Assessment of Validity of Inpatient Classification System in Korean Medicine (KDRG-KM)

Article information

J Korean Med. 2016;37(3):112-122
Publication date (electronic) : 2016 September 30
doi : https://doi.org/10.13048/jkm.16039
1KM Standards Center, Korea Institute of Oriental Medicine
2Research Institute for Korean Medicine, Pusan National University
3College of Korean Medicine, Dongguk University
4Division of Humanities and Social Medicine, School of Korean Medicine, Pusan National University
Correspondence to: 임병묵 (Byungmook Lim), 부산대학교 한의학전문대학원 인문사회의학부, Tel: +82-51-510-8453, Fax: +82-51-510-8446, E-mail: limb@pusan.ac.kr
*

공동 제1저자로서 동등하게 기여하였음.

Received 2016 August 21; Revised 2016 September 29; Accepted 2016 September 29.

Abstract

Objectives

This study aimed to assess the validity of ‘Korean Diagnosis Related Groups-Korean Medicine (KDRG-KM)’which was developed by Health Insurance Review & Assessment Service (HIRA) in 2013

Methods

Among inpatient EDI claim data issued by hospitals and clinics in 2012, the data which included Korean medicine procedures were selected and analyzed. We selected control targets in the Korean medicine hospitals which had longer Episodes-Costliness index (ECI) and Lengthiness index (LI) than average of total Korean medicine hospitals, and compared the results of selection between the major diagnosis-based patient classification system and the KDRG-KM system. Finally, the explanation power (R2) and coefficient of variation (CV) of the KDRG-KM system using practice expenses were calculated.

Results

The numbers of control target in Korean medicine hospitals changed from 36 to 32 when patient grouping adjustment method was changed from major diagnosis to KDRG-KM. For expenses of all outpatient claim data on Korean medicine, explanation power of KDRG-KM system was 66.48% after excluding outliers. CVs of expenses of patient groups in Korean medicine hospitals were gathered from under 70% to under 90%, and those in long-term care hospitals mostly belonged under 70%.

Conclusions

The validity of KDRG-KM system was assured in terms of explanation power. By adapting KDRG-KM system, fairness of control targets selection for costliness management in Korean medicine hospitals can be enhanced.

Fig. 1

KDRG-KM Classification Flow

* Genuine KM Admission: Korean Medicine (KM) hospital admission except Co-treatment admission, Co-treatment Admission: KM treatment claim during Western Medicine hospital admission

** 5 disease groups: ‘Diseases of the blood and blood-forming organs’, ‘Pregnancy, childbirth, congenital malformations’, ‘health status and contact with health services’, ‘KM disease of external contraction’, ‘KM Sasang Constitutional disease’

Fig. 2

Calculation of ECI(Episodes-Costliness Index)

Fig. 3

Calculation of LI(Lengthiness Index)

Fig. 4

Calculation of Explanatory Power(R2) for Expense Variation

Fig. 5

Calculation of Coefficient of Variation (CV) for Medical Expenses

KDRG-KM Disease Groups

Classification of KDRG-KM Procedure Groups

No. of Object Hospitals before and after Applying KDRG-KM

KM Hospitals which were Transposed as Applying KDRG-KM

Lengths of Stay of Typical KM Hospitals which were transposed (unit: case, %)

Explanatory Power(R2) of KDRG-KM for Medical Expense (unit: case, %)

No. of KDRG-KM Groups by CV of Medical Expense

Lengths of Stay of Frequent KDRG-KM Patients Groups and Major Diagnostic Groups in A1 and A8 Hospitals (unit: day, case)

Lengths of Stay of Frequent KDRG-KM Patients Groups and Major Diagnostic Groups in B1 and B3 Hospitals (unit: day, case)

References

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2. Health insurance review & assessment service. KOPG-OM classification book 2011.
3. Health insurance review & assessment service. Classification process of Korean medicine patient classification system. In : Meeting materials for 2016 1st Korean medicine patient classification system review committee; 2016.
4. Health insurance review & assessment service. Korean medicine hospital EDI claims data file 2012.
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6. Thomas JW, Ashcraft MLF. Measuring severity of illness: Case severity systems and their ability to explain cost variations. Inquiry 1991;28:39–55.
7. Averill RF, Muldoon JH, Vertrees JC, Goldfield NI, et al. The evolution of casemix measurement using DRGs. 3M HIS Sorking Paper 1997. p. 5–98.
8. Palmer G, Reid B. Evaluation of the performance of diagnosis-related groups and similar casemix systems: methodoldgical issues. Health services Management Research 2001;14:71–81.
9. Kim HS, Lee SH, Nam JM. Evaluation of the homogeneity of Korean diagnosis related groups. Health Policy and Management 2013;23(1):44–51.
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Article information Continued

Fig. 1

KDRG-KM Classification Flow

* Genuine KM Admission: Korean Medicine (KM) hospital admission except Co-treatment admission, Co-treatment Admission: KM treatment claim during Western Medicine hospital admission

