Background: This study investigates association modified category medical specialization (CMS) and hospital charge, length of stay
(LOS), and mortality among lumbar spine disease inpatients.
Methods: This study used National Health Insurance Service–cohort sample database from 2002 to 2013, using stratified representative
sampling released by the National Health Insurance Service. A total of 56,622 samples were analyzed. The primary analysis
was based on generalized estimating equation model accounting for correlation among individuals within each hospital.
Results: Inpatients admitted with lumbar spine disease at hospitals with higher modified CMS had a shorter LOS (estimate, -1.700;
95% confidence interval [CI], -1.886 to -1.514; p<0.0001). Inpatients admitted with lumbar spine disease at hospitals with higher
modified CMS had a lower mortality rate (odds ratio, 0.635; 95% CI, 0.521 to 0.775; p<0.0001). Inpatients admitted with lumbar
spine disease at hospitals with higher modified CMS had higher hospital cost per case (estimate, 192,658 Korean won; 95% CI,
125,701 to 259,614; p<0.0001). However, inpatients admitted with lumbar spine surgery patients at hospitals with higher modified
CMS had lower hospital cost per case (estimate, -152,060 Korean won; 95% CI, -287,236 to -16,884; p=0.028). Inpatients admitted
with lumbar spine disease at hospitals with higher modified CMS had higher hospital cost per diem (estimate, 55,694 Korean won;
95% CI, 46,205 to 65,183; p<0.0001).
Conclusion: Our results showed that increase in hospital specialization had a substantial effect on decrease in hospital cost per case,
LOS, and mortality, and on increase in hospital cost per diem among lumbar spine disease surgery patients.