Abstract:
The task is to provide a system which supports smooth patient referral from a referral source medical institution to a referral destination medical institution and which particularly prevents readmission due to cases that are difficult to determine simply based on patient attributes or due to the quality of medical services. To achieve this task, a referral difficult degree calculation unit calculates a referral difficulty degree which quantifies the risk that a patient cannot be discharged because a referral destination cannot be found, in consideration of a readmission risk calculated by a readmission risk calculation unit, the geographical distance between the patient and the referral destination medical institution, the total number of patients accepted, and the number of beds available. This referral difficulty degree is outputted to an output unit of the referral source medical institution or the referral destination medical institution.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a hospital information system technique in the field of medical services and particularly a cooperation system between hospitals for regional medical services. 
       BACKGROUND ART 
       [0002]    As a result of patients&#39; preference for large hospitals and specialists, there is a tendency for patients to concentrate constantly at medical institutions in the secondary medical area and the tertiary medical area. Also, patients who need long-term medical care including home care are increasing because of changes in disease patterns such as lifestyle-related illness. Therefore, there is a need to proceed with the division of functions of medical institutions and further promote regional medical cooperation structures. To this end, it is desired that a regional network should be constructed between acute hospitals and backup hospitals so as to construct an environment where cooperation can be made smoothly for patients. 
         [0003]    PTL 1 is a system in which, with reference to a medical cooperation database, a backup hospital (referral destination medical institution) that is suitable as a referral destination for a patient of an acute hospital (referral source medical institution) is selected and referred to. Conditions of selection include patient&#39;s condition, available hospital ward, medication, institution, medical treatment fee, region of location, number of specialists, presence/absence of examination equipment and facilities, and the like. 
       CITATION LIST 
     Patent Literature 
       [0004]    PTL 1: JP-A-2005-258854 
       SUMMARY OF INVENTION 
     Technical Problem 
       [0005]    As described above, as a conventional regional medical cooperation system, there is a system in which, when a patient is referred to a referral destination medical institution from a referral source medical institution, patient information is shared and the referral destination medical institution is searched for on the basis of the location, symptoms and the like, thus realizing interactive matching (management of acceptance request and permission) between the referral source medical institution and the referral destination medical institution. However, there is a problem that, in the referral of the patient, the patient cannot be discharged from the hospital because no referral destination is found. There is referral difficulty (with a disease for which it is difficult to predict the date of discharge, an advanced bed control technique is needed and it is difficult to accept a referral destination) due to cases where it is difficult to make a decision simply based on patient attributes, for example, where the patient is readmitted as the conditions worsen even if a referral destination is found, or the like. Therefore, solving this problem is a task. 
         [0006]    In the case of the foregoing PTL 1, there is a system for searching for a hospital that matches search conditions. However, the quality of medical services such as readmission is not taken into account. 
         [0007]    Thus, to realize smooth regional medical cooperation, it is difficult to achieve sufficient effects with the disclosed conventional technique. 
       Solution to Problem 
       [0008]    To solve the above problem, a regional medical cooperation system for supporting patient referral to a referral destination medical institution from a referral source medical institution in regional medical cooperation is provided, the regional medical cooperation system including a medical information system, a regional medical cooperation server at the referral source medical institution, and a medical institution system at the referral destination medical institution, wherein the medical information system has a medical information database which stores medical information including patient information, and wherein the regional medical cooperation server has a medical information system cooperation unit which acquires the medical information stored in the medical information database, a readmission risk calculation unit which calculates a readmission risk that is a risk of being readmitted to the referral source medical institution from the referral destination medical institution on the basis of the medical information acquired from the medical information system cooperation unit, a server referred patient input unit which accepts an input of a first referred patient, and a server output unit which calculates and displays on a screen a referral destination medical institution and a first readmission risk corresponding to the first referred patient. 
       Advantageous Effect of Invention 
       [0009]    By determining the risk of the patient referral in advance, including the readmission risk, which is the risk of being readmitted to the referral source medical institution from the referral destination medical institution, it is possible to improve the patient referral including reduction in the burden on the patient, and realize promotion of a regional medical cooperation structure required by an increase in the number of referred patients. Thus, the turnover of patients rises, contributing to hospital management. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0010]      FIG. 1  is a schematic view of the configuration of a regional medical cooperation system according to the invention. 
           [0011]      FIG. 2  is a first configuration view of the regional medical cooperation system according to the invention. 
           [0012]      FIG. 3  is a view of the hardware configuration of the regional medical cooperation system according to the invention. 
           [0013]      FIG. 4  is a first flowchart showing a flow of processing in the regional medical cooperation system according to the invention. 
           [0014]      FIG. 5  is a first example showing a screen at a referral source medical institution in the regional medical cooperation system according to the invention. 
           [0015]      FIG. 6  is a first view showing a referred patient registration database in the regional medical cooperation system according to the invention. 