** 5 disease groups: ‘Diseases of the blood and blood-forming organs’, ‘Pregnancy, childbirth, congenital malformations’, ‘health status and contact with health services’, ‘KM disease of external contraction’, ‘KM Sasang Constitutional disease’

Fig. 2

Calculation of ECI(Episodes-Costliness Index)

Fig. 3

Calculation of LI(Lengthiness Index)

Fig. 4

Calculation of Explanatory Power(R2) for Expense Variation

Fig. 5

Calculation of Coefficient of Variation (CV) for Medical Expenses

Table 1

KDRG-KM Disease Groups

No. Code KDRG-KM disease group name
1 A00–B99, U206, U273, U284, U289 Certain infectious and parasitic diseases (특정 감염성 및 기생충성 질환)
2 C00–D09 Malignant neoplasms (악성 신생물)
3 D10–D48, U297 Benign neoplasm (양성 신생물)
4 D50–D89 Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (혈액및 조혈기관의 질환과 면역기전을 침범하는 특정장애)
5 E00–E90, U200 Endocrine, nutritional and metabolic disease (내분비, 영양 및 대사 질환)
6 F00–F03 Dementia (치매)
7 F04–F99, U204, U207, U220–2, U255, U275, U334–5 Mental and behavioral disorders except dementia (치매 외 정신 및 행동 장애)
8 G00–G99, U205, U230–1, U233, U236, U238–9, U333, U336, U338 Diseases of the nervous system (신경계통의 질환)
9 H00–H95, U250–3 Disease of eye and ear (눈 및 귀의 질환)
10 I00–I52, I70–I99 Disease of the circulatory system except cerebrovascular disease (뇌혈관질환 외 순환기계통의 질환)
11 I60–I69, U234 Cerebrovascular disease (뇌혈관질환)
12 J00–J22, U254 Diseases of the acute respiratory system (급성 호흡기계통의 질환)
13 J30–J99 Diseases of the chronic respiratory system (만성 호흡기계통의 질환)
14 K00–K93, U280, U288, U331 Diseases of the digestive system (소화기계통의 질환)
15 L00–L99, U290–6 Diseases of the skin and subcutaneous tissue (피부 및 피하조직의 질환)
16 M00–M36, U300–5 Diseases of the joint and connective tissue (관절 및 결합조직장애)
17 M40–M54 Dorsopathies and Spondylopathies (등 및 척추병증)
18 M60–M99 Other disorders of the musculoskeletal system and connective tissue (근골결합조직 기타장애)
19 N00–N99, U313–23 Diseases of The genitoruinary system (비뇨생식기계통의 질환)
20 O00–Q99, U324–7, U330 Pregnancy, childbirth, congenital malformations, deformations, and chromosomal abnormalities (임신, 출산, 출생, 선천 기형, 변형 및염색체이상)
21 R00–R99, U208–9, U232, U235, U237, U240–1, U260–3, U270–2, U274, U276, U281–3, U285–7, U306, U310–2, U332, U337 Symptoms, signs and abnormal clinical and laboratory findings, NEC (달리 분류되지 않은 증상, 징후와 임상 및 검사의 이상소견)
22 S00–S99 Injuries of musculoskeletal system (근골격계 손상)
23 T00–T98, U203 Injury, poisoning and certain other consequences of external causes (손상, 중독 및 외인에 의한 특정 기타 결과)
24 Z00–Z99, U00~19, U277 Factors influencing health status and contact with health servisces (건강상태 및 보건서비스 접촉에 영향을 주는 요인
25 U50–U59 KM disease of external contraction (한의외감병증)
26 U60–U79, U210–1, U201–2 KM Qi, blood, viscera and bowels disease (한의기혈장부병증 및 기타한의병명)
27 U95–U98 KM Sasang Constitutional disease (한의사상체질병증)

Table 2

Classification of KDRG-KM Procedure Groups

Procedure group name Definition
Simple group In this group, claims contain one of acupuncture, moxibustion, cupping, or physical therapy and do not belong to defined procedure groups. (침, 구, 부항, 물리치료를 시술하였으나, 정의된 시술그룹에 해당되지 않은 경우)
Acupuncture-Moxibustion group In this group, each claim contains acupuncture and moxibustion all together. (침술과 구가 병용된 조합)
Acupuncture-Cupping group In this group, each claim contains acupuncture and cupping all together. (침술과 부항이 병용된 조합)
Acupuncture-Moxibustion-Cupping group In this group, each claim contains acupuncture, moxibustion, and cupping all together. (침술, 구, 부항이 병용된 조합)
Consolidation group All disease-procedure group which has less than 100 claims is consolidated into this group. (건수가100건 미만인 상병-시술그룹을 통합한 군)

Table 3

No. of Object Hospitals before and after Applying KDRG-KM

No. of hospitals with ECI≧1.0 & LI≧1.1 & in the top 15%
Before applying KDRG-KM (major diagnosis was used) 110 71 36
After applying KDRG-KM 112 76 32

