1999 diag-nosis related group; DRGs
1998 2002
12,737,642
DRGs 1998
case mix index; CMI 14
generalized estimating equation; GEE
1998 CMI 14 1999 1999 CMI 2000 1999 14 DRGs
1983
diagnosis related groups, DRGs prospective payment system, PPS
Medicare
Fetter, Shin, Freeman, Averill, & Thompson, 1980; Fetter & Free-man, 1986; Feinglass & Holloway, 1991; Coulam & Gaumer, 1991; Guterman, Eggers, Riley, Greene, & Terrell, 1988
DRGs
case
mix index, CMI Fetter, 1984;
Feinglass et al., 1991; Guterman et al., 1988; Guterman et al., 1986; Simborg, D. W., 1981
Fetter et al., 1980; Fetter et al., 1986; Fetter et al., 1992; Coulam et al., 1991; Guterman & Dobson, 1986; Guterman et al., 1988
DRGs 1993 1 9 9 5 1996 10 1994 5.6% 44.3% 1995 ՞፣ٽॎႍ ԑ࡙ ՞ᖂҧൢາҢ)Ի* Ҭኵ)*! ҧൢາҢ)Ի*! ћ՞າҢШٽ)%* 1995 36394.99 2 2166.59 5.95 1996 75005.35 2 5022.70 6.70 1997 77944.21 15 6773.80 8.69 1998 85614.42 33 10260.53 11.98 1999 93498.82 46 12915.85 13.81 2000 98155.63 46 15684.67 15.98 2001 104629.36 46 15895.29 15.19 2002 115362.85 46 16177.39 14.02 http://www.nhi.gov.tw/02hospital/hospital_5.htm DRG 2005.01.18
1998 33 1999 2002 46 14-16% 1998 DRGs 1999 11 26 DRGs 1998 2002 1 4 1 4 DRGs 499 DRGs 2003 10 2 DRGs 12,737,642 DRGs 373,915 348,931 895,360 DRGs 169,571 380,413 673 452 52 91 12,017 12,552 5,455 DRGs 5% 525,720 10,012,440 2,929 30 183 11 2,735 case-mix index, CMI 14 DRGs i= i 1998 2002 5 7 8 564 565 522 506 j=1~5 1998 2002 k=1~nij k= k nij = 1. 1 4 1-5
2. case-mix index, CMI relative weight, RW DRGs DRG DRG RW D R G s RW RW 3. 4. 14 14 2002 2002 11 1. dummy variable 1998 1999 2002 2. ѳ֡ጓዸኧ ࢌᙴଣࢌԃࡋՐଣੰ = ԛ ࢌᙴଣࢌԃࡋᕴՐଣΓ ጓዸኧᕴک ၀ᙴଣ၀ԃࡋՐଣੰ ( 1 ij n ij n k ijk X ij X = ¦ = ) (Xijk ࢌᙴଣࢌԃಃkঁՐଣੰϐጓዸኧ jk = ࢌᙴଣࢌԃࡋCMI= ԛ ࢌᙴଣࢌԃࡋᕴՐଣΓ ࣬ჹख़ᕴک ၀ᙴଣ၀ԃࡋՐଣੰ ( 1 ij n ij n k ijk RW ij CMI = = ¦ ) (RWijk ࢌᙴଣࢌԃಃkঁՐଣੰϐ࣬ჹख़ jk = Вኧ ࢌᙴଣࢌԃࡋѳ֡Րଣ = ԛ ࢌᙴଣࢌԃࡋᕴՐଣΓ ՐଣВኧᕴک ၀ᙴଣ၀ԃࡋՐଣੰ = ( 1 ij n ij n k ijk LOS ij ALOS = = ¦ ) (LOSijk ࢌᙴଣࢌԃಃkঁՐଣੰϐՐଣВኧ jk = 14ВӕࣽӆՐଣ = ࢌᙴଣࢌԃࡋѳ֡ 14 ԛ ࢌᙴଣࢌԃࡋᕴՐଣΓ ВӕࣽӆՐଣΓԛ ၀ᙴଣ၀ԃрଣੰΓ 1 ( 1 = = ¦ RA ij n ij n k ijk RA ij RA A ) 0 14 ( 14 = RA k ijk RA jk ВӕࣽӆՐଣ ঁੰΓϐ ࢌᙴଣࢌԃಃ ଣǹ 1 14 = ijk RA ǴੰрଣࡕԖ ВӕࣽӆՐଣޑǹ ) 0 = ijk RA ց߾
8 SAS 8.2 14 repeated measures unbalanced data Dobson, 2001 1 9 9 2
Generalized Estimating Equation, GEE GEE
robust
unstructured correlation matrix
