An Analysis of Thai Diagnosis Related Group (TDRG) Reimbursement for Primary Total Knee Arthroplasty
Artit Laoruengthana MD1, Supasit Pannarunothai MD, PhD2, Supachok Rasamimongkol MD1
Affiliation : 1 Department of Orthopaedics, Faculty of Medicine, Naresuan University, Phitsanulok, Thailand 2 Centre for Health Equity Monitoring Foundation, Phitsanulok, Thailand
Background : Thai Diagnosis Related Group [TDRG] version 5 has been widely used in Thailand as a coding and information
system for managing hospital reimbursement.
Objective : The present study aimed to examine how well TDRG reflects actual inpatient costs of primary total knee
arthroplasty [TKA] at Naresuan University Hospital.
Materials and Methods : Records of patients admitted from October 2014 through September 2015 were obtained from the
hospital’s financial department. A total of 394 TKA patients were identified, including 224 patients covered under the Civil
Servant Medical Benefit Scheme [CSMBS] and 170 covered under the Universal Health Coverage Scheme [UHC].
Results : (1) The adjusted relative weights [AdjRWs] of UHC and CSMBS beneficiaries were not statistically significantly
different, although CSMBS patients had a longer average length of hospital stay [LOS]. (2) Despite the fact that bilateral
TKAs doubled the health care cost compared to unilateral TKA, the AdjRW was approximately double that for unilateral
TKA, reflecting a fair and reasonable hospital reimbursement. (3) Although the difference was not statistically significant,
we found that the variation in the cost of care for primary TKA depended on the severity of the patient’s co-morbidity, e.g.,
greater need for treatment, higher AdjRW, and longer LOS. Hospital reimbursement for patients with comorbidities was
higher than hospital care costs for patients none regardless of the severity level of the comorbidity. (4) The vendor managed
inventory [VMI] system for knee prostheses did not affect the AdjRW and did not make a statistically significant difference
in hospital profit or loss. (5) The AdjRW, LOS, and hospital net profits varied with the surgeon who performed the TKA.
Conclusion : TDRG version 5 is a reasonable system for reimbursement of patient’ cost for primary TKA, and it seems to
reimburse appropriately for comorbid TKA patients as well. Cost containment strategies that focus on shortening LOS and
cost-saving related to treatment plans managed by individual surgeons could potentially enhance the hospital’s net profit.
Keywords : Thai Diagnosis Related Group [TDRG], Reimbursement, Vendor Managed Inventory (VMI), Total knee arthroplasty