Table 4

KM Hospitals which were Transposed as Applying KDRG-KM

Hospital code LI before applying KDRG-KM LI after applying KDRG-KM Total length of stay
Index down hospitals (Hospitals that came out of costliness management object) A1 1.341 1.219 749
A2 1.261 1.207 4,186
A3 1.264 1.207 5,412
A4 1.270 1.210 12,632
A5 1.262 1.234 7,274
A6 1.257 1.219 8,708
A7 1.276 1.225 7,016
A8 1.264 1.180 14,740
A9 1.270 1.243 9,772
A10 1.269 1.219 7,736
A11 1.265 1.149 3,517
A12 1.312 1.241 2,687
A13 1.275 1.194 6,979
Index up hospitals (Hospitals that came into costliness management object) B1 1.007 1.428 8,588
B2 1.175 1.317 568
B3 1.067 1.275 5,798
B4 1.197 1.278 1,700
B5 1.232 1.379 4,662
B6 1.198 1.267 6,310
B7 1.220 1.298 15,389
B8 1.243 1.312 3,148
B9 1.135 1.290 421

Table 5

Lengths of Stay of Typical KM Hospitals which were transposed (unit: case, %)

Index down hospitals (지표하향기관) Index up hospitals (지표 상향기관) Total
A1 A8 B1 B3
0~5 n 2 68 40 122 232
% 3.77 6.3 6.32 23.11 10.12
~11 n 13 130 72 172 387
% 24.53 12.05 11.37 32.58 16.88
~15 n 15 662 450 104 1,231
% 28.3 61.35 71.09 19.70 53.69
16~ n 23 219 71 130 443
% 43.4 20.3 11.22 24.62 19.32
Total n 53 1,079 633 528 2,293
% 100 100 100 100 100

Table 6

Explanatory Power(R2) of KDRG-KM for Medical Expense (unit: case, %)

Total No. of cases No. of outliers (% of total cases) No. of analyzed R2 F p-value
Before excluding outliers 943,842 5(0.01) 943,837 57.41 5481.72 <.0001
After excluding outliers 943,842 35,987(3.81) 907,855 66.48 7757.95 <.0001

Table 7

No. of KDRG-KM Groups by CV of Medical Expense

CV Genuine KM hospital admission Co-practice admission
~40 0 2
~50 0 14
~60 16 43
~70 20 20
~80 24 11
~90 25 4
~100 18 2
>100 6 2
Total 109 98

Table 8

Lengths of Stay of Frequent KDRG-KM Patients Groups and Major Diagnostic Groups in A1 and A8 Hospitals (unit: day, case)

Hospitals Adjustment measure Code* Frequency Mean of length of stay of object hospital (A) Mean of length of stay of total KM institutions (B) (A)/(B)
A1 KDRG-KM patients groups Q0521 16 12.81 12.23 1.05
V0520 15 14.53 10.76 1.35
V0541 9 14.89 10.94 1.36
P0521 5 18 11.66 1.54
Major diagnostic groups S3350 14 14.64 10.55 1.39
M5456 6 12 10.65 1.13
S134 5 13.2 9.98 1.32
A8 KDRG-KM patients groups Q0521 505 14.37 12.23 1.18
V0520 398 12.75 10.76 1.19
P0521 69 14.07 11.66 1.21
R0520 66 13.53 11.08 1.22
Q0511 5 17.80 9.72 1.83
Major diagnostic group S3350 225 13.00 10.55 1.23
M5456 212 13.67 10.65 1.28
M511 51 16.65 11.54 1.44
*

Disease codes in KDRG-KM groups of this table were made for convenience sake and different with actual KDRG-KM disease codes.

Table 9

Lengths of Stay of Frequent KDRG-KM Patients Groups and Major Diagnostic Groups in B1 and B3 Hospitals (unit: day, case)

Hospitals Adjustment measure Code* Frequency Mean of length of stay of object hospital (A) Mean of length of stay of total KM institutions (B) (A)/(B)
B1 KDRG-KM patients groups U0511 593 13.64 9.55 1.43
U0530 11 14.55 7.95 1.83
N0510 9 11.89 6.75 1.76
B0510 6 13.17 8.70 1.51
H0510 5 9.00 8.35 1.08
Major diagnostic groups R1012 588 13.71 13.63 1.01
R51 18 13.06 7.85 1.66
G478 5 9.00 5.64 1.59
B3 KDRG-KM patients groups Q0511 112 12.99 9.72 1.34
V0510 71 11.04 9.00 1.23
Q0531 58 14.17 11.78 1.20
Major diagnostic groups M4727 33 13.33 11.86 1.12
M501 25 11.64 11.48 1.01
M5450 17 9.88 11.54 0.86
S337 17 8.41 10.70 0.79
M5446 16 14.01 10.87 1.29
*

Disease codes in KDRG-KM groups of this table were made for convenience sake and different with actual KDRG-KM disease codes.