1998 578 2002 506 12.5% 1998 3,081 2002 4,334 40.7% a 30 b 2002 1998 /1998 *100% ԑ࡙ 1998ԑ 1999 ԑ 2000 ԑ 2001 ԑ 2002 ԑ 1998ڷ 2002 ᡐϽ ל ᠌឴ቹտ ড়ኵ ҁ֯՞ Ρԩ ড়ኵ ҁ֯՞ Ρԩ ড়ኵ ҁ֯՞ Ρԩ ড়ኵ ҁ֯՞ Ρԩ ড়ኵ ҁ֯՞ Ρԩ ড়ኵ )%*b ҁ֯՞ Ρԩ)%*b ϴҳᚂᏰϛЖ 7 23,486 7 25,347 6 26,709 6 31,101 6 32,843 -14.3 39.8 ϴҳୢᚂ 21 6,609 20 7,797 24 8,048 26 8,964 29 9,502 38.1 43.8 ϴҳӴୢఀᏰᚂ 31 2,608 29 3,525 21 3,652 17 4,003 13 3,957 -58.1 51.7 ϴҳӴୢᚂ 25 986 27 1,178 31 1,625 32 1,545 37 1,557 48.0 57.9 ؽҳᚂᏰϛЖ 7 41,491 8 40,647 10 37,976 11 40,144 11 39,995 57.1 -3.6 ؽҳୢᚂ 27 14,832 29 16,090 38 13,935 38 14,618 40 16,030 48.1 8.1 ؽҳӴୢఀᏰᚂ 35 6,108 36 6,229 29 5,662 30 6,602 28 6,509 -20.0 6.6 ؽҳӴୢᚂ 425 1,099 408 1,168 406 1,008 362 1,033 342 1,018 -19.5 -7.4 ᖂॎҁ֯ 578 3,081 564 3,475 565 3,475 522 4,035 506 4,334 -12.5 40.7
1 9 9 8 2 . 6 1 2002 2.86 9.58% GEE 1998 1999 2002 0.095 0.142 0.172 0.239 1998 2002 0.287 0.298 0.231 0.229 CMI 1998 0.76 2002 0.86 13.98% GEE CMI 2000 2002 1 9 9 8 0.025 0.040 0.065 1998 2000 2002 0.033 0.053 0.087 10.22% 5.86% 2000 2002 GEE unstructured correlation matrix 1998 1999 0.198 2002 1998 0.025 1998 2002 0.563 0.409 0.524 0.663 14 1998 7.86% 2002 8.62% 9.67% GEE 1 9 9 8 C M I 1999 2002 0.783% 0.455% 0.868% 0.842% 1998 2002 0.857% 0.786% 1999 DRGs DRGs
Williams, Kominski, Dowd, & Soper, 1984
a 30 14 2004 11 bGEE 1998 b1 b4 1999 2002 1998 * p<0.005 c 2002 1998 /1998 *100% ឦ 1998 2002 ԃԃ CMI 14 ԃࡋਏᔈ 1999 ԃ 2000 ԃ 2001 ԃ 2002 ԃ ѳ֡ॶ ྗৡ ѳ֡ॶ ྗৡ ѳ֡ॶ ྗৡ ѳ֡ॶ ྗৡ ѳ֡ॶ ྗৡ b1 b2 b3 b4 ѳ ֡ ጓ ዸ ኧ (ঁ ) a 2.61 0.84 2.71 0.84 2.75 0. 86 2.77 0.88 2.86 0.89 0.095 * 0.142 * 0.172 * 0.239 * 9.58 ϦҥᙴᏢύЈ 2.31 0.20 2.38 0.19 2.45 0.23 2.41 0.24 2.49 0.15 0.078 * 0 .126 * 0 .111 0.164 * 7.79 Ϧҥୱᙴଣ 2.52 0.44 2.62 0.39 2.69 0.39 2.64 0.39 2.76 0.47 0.119 * 0 .139 * 0 .069 0.144 * 9.52 ϦҥӦ௲Ꮲ 2.63 0.72 2.78 0.66 2.86 0.66 2.86 0.58 2.78 0.43 0.150 * 0 .245 * 0 .260 * 0 .005 5.70 ϦҥӦᙴଣ 2.62 0.66 3.02 0.59 2.93 0.69 2.79 0.72 2.95 0.82 0.353 * 0 .376 * 0 .220 * 0 .287 * 12.60 دҥᙴᏢύЈ 2.43 0.25 2.41 0.38 2.47 0.34 2.53 0. 31 2.59 0.21 0.067 0.100 0.166 * 0 .231 * 6.58 دҥୱᙴଣ 2.61 0.33 2.66 0.25 2.76 0.35 2.84 0.32 2.90 0.35 0.073 * 0 .137 * 0 .215 * 0 .298 * 11.11 دҥӦ௲Ꮲ 2.68 0.40 2.76 0.37 2.79 0.42 2.82 0. 