aimed to compare the performance of diagnosis-based risk adjustment methods based on the episode-based cost to utilize in efficiency measurement.

Methods

We used the Health Insurance Review and Assessment Service–National Patient Sample as the data source. A separate linear regression model was constructed within each Major Diagnostic Category (MDC). Individual models included explanatory (demographics, insurance type, institutional type, Adjacent Diagnosis Related Group [ADRG], diagnosis-based risk adjustment methods) and response variables (episode-based costs). The following risk adjustment methods were used: Refined Diagnosis Related Group (RDRG), Charlson Comorbidity Index (CCI), National Health Insurance Service Hierarchical Condition Categories (NHIS-HCC), and Department of Health and Human Service-HCC (HHS-HCC). The model accuracy was compared using R-squared (R2), mean absolute error, and predictive ratio. For external validity, we used the 2017 dataset.

Results

The model including RDRG improved the mean adjusted R2 from 40.8% to 45.8% compared to the adjacent DRG. RDRG was inferior to both HCCs (RDRG adjusted R2 45.8%, NHIS-HCC adjusted R2 46.3%, HHS-HCC adjusted R2 45.9%) but superior to CCI (adjusted R2 42.7%). Model performance varied depending on the MDC groups. While both HCCs had the highest explanatory power in 12 MDCs, including MDC P (Newborns), RDRG showed the highest adjusted R2 in 6 MDCs, such as MDC O (pregnancy, childbirth, and puerperium). The overall mean absolute errors were the lowest in the model with RDRG ($1,099). The predictive ratios showed similar patterns among the models regardless of the  subgroups according to age, sex, insurance type, institutional type, and the upper and lower 10th percentiles of actual costs. External validity also showed a similar pattern in the model performance.

Conclusions

Our research showed that either NHIS-HCC or HHS-HCC can be useful in adjusting comorbidities for episode-based costs in the process of efficiency measurement.
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Literature
2.
go back to reference OECD. Health at a Glance 2019. Paris (FR), OECD Publishing. 2019. Accessed 26 December 2022. OECD. Health at a Glance 2019. Paris (FR), OECD Publishing. 2019. Accessed 26 December 2022.
3.
go back to reference Wagstaff A, Flores G, Hsu J, Smitz MF, Chepynoga K, Buisman LR, et al. Progress on catastrophic health spending in 133 countries: a retrospective observational study. Lancet Glob Health. 2018;6:e169–79.CrossRefPubMed Wagstaff A, Flores G, Hsu J, Smitz MF, Chepynoga K, Buisman LR, et al. Progress on catastrophic health spending in 133 countries: a retrospective observational study. Lancet Glob Health. 2018;6:e169–79.CrossRefPubMed
6.
go back to reference Kwon S, M. Advancing universal health coverage : what developing countries can learn from the Korean experience? Universal Health Coverage Studies Series Vol.33. Washington, DC, World Bank. 2018 http://hdl.handle.net/10986/29179. Accessed 7 July 2022. Kwon S, M. Advancing universal health coverage : what developing countries can learn from the Korean experience? Universal Health Coverage Studies Series Vol.33. Washington, DC, World Bank. 2018 http://​hdl.​handle.​net/​10986/​29179. Accessed 7 July 2022.
7.
go back to reference Hussey PS, de Vries H, Romley J, Wang MC, Chen SS, Shekelle PG, et al. A systematic review of health care efficiency measures. Health Serv Res. 2009;44:784–805.CrossRefPubMedPubMedCentral Hussey PS, de Vries H, Romley J, Wang MC, Chen SS, Shekelle PG, et al. A systematic review of health care efficiency measures. Health Serv Res. 2009;44:784–805.CrossRefPubMedPubMedCentral
8.