           [0016]      FIG. 7  is a first example showing a screen at a referral destination medical institution in the regional medical cooperation system according to the invention. 
           [0017]      FIG. 8  is a view showing an institution environment database in the regional medical cooperation system according to the invention. 
           [0018]      FIG. 9  is a first flowchart showing a flow of processing in a readmission risk calculation unit in the regional medical cooperation system according to the invention. 
           [0019]      FIG. 10  is a first view showing a medical information database in the regional medical cooperation system according to the invention. 
           [0020]      FIG. 11  is a second view showing the medical information database in the regional medical cooperation system according to the invention. 
           [0021]      FIG. 12  is a first view showing a readmission risk database in the regional medical cooperation system according to the invention. 
           [0022]      FIG. 13  is a second flowchart showing a flow of processing in the readmission risk calculation unit in the regional medical cooperation system according to the invention. 
           [0023]      FIG. 14  is a second view showing the readmission risk database in the regional medical cooperation system according to the invention. 
           [0024]      FIG. 15  is a first flowchart showing a flow of processing in a referral difficulty degree calculation unit in the regional medical cooperation system according to the invention. 
           [0025]      FIG. 16  is a second flowchart showing a flow of processing in the regional medical cooperation system according to the invention. 
           [0026]      FIG. 17  is a second view showing the referred patient registration database in the regional medical cooperation system according to the invention. 
           [0027]      FIG. 18  is a second example showing the screen at the referral destination medical institution in the regional medical cooperation system according to the invention. 
           [0028]      FIG. 19  is a second example showing the screen at the referral source medical institution in the regional medical cooperation system according to the invention. 
           [0029]      FIG. 20  is a second configuration view of the regional medical cooperation system according to the invention. 
           [0030]      FIG. 21  is a flowchart showing a flow of processing in a discharge delay risk calculation unit in the regional medical cooperation system according to the invention. 
           [0031]      FIG. 22  is a second flowchart showing a flow of processing in the referral difficulty degree calculation unit in the regional medical cooperation system according to the invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0032]    Hereinafter, the best mode for carrying out the invention will be described. 
       Example 1 
       [0033]      FIG. 1  is a schematic view of the configuration of a regional medical cooperation system according to the invention. The regional medical cooperation system shown in  FIG. 1  is made up of a medical information system  10 , a regional medical cooperation server  20 , and a medical institution system  30 . If the regional medical cooperation server  20  is installed at a referral source medical institution and the medical institution system  30  is installed at a referral destination medical institution, there is often a plurality of medical institution systems  30 . However, the regional medical cooperation server  20  may be installed at a data center, and there maybe only one medical institution system  30 . Moreover, the regional medical cooperation server  20  and the medical institution system  30  are connected with each other via a network. 
         [0034]      FIG. 2  is a view of the detailed configuration of the regional medical cooperation system according to the invention. The medical information system  10  is made up of an input/output unit  100 , a control unit  101 , and a medical information database  102 . The regional medical cooperation server  20  is made up of a medical information system cooperation unit  201 , a readmission risk calculation unit  202 , a readmission risk database  203 , an institution environment database  204 , a referral difficulty degree calculation unit  205 , a referral source screen configuration processing unit  206 , a referral source input unit  207 , a referral source output unit  208 , and a referred patient registration database  209 . The medical institution system  30  is made up of a referral destination screen configuration processing unit  301 , a referral destination input unit  302 , and a referral destination output unit  303 . Here, the readmission risk is the risk of being readmitted to the referral source medical institution from the referral destination medical institution. Also, the referral difficulty degree indicates the degree of difficulty in patient referral. 
         [0035]    The hardware configuration of this system will be described.  FIG. 3  shows a view of the hardware configuration for realizing the regional medical cooperation system according to the invention (each component shown in  FIG. 1 ). The medical information database  102 , the readmission risk database  203 , the discharge delay risk database  204  and the referred patient registration database  209  are made up of an external storage device  604  or the like, represented by an HDD (Hard Disk Drive) device. The control unit  101 , the medical information system cooperation unit  201 , the readmission risk calculation unit  202 , the referral difficulty degree calculation unit  205 , the referral source screen configuration processing unit  206  and the referral destination screen configuration processing unit  301  can realize various kinds of processing as a predetermined program is unfolded and started up in a central processing unit  603 , a memory  602  or the like. The input/output unit  100 , the referral source output unit  208  and the referral destination output unit  303  can be realized by a liquid crystal display  601  or a monitor utilizing a CRT (Cathode-Ray Tube) or the like. Also, an output is made on a medium such as paper. The input/output unit  100 , the referral source input unit  207  and the referral destination input unit  302  can be realized by a keyboard  600 , a mouse, or a pen tablet. 