40 2.90 0.39 0.041 0.055 0.137 * 0 .229 * 8.21 دҥӦᙴଣ 2.61 0.93 2.69 0.94 2.74 0.96 2.78 1.01 2.86 1.02 0.070 * 0 .124 * 0 .174 * 0 .187 * 9.58 CMI ѳ ֡ ॶ a 0.76 0.26 0.77 0.28 0.80 0.31 0.82 0.33 0.86 0.40 0.007 0.025 * 0.040 * 0.065 * 13.16 ϦҥᙴᏢύЈ 1.37 0.18 1.38 0.21 1.44 0.14 1.44 0.18 1.40 0.16 0.006 0.085 * 0.027 0.006 2.19 Ϧҥୱᙴଣ 0.94 0.16 0.94 0.15 0.92 0.13 0.89 0.13 0.89 0.13 0.020 -0.010 -0.036 -0.022 -5.32 ϦҥӦ௲Ꮲ 0.75 0.12 0.78 0.12 0.80 0.13 0.82 0.12 0.80 0.13 0.013 0.032 * 0 .053 * 0 .051 6.67 ϦҥӦᙴଣ 0.74 0.15 0.77 0.18 0.77 0.20 0.72 0. 17 0.82 0.39 0.044 * 0 .033 0.013 0.059 10.81 دҥᙴᏢύЈ 1.24 0.11 1.23 0.12 1.21 0.13 1.22 0.12 1.22 0.12 0.004 -0.014 -0.019 -0.022 -1.61 دҥୱᙴଣ 1.05 0.21 1.03 0.22 0.96 0.18 0.95 0.18 0.97 0.18 -0.014 -0.011 -0.026 -0.012 -7.62 دҥӦ௲Ꮲ 0.79 0.08 0.80 0.10 0.80 0. 11 0.82 0.13 0.82 0.13 0.006 0.006 0.022 0.023 3.80 دҥӦᙴଣ 0.71 0.26 0.72 0.28 0.76 0.33 0.78 0.36 0.83 0.45 0.006 0.033 * 0 .053 * 0 .087 * 16.90 ѳ ֡ Ր ଣ В ኧ (В ) a 6.49 2.80 6.35 2.99 6.56 4.12 6.42 3.72 6.87 4.49 -0.198 * -0.052 -0.252 -0.025 5.86 ϦҥᙴᏢύЈ 8.02 0.25 7.81 0.21 7.75 0.18 7.60 0.15 7.56 0.20 -0.247 * -0.270 * -0.436 * -0.563 * -5.74 Ϧҥୱᙴଣ 8.09 1.09 7.90 0.97 7.71 0.88 7.65 1.04 7.57 1.14 -0.105 -0.363 * -0.477 * -0.524 * -6.43 ϦҥӦ௲Ꮲ 8.95 5.75 8.86 5.48 9.75 7.31 8.80 4.42 7.97 3.17 0.057 0.410 -0.108 1.427 -10.95 ϦҥӦᙴଣ 9.37 4.58 10.71 7.31 10.11 6.66 9.29 5.45 9.30 5.65 1.102 0.729 -0.085 -0.697 -0.75 دҥᙴᏢύЈ 7.74 0.69 7.62 0.66 7.51 0.59 7.27 0.55 7. 27 0.53 -0.156 * -0.245 * -0.407 * -0.409 * -6.07 دҥୱᙴଣ 7.29 0.84 6.93 0.74 6.82 1.41 6.56 0.76 6. 63 0.81 -0.533 * -0.225 -0.751 * -0.663 * -9.05 دҥӦ௲Ꮲ 6.35 0.95 6.25 0.93 5.94 0.64 5.88 0.71 5.89 0.69 -0.134 -0.366 -0.339 -0.400 -7.24 دҥӦᙴଣ 5.97 2.36 5.72 2.09 6.04 3.94 5.95 3. 87 6.58 5.00 -0.244 0.148 -0.021 0.356 10.22 14 В ӕ ࣽ ӆ Ր ଣ (%) a 7.86 4.69 8.48 5.02 8.31 5. 44 8.59 5.36 8.62 6.35 0.783 * 0.455 * 0.868 * 0.842 * 9.67 ϦҥᙴᏢύЈ 5.32 0.88 5.64 0.99 5.30 1.08 5.50 1. 31 5.32 0.94 0.304 * 0 .056 0.193 0.054 0.00 Ϧҥୱᙴଣ 6.60 1.81 6.89 2.08 7.05 1.76 7.52 1.73 7.34 2.05 0.519 * 0 .517 * 0 .819 * 0 .857 * 11.21 ϦҥӦ௲Ꮲ 8.64 3.60 10.20 5.17 10.66 7.28 9.36 2.04 8.36 1.74 0.536 0.791 -0.725 -4.008 * -3.24 ϦҥӦᙴଣ 9.85 3.10 11.50 3.50 11.71 3.72 11.65 3.94 12.17 7.58 1.628 * 1 .992 * 2 .234 * 2 .282 23.55 دҥᙴᏢύЈ 4.99 0.74 5.53 1.00 5.33 1.06 5.42 1. 