go back to reference Zhang F, Wong C, Chiu Y, Ensor J, Mohamed MO, Peat G, et al. Prognostic impact of comorbidity measures on outcomes following acute coronary syndrome: a systematic review. Int J Clin Pract. 2021;75:e14345.CrossRefPubMed Zhang F, Wong C, Chiu Y, Ensor J, Mohamed MO, Peat G, et al. Prognostic impact of comorbidity measures on outcomes following acute coronary syndrome: a systematic review. Int J Clin Pract. 2021;75:e14345.CrossRefPubMed
9.
go back to reference Gundtoft PH, Jørstad M, Erichsen JL, Schmal H, Viberg B. The ability of comorbidity indices to predict mortality in an orthopedic setting: a systematic review. Syst Rev. 2021;10:234.CrossRefPubMedPubMedCentral Gundtoft PH, Jørstad M, Erichsen JL, Schmal H, Viberg B. The ability of comorbidity indices to predict mortality in an orthopedic setting: a systematic review. Syst Rev. 2021;10:234.CrossRefPubMedPubMedCentral
10.
go back to reference Maciejewski ML, Liu CF, Fihn SD. Performance of comorbidity, risk adjustment, and functional status measures in expenditure prediction for patients with diabetes. Diabetes Care. 2009;32:75–80.CrossRefPubMedPubMedCentral Maciejewski ML, Liu CF, Fihn SD. Performance of comorbidity, risk adjustment, and functional status measures in expenditure prediction for patients with diabetes. Diabetes Care. 2009;32:75–80.CrossRefPubMedPubMedCentral
11.
go back to reference Iezzoni LI. Risk adjustment for measuring health care outcomes: AUPHA; 2013. Iezzoni LI. Risk adjustment for measuring health care outcomes: AUPHA; 2013.
12.
go back to reference Centers for Medicare & Medicaid Services (CMS). Merit-Based Incentive Payment System (MIPS): Medicare Spending Per Beneficiary (MSPB) clinician measure. Measure information form-2021 performance period. Baltimore, MD, Centers for Medicare & Medicaid Services (CMS). 2020 https://qpp.cms.gov/docs/cost_ specifications/2020–12–14-mif-mspb-clinician.pdf. Accessed 7 July 2022. Centers for Medicare & Medicaid Services (CMS). Merit-Based Incentive Payment System (MIPS): Medicare Spending Per Beneficiary (MSPB) clinician measure. Measure information form-2021 performance period. Baltimore, MD, Centers for Medicare & Medicaid Services (CMS). 2020 https://​qpp.​cms.​gov/​docs/​cost_​ specifications/2020–12–14-mif-mspb-clinician.pdf. Accessed 7 July 2022.
14.
go back to reference Kautter J, Pope GC, Ingber M, Freeman S, Patterson L, Cohen M, et al. The HHS4HCC risk adjustment model for individual and small group markets under the Affordable Care Act. Medicare Medicaid Res Rev. 2014;4:mmrr2014–004–03-a03. Kautter J, Pope GC, Ingber M, Freeman S, Patterson L, Cohen M, et al. The HHS4HCC risk adjustment model for individual and small group markets under the Affordable Care Act. Medicare Medicaid Res Rev. 2014;4:mmrr2014–004–03-a03.
15.
go back to reference Han KM, Ryu MK, Chun KH. Prediction of health care cost using the hierarchical condition category risk adjustment model. Korean Academy of Health Policy and Management. 2017;27:149–56. Han KM, Ryu MK, Chun KH. Prediction of health care cost using the hierarchical condition category risk adjustment model. Korean Academy of Health Policy and Management. 2017;27:149–56.
16.
go back to reference Lee SH, Cho KH, Choi YE, Park SB, Park YM, Choi JH, et al. Prediction of health care cost using the NHIS-HCC risk adjustment model and mortality analysis. Goyang (KR): National Health Insurance Service Ilsan Hospital; 2020. Lee SH, Cho KH, Choi YE, Park SB, Park YM, Choi JH, et al. Prediction of health care cost using the NHIS-HCC risk adjustment model and mortality analysis. Goyang (KR): National Health Insurance Service Ilsan Hospital; 2020.
