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

Dongsu Kim; Jiseon Ryu; Byungwook Lee; Byungmook Lim; Kim, Dongsu; Ryu, Jiseon; Lee, Byungwook; Lim, Byungmook

doi:10.13048/jkm.16039

JKM > Volume 37(3); 2016 > Article

Kim, Ryu, Lee, and Lim: Assessment of Validity of Inpatient Classification System in Korean Medicine (KDRG-KM)

Original Article

The Journal of Korean Medicine 2016; 37(3): 112-122.

Published online: September 30, 2016

DOI: https://doi.org/10.13048/jkm.16039

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

Dongsu Kim¹^{, *}, Jiseon Ryu²^{, *}, Byungwook Lee³, Byungmook Lim⁴

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 August 21, 2016 Revised September 29, 2016 Accepted September 29, 2016

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.

Keywords: Patient classification system, Diagnosis related groups, Korean Medicine, explanation power, Costliness index, Lengthiness index

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	Total
0~5	n	2	68	40	122	232
0~5	%	3.77	6.3	6.32	23.11	10.12
~11	n	13	130	72	172	387
~11	%	24.53	12.05	11.37	32.58	16.88
~15	n	15	662	450	104	1,231
~15	%	28.3	61.35	71.09	19.70	53.69
16~	n	23	219	71	130	443
16~	%	43.4	20.3	11.22	24.62	19.32
Total	n	53	1,079	633	528	2,293
Total	%	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.

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