Impact of precoding on reimbursement in diagnosis-related group systems: Randomized controlled trial

Abstract

Background: Complete and correct documentation of diagnosis and procedures is essential for adequate health provider reimbursement in diagnosis-related group (DRG) systems. The objective of this study was to investigate whether daily monitoring and semiautomated proposal optimization of DRG coding (precoding) is associated with higher reimbursement per hospitalization day.

Materials and methods: This parallel-group, unblinded, randomized clinical trial randomized patients 1:1 into intervention (precoding) and control groups. Between June 12 and December 6, 2019 all hospitalized patients (1566 cases) undergoing elective or emergency surgery at the department of surgery in a Swiss hospital were eligible for this study. By random sample selection, cases were assigned to the intervention (precoding) and control groups. The primary outcome was the total reimbursement, divided by the length of stay.

Results: Of the 1205 randomized cases, 1200 (precoding group: 602) remained for intention-to-treat, and 1131 (precoding group: 564) for per-protocol analysis. Precoding increased reimbursement per hospitalization day by 6.5% (160 US dollars; 95% confidence interval 31 to 289; P = 0.015). In a regression analysis patients hospitalized 7 days or longer, precoding increased reimbursement per day by 10.0% (246 US dollars; 95% confidence interval -12 to 504; P = 0.021). More secondary diagnoses (mean [SD]: 5.16 [5.60] vs 4.39 [5.34]; 0.77; 95% confidence interval 0.15 to 1.39; P = 0.015) and nonsurgical postoperative complications (mean [SD]: 0.68 [1.45] vs 0.45 [1.12]; 0.23; 95% confidence interval 0.08 to 0.38; P = 0.002) were documented by precoding. No associated was observed regarding the length of stay, total reimbursement, or case mix index. The mean (SD) precoding time effort was 37 (27) minutes per case.

Conclusion: Physician-led precoding increases DRG-based reimbursement. Precoding is time consuming and should be focused on cases with a longer hospital stay to increase efficiency.

Keywords: Coding; Diagnosis-related group; Precoding; Surgery.