05 5.11 1.22 0.345 * 0 .045 0.255 * -0.050 2.40 دҥୱᙴଣ 6.70 1.50 6.77 1.47 6.99 1. 73 7.60 1.84 7.07 2.07 0.391 0.219 0.686 * 0.212 5.52 دҥӦ௲Ꮲ 7.53 1.60 8.28 2.05 7.83 1.89 8.30 2. 06 7.49 1.75 0.543 * -0.098 0.471 * -0.098 -0.53 دҥӦᙴଣ 7.94 5.22 8.48 5.47 8.29 5.92 8.63 6.12 8.80 7.07 0.768 * 0 .341 0.804 * 0 .786 * 10.83 :a 30 14 2004 11 1998 Կ 2002 ԃѤ ԃԋߏԭϩК c ԃࡋ 2001 ԃ 2002 ԃ ឦቫભձ 1998 ԃ 1999 ԃ 2000 ԃ
DRGs
1998 2002
9.58% 2.40%
Serden, Lindqvist, &
Rosen, 2003 1992 DRGs 0.45 0.75 16.7% DRGs 40% DRGs 1984 1987 1.9 2.7 42% 10.5%
Steinwald, B. & Dummit, L. A., 1989 DRGs CMI DRGs CMI CMI 1 CMI 1 Prospective Pay-ment AssessPay-ment Commission, ProPAC
Steinwald & Dummit, 1989
CMI DRGs 1981 1984 7.73% 2.58% 1998 2002 13.16% 3 . 2 9 % ProPAC DRGs 1984 1987 CMI 10% 3.33% DRGs DRGs DRGs CMI DRGs DRG DRG Creep Simborg, 1981;
Sorian, 1984; Glynn, 1996; Guterman et al., 1988; Johnson & Appel, 1984; Williams et
al., 1984 DRGs
2005
CMI
Iezzon 1992
DRGs
DRGs DRGs Guterman et al., 1986 DRGs 1981 1983 0.9% 1.9% 2.9% 1984 1985 DRGs 9.0% 7.7% DRGs Chulis, 1991 DRGs 1999 1998 0.198 1996 5.6% 44.3% 1998
Cody, M., Friss, L., & Hawkinson, Z. C.,
1995 Sorrentino 1989 14 DRGs Guterman et al., 1986; Feinglass et al., 1991 Fetter, 1992 DRGs DRGs Guterman et al., 1988 Feldstein 1988
Peer Review Orgranization; PRO
CMS DRGs
1984 Medicare
195
Profes-sional Standard Review Organization;
PSRO 54 PRO DRGs PRO Bhatia, Black-stock, & Ng, 2000 DRGs
CMS DRGs DRGs 2002 5 DRGs DRGs DRGs 1. 1996 2. 1 9 9 2 p p . 3 6 7 -403 3. 2005 DRGs 24 4 306-14
4. Bhatia, A. B., Blackstock, S. R., & Ng, T. S. (2000). Evolution of quality review programs for Medicare: Quality assur-ance to quality improvement. Health Care Financing Review, 22(15):69-74. 5. Chulis, G. S. (1991). Assessing Medicare s
prospective payment system for hospi-tals. Medical Care Review, 48, 167-206. 6. Cody, M., Friss, L., & Hawkinson, Z. C.
(1995). Predicting hospital profitability in short-term general community hospi-tals. Health Care Management Review., 20,77-87.
7. Coulam, R. F. & Gaumer, G. L. (1991). Medicare s prospective payment system: a critical appraisal. Health Care Financ-ing Review. Annual Supplement, 45-77. 8. Feinglass, J. & Holloway, J. J. (1991).