17.
go back to reference Kim Y, Jo MW, Ock MS, Kim JY, Song JH. Research on reform of current healthcare quality evaluation system. Seoul National University. 2020 https://www.archives.go. kr/next/manager/publishmentSubscriptionDetail.do?prt_seq=139455&page=4&prt_arc_title=&prt_pub_kikwan=&prt_no=. Accessed 18 August 2022. Kim Y, Jo MW, Ock MS, Kim JY, Song JH. Research on reform of current healthcare quality evaluation system. Seoul National University. 2020 https://​www.​archives.​go. kr/next/manager/publishmentSubscriptionDetail.do?prt_seq=139455&page=4&prt_arc_title=&prt_pub_kikwan=&prt_no=. Accessed 18 August 2022.
18.
go back to reference Pope GC, Kautter J, Ellis RP, Ash AS, Ayanian JZ, Lezzoni LI, et al. Risk adjustment of Medicare capitation payments using the CMS-HCC model. Health Care Financ Rev. 2004;25:119–41.PubMedPubMedCentral Pope GC, Kautter J, Ellis RP, Ash AS, Ayanian JZ, Lezzoni LI, et al. Risk adjustment of Medicare capitation payments using the CMS-HCC model. Health Care Financ Rev. 2004;25:119–41.PubMedPubMedCentral
21.
go back to reference Kim L, Kim JA, Kim S. A guide for the utilization of Health Insurance Review and Assessment Service National Patient Samples. Epidemiol Health. 2014;36:e2014008.CrossRefPubMedPubMedCentral Kim L, Kim JA, Kim S. A guide for the utilization of Health Insurance Review and Assessment Service National Patient Samples. Epidemiol Health. 2014;36:e2014008.CrossRefPubMedPubMedCentral
22.
go back to reference Lee C, Kim JM, Kim Y-S, Shin E. the effect of diagnosis-related groups on the shift of medical services from inpatient to outpatient settings: a national claims-based analysis. Asia Pacific Journal of Public Health. 2019;31:499–509.CrossRefPubMed Lee C, Kim JM, Kim Y-S, Shin E. the effect of diagnosis-related groups on the shift of medical services from inpatient to outpatient settings: a national claims-based analysis. Asia Pacific Journal of Public Health. 2019;31:499–509.CrossRefPubMed
23.
go back to reference Health Insurance Review & Assessment Service (HIRA). KDRG Version 4.2. Wonju, Gangwondo (KR), Health Insurance Review & Assessment Service. 2018. Accessed 26 Dec 2022. Health Insurance Review & Assessment Service (HIRA). KDRG Version 4.2. Wonju, Gangwondo (KR), Health Insurance Review & Assessment Service. 2018. Accessed 26 Dec 2022.
25.
go back to reference Ellis RP, Hsu HE, Siracuse JJ, Walkey AJ, Lasser KE, Jacobson BC, et al. Development and Assessment of a New Framework for Disease Surveillance, Prediction, and Risk Adjustment: The Diagnostic Items Classification System. JAMA Health Forum. 2022;3:e220276.CrossRefPubMedPubMedCentral Ellis RP, Hsu HE, Siracuse JJ, Walkey AJ, Lasser KE, Jacobson BC, et al. Development and Assessment of a New Framework for Disease Surveillance, Prediction, and Risk Adjustment: The Diagnostic Items Classification System. JAMA Health Forum. 2022;3:e220276.CrossRefPubMedPubMedCentral
26.
go back to reference CMS. Merit-Based Incentive Payment System (MIPS): Medicare Spending Per Beneficiary (MSPB) Clinician Measure. In: Measure Information Form 2023 Performance Period. Centers for Medicare & Medicaid Services; 2022. CMS. Merit-Based Incentive Payment System (MIPS): Medicare Spending Per Beneficiary (MSPB) Clinician Measure. In: Measure Information Form 2023 Performance Period. Centers for Medicare & Medicaid Services; 2022.
