Association between Health Information Technology and Case Mix Index

Objectives Health information technology (IT) can assist healthcare providers in ordering medication and adhering to guidelines while improving communication among providers and the quality of care. However, the relationship between health IT and Case Mix Index (CMI) has not been thoroughly investigated; therefore, this study aimed to clarify this relationship. Methods To examine the effect of health IT on CMI, a generalized estimation equation (GEE) was applied to two years of California hospital data. Results We found that IT was positively associated with CMI, indicating that increased IT adoption could lead to a higher CMI or billing though DRG up-coding. This implies that hospitals' revenue could increase around $40,000 by increasing IT investment by 10%. Conclusions The positive association between IT and CMI implies that IT adoption itself could lead to higher patient billings. Generally, a higher CMI in a hospital indicates that the hospital provides expensive services with higher coding and therefore receives more money from patients. Therefore, measures to prevent upcoding through IT systems should be implemented.