Table 2 Measurements and interpretations of outcome variables

Proportion of discharges

\(\frac{\sum\;The\;number\;of\;discharges\;from\;sample\;secondary\;or\;tertiary\;hospital}{\sum\;The\;number\;of\;discharges\;from\;each\;hospital}\)

It reflects the distribution of inpatient services. The wider the disparity in the proportion of secondary and tertiary hospitals, the poorer the implementation effectiveness of HMS is

Proportion of total medical revenue

\(\frac{\sum\;The\;total\;medical\;revenue\;of\;sample\;secondary\;or\;tertiary\;hospital}{\sum\;The\;total\;medical\;revenue\;of\;each\;hospital}\)

It reflects the distribution of service revenue. The larger the gap between the proportion of secondary and tertiary hospitals, the more uneven the revenue distribution is

Proportion of hospitalization revenue

\(\frac{\sum The\;hospitalization\;revenue\;of\;secondary\;or\;tertiary\;hospital}{\sum The\;hospitalization\;revenue\;of\;each\;hospital}\)

It reflects the distribution of inpatient service revenue. The larger the gap between the proportion of secondary and tertiary hospitals, the more uneven the hospitalization revenue distribution is

HHI

\({\sum }_{i=2}^{2}{\left(\frac{{X}_{i}}{X}\right)}^{2}={\sum }_{i=2}^{2}{S}_{i}^{2}\)(Where \({X}_{i}\) represents the number of discharges from secondary or tertiary hospitals; \(X\) denotes the total number of discharges in the entire inpatient services market; \({S}_{i}\) indicates the share of discharges from secondary or tertiary hospitals within the overall inpatient services market.)

It reflects the degree of competition in the inpatient services market. A higher HHI indicates a greater degree of market concentration and monopoly, and indirectly reflects the uneven distribution of inpatient service between secondary and tertiary hospitals