27.
go back to reference Sandhu AT, Do R, Lam J, Blankenship J, Van Decker W, Rich J, et al. Development of the Elective Outpatient Percutaneous Coronary Intervention Episode-Based Cost Measure. Circ Cardiovasc Qual Outcomes. 2021;14:e006461.CrossRefPubMed Sandhu AT, Do R, Lam J, Blankenship J, Van Decker W, Rich J, et al. Development of the Elective Outpatient Percutaneous Coronary Intervention Episode-Based Cost Measure. Circ Cardiovasc Qual Outcomes. 2021;14:e006461.CrossRefPubMed
28.
go back to reference Harrell FE. Regression modeling strategies: with applications to linear models, logistic and ordinal regression, and survival analysis. Cham (CH): Springer; 2015.CrossRef Harrell FE. Regression modeling strategies: with applications to linear models, logistic and ordinal regression, and survival analysis. Cham (CH): Springer; 2015.CrossRef
31.
go back to reference Charlson ME, Charlson RE, Peterson JC, Marinopoulos SS, Briggs WM, Hollenberg JP. The Charlson comorbidity index is adapted to predict costs of chronic disease in primary care patients. J Clin Epidemiol. 2008;61:1234–40.CrossRefPubMed Charlson ME, Charlson RE, Peterson JC, Marinopoulos SS, Briggs WM, Hollenberg JP. The Charlson comorbidity index is adapted to predict costs of chronic disease in primary care patients. J Clin Epidemiol. 2008;61:1234–40.CrossRefPubMed
32.
go back to reference Kim KH. Comorbidity adjustment in health insurance claim database. Health Policy and Mangemnet. 2016;26:71–8.CrossRef Kim KH. Comorbidity adjustment in health insurance claim database. Health Policy and Mangemnet. 2016;26:71–8.CrossRef
34.
go back to reference Duncan IG. Healthcare risk adjustment and predictive modeling. New Hartford, Conn.: ACTEX Publications; 2018. Duncan IG. Healthcare risk adjustment and predictive modeling. New Hartford, Conn.: ACTEX Publications; 2018.
35.
36.
go back to reference Jian W, Lu M, Han W, Hu M. Introducing diagnosis-related groups: is the information system ready? Int J Health Plann Manage. 2016;31:E58-68.CrossRefPubMed Jian W, Lu M, Han W, Hu M. Introducing diagnosis-related groups: is the information system ready? Int J Health Plann Manage. 2016;31:E58-68.CrossRefPubMed
37.
go back to reference Bell BA, Ene M, Smiley W, Schoeneberger JA. A multilevel model primer using SAS PROC MIXED. In: SAS Glob Forum: 2013: University of South Carolina Columbia, SC, USA; 2013: 1–19. Bell BA, Ene M, Smiley W, Schoeneberger JA. A multilevel model primer using SAS PROC MIXED. In: SAS Glob Forum: 2013: University of South Carolina Columbia, SC, USA; 2013: 1–19.
38.
go back to reference Candlish J, Teare MD, Dimairo M, Flight L, Mandefield L, Walters SJ. Appropriate statistical methods for analysing partially nested randomised controlled trials with continuous outcomes: a simulation study. BMC Med Res Methodol. 2018;18:105.CrossRefPubMedPubMedCentral Candlish J, Teare MD, Dimairo M, Flight L, Mandefield L, Walters SJ. Appropriate statistical methods for analysing partially nested randomised controlled trials with continuous outcomes: a simulation study. BMC Med Res Methodol. 2018;18:105.CrossRefPubMedPubMedCentral
39.
go back to reference Ene M, Smiley W, Bell BA. MIXED_FIT: A SAS® macro to assess model fit and adequacy for two-level linear models. In: SAS Global Forum 2013: 2013: Citeseer; 2013. Ene M, Smiley W, Bell BA. MIXED_FIT: A SAS® macro to assess model fit and adequacy for two-level linear models. In: SAS Global Forum 2013: 2013: Citeseer; 2013.