The initial impact of the Medicare prospective payment system on U.S. health care: a review of the literature. Medical Care Review, 48,91-115. 9. Feldstein, P. J., Wickizer, T. M., &
Wheeler, J. R. (1988). Private cost con-tainment. The effects of utilization review programs on health care use and expenditures. New England Journal of Medicine, 318(20):1310-4.
10. Fetter, R. B. (1992). Hospital payment based on diagnosis-related groups. Jour-nal of the Society for Health Systems, 3,4-15.
11. Fetter, R. B. (1984). Diagnosis related groups: the product of the hospital. Clin-ical Research, 32,336-40.
12. Fetter, R. B. & Freeman, J. L. (1986). Diagnosis related groups: product line management within hospitals. Academy of Management Review, 11,41-54. 13. Fetter, R. B., Shin, Y., Freeman, J. L.,
Averill, R. F., & Thompson, J. D. (1980). Case mix definition by diagno-sis-related groups. Medical Care,18, iii-53.
14. Glynn, K. P. (1996). Diagnosis-related group system. Can we still earn a living caring for sick people? Physician Exec-utive, 22,16-8.
15. Guterman, S. & Dobson, A. (1986). Impact of the Medicare prospective pay-ment system for hospitals. Health Care Financing Review, 7,97-114.
16. Guterman, S., Eggers, P. W., Riley, G., Greene, T. F., & Terrell, S. A. (1988). The first 3 years of Medicare prospec-tive payment: an overview. Health Care Financing Review,9,67-77.
17. Iezzoni, L. I., Restuccia, J. D., Shwartz, M., Schaumburg, D., Coffman, G. A., Kreger, B. E. et al. (1992). The utility of severity of illness information in assess-ing the quality of hospital care. The role of the clinical trajectory. Medical Care,30,428-44.
18. Johnson, A. N. & Appel, G. L. (1984). DRGs and hospital case records: impli-cations for Medicare case mix accuracy. Inquiry,21,128-34.
19. Serden, L., Lindqvist, R., & Rosen, M. (2003). Have DRG-based prospective payment systems influenced the number of secondary diagnoses in health care administrative data? Health Policy, 65, 101-7.
20. Simborg, D. W. (1981). DRG creep: a new hospital-acquired disease. New England Journal of Medicine,304,1602-4.
21. Sorrentino, E. A. (1989). Hospitals vary by LOS, charges, reimbursements and death rates. Nursing Management, 20, 54-6.
22. Steinwald, B. & Dummit, L. A. (1989). Hospital case-mix change: sicker pa-tients or DRG creep? Health Affairs, 8, 35-47.
23. Williams, S. V., Kominski, G. F., Dowd, B. E., & Soper, K. A. (1984). Method-ological limitations in case mix hospital reimbursement, with a proposal for change. Inquiry,21, 17-31.
24. Dobson, A. J. (2001). Clustered and Longitudinal Data. An Introduction to Generalized Linear Models(2nd Ed.) (pp.191-211) New York, Chapman & Hall/ CRC.
Wan-Ming Chen, Hui-Fan Chu*, Ching-Wen Chien**, Syi Su***, Shiao-Chi Wu****
To investigate the reaction of hospitals to the announcement of the coming diagnosis related groups (DRGs) payment system in 1999.
The claimed data of 12,737,642 NHI inpatients from 1998 to 2002 was used for the longitudinal analyses. The DRG code was created by BNHI DRGs soft-ware. The annual average numbers of coded diagnoses, case-mix index (CMI), av-erage length of stay (ALOS) and readmission rate (14-day) of each hospital were compared with the baseline data of 1998. The year effect was analyzed by the gen-eralized estimating equation model.
Comparing to the data in 1998, the annual average numbers of coded diag-noses, CMI, and readmission rate (14-day) was increased, but annual ALOS was decreased since 1999. The annual average numbers of coded diagnoses was in-creased since 1999. The annual average numbers of coded diagnoses of public dis-trict and private hospitals was increased more obvious than other type of hospitals. The annual CMI was increased since 2000 esp. in private district teaching hospi-tals. The ALOS of medical centers and regional hospitals was progressive de-creased since 1999. The 14-day readmission rate was also inde-creased since 1999.
It is concluded that the coming DRGs payment system has changed hospital behavior. It also was found that different property of hospitals, during the study period, have different degree of impact on hospital reaction. This change of hospi-tal behavior may influence the quality of health care.
Center for Medicare and Medicaid Services,
CMS Health Care Financing Administration, HCFA 499 DRGs
D R G 3 5 1
DRG362 / DRG437
100% DRGs DRGs 18
DRG3 comorbidity & complication, CC DRG3
CC DRG512
18 DRG57 CC DRG57 CC DRG513