40.
go back to reference Kim S, Jung C, Yon J, Park H, Yang H, Kang H, et al. A review of the complexity adjustment in the Korean Diagnosis-Related Group (KDRG). Health Inf Manag. 2020;49:62–8.PubMed Kim S, Jung C, Yon J, Park H, Yang H, Kang H, et al. A review of the complexity adjustment in the Korean Diagnosis-Related Group (KDRG). Health Inf Manag. 2020;49:62–8.PubMed
44.
go back to reference Kim J, Choi EY, Lee W, Oh HM, Pyo J, Ock M, et al. Feasibility of capturing adverse events from insurance claims data using international classification of diseases, tenth revision, codes coupled to present on admission indicators. J Patient Saf. 2022;18:404–9.CrossRefPubMed Kim J, Choi EY, Lee W, Oh HM, Pyo J, Ock M, et al. Feasibility of capturing adverse events from insurance claims data using international classification of diseases, tenth revision, codes coupled to present on admission indicators. J Patient Saf. 2022;18:404–9.CrossRefPubMed
45.
go back to reference U.S. Department of Health & Human Services (HHS). International Classification of Disease, (ICD-10-CM/PCS) Transition - background. Washington, DC, U.S. Department of Health & Human Services (HHS). 2015 https://www.cdc.gov/nchs /icd/icd10cm_pcs_background.htm. Accessed 5 July 2022. U.S. Department of Health & Human Services (HHS). International Classification of Disease, (ICD-10-CM/PCS) Transition - background. Washington, DC, U.S. Department of Health & Human Services (HHS). 2015 https://​www.​cdc.​gov/​nchs /icd/icd10cm_pcs_background.htm. Accessed 5 July 2022.
47.
go back to reference van Kleef RC, McGuire TG, van Vliet R, van de Ven W. Improving risk equalization with constrained regression. Eur J Health Econ. 2017;18:1137–56.CrossRefPubMed van Kleef RC, McGuire TG, van Vliet R, van de Ven W. Improving risk equalization with constrained regression. Eur J Health Econ. 2017;18:1137–56.CrossRefPubMed
48.
go back to reference Pagano E, Petrelli A, Picariello R, Merletti F, Gnavi R, Bruno G. Is the choice of the statistical model relevant in the cost estimation of patients with chronic diseases? An empirical approach by the Piedmont Diabetes Registry. BMC Health Serv Res. 2015;15:582.CrossRefPubMedPubMedCentral Pagano E, Petrelli A, Picariello R, Merletti F, Gnavi R, Bruno G. Is the choice of the statistical model relevant in the cost estimation of patients with chronic diseases? An empirical approach by the Piedmont Diabetes Registry. BMC Health Serv Res. 2015;15:582.CrossRefPubMedPubMedCentral
49.
go back to reference Choi J-I. National health insurance system of Korea: resource-based relative value scale and a new healthcare policy. Taehan Yongsang Uihakhoe chi. 2020;81:1024–37.PubMed Choi J-I. National health insurance system of Korea: resource-based relative value scale and a new healthcare policy. Taehan Yongsang Uihakhoe chi. 2020;81:1024–37.PubMed
Metadata
Title
Comparison of diagnosis-based risk adjustment methods for episode-based costs to apply in efficiency measurement
Authors
Juyoung Kim
Minsu Ock
In-Hwan Oh
Min-Woo Jo
Yoon Kim
Moo-Song Lee
Sang-il Lee
Publication date
01-12-2023
Publisher
BioMed Central
Published in
BMC Health Services Research / Issue 1/2023
Electronic ISSN: 1472-6963
DOI
https://doi.org/10.1186/s12913-023-10282-4

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