         [0036]      FIG. 4  shows a flowchart showing the outline of the regional medical cooperation system. First, a referred patient group acquired via the medical information system cooperation unit  201  is displayed on the referral source input unit  207  of the regional medical cooperation server  20  (S 401 ). Next, as the user at the referral source medical institution selects a referred patient via the referral source input unit  207 , the referral source screen configuration processing unit  206  acquires a referral destination medical institution candidate, and the referral difficulty degree, the institution information and the readmission risk of the candidate, acquired from the referral difficulty degree calculation unit  205 , and displays these on the referral source output unit  208  (S 402 ). S 402 , and particularly the institution information, the readmission risk and the referral difficulty degree, will be described in detail using  FIGS. 8 to 15 . Next, as the referral source user selects a referral destination medical institution candidate via the referral source input unit  207 , the referred patient and the referral destination medical institution are registered on the referred patient registration database  209  (S 403 ). Subsequently, in the medical institution system  30  of the referral destination medical institution, the referral destination screen configuration processing unit  301  acquires the corresponding patient information from the referred patient registration database  209  and displays this patient on the referral destination output unit  303  (S 404 ). The user at the referral destination medical institution responds with a determination on the acceptance of the patient requested by the referral source, via the referral destination input unit  302  (S 405 ). 
         [0037]    Now, the flow of the operations by the user at the referral source medical institution (S 401  to S 403 ) will be described in detail. An example of display on the referral source output unit  208  is shown in  FIG. 5 . The screen shown in  FIG. 5  is made up of a patient selection section  501 , a condition setting section  502 , a referral destination medical institution candidate display section  503 , and a referral request button  504 . In the patient selection section  501 , inpatients are displayed as a referred patient group from a patient admission basic information table (described in detail with reference to  FIG. 10 ) for managing admission and discharge information of one instance, via the medical information system cooperation unit  201 . As the user selects a referred patient, a referral destination medical institution candidate that meets the setting items in the patient selection section  501  and the condition setting section  502 , and the referral difficulty degree, the institution information and the readmission risk of the candidate are displayed on the cooperating hospital display section  503 . In this example, the case where three institutions are displayed as referral destination medical institution candidates when a patient PO with ischemic heart disease is selected is illustrated. 
         [0038]    In this manner, referral destination medical institution candidates can be displayed in consideration of the readmission risk, and promotion of a regional medical cooperation structure required by increase in the number of referred patients can be realized. 
         [0039]    Subsequently, as the user selects one of the referral destination medical institution candidates and presses the referral request button  504 , the referred patient and the referral destination medical institution are registered on the referred patient registration database  209 . Also, the lineup display in the referral destination medical institution candidate display section  503  may be controlled according to an item order set by the user in the condition setting section  502 . For instance, in the example of  FIG. 5 , the case where as the user first sets the referral difficulty degree in the condition setting section  502 , the lineup display is done in the referral destination medical institution candidate display section  503  according to the value of the referral difficulty degree, is illustrated.  FIG. 6  shows an example of a referred patient registration table in the referred patient registration database  209 . In this example, the case where an A institution is requested to accept the patient PO with ischemic heart disease inputted in  FIG. 5  is illustrated. Moreover, any patient who requires urgency may be able to be registered on the referred patient registration database  209 . 
         [0040]    By thus selecting a referral destination medical institution displayed with the readmission risk, it is possible to decide a patient referral destination medical institution in consideration of the readmission risk and promote the success of patient referral. 
         [0041]    Next, the flow of the operations by the user at the referral destination medical institution (S 404  to  5405 ) will be described. An example of display on the referral destination output unit  303  is shown in  FIG. 7 . The screen shown in  FIG. 7  is made up of a condition setting button  701 , a condition display section  702 , a referred patient display section  703 , a referral approval button  704 , and a referral rejection button  705 . As the condition setting button  701  is pressed to set a display condition such as disease name, the display condition that is set is displayed in the condition display section  702 . Moreover, a patient that matches the condition is extracted from the referred patient registration database  209  and displayed in the referred patient display section  703 . As the user selects an acceptable patient from the patients displayed in the referred patient display section  703  and presses the referral approval button  704 , that the patient is acceptable is transmitted to the referral source medical institution. Meanwhile, if the referral rejection button  705  is pressed, that the acceptance is difficult is transmitted. Also, the reason for rejection may be inputted with the referral rejection button  705 . In this example, the case where P0 and P20 are selected and the referral approval button  704  is pressed, is illustrated. 
         [0042]    In this manner, understanding and communication between the referral destination medical institution selected in consideration of the readmission risk and the referral source medical institution can be carried out easily 
         [0043]    Now, the institution information, the readmission risk and the referral difficulty degree in  5402  of the flowchart of  FIG. 4  will be described in detail using  FIGS. 8 to 15 . First, the institution information will be described.  FIG. 8  shows an example of an institution information table and a disease basic information table stored in the institution environment database  204 . The institution information table has basic information about the referral destination medical institution. In this example, the institution information table has the institution name, the postcode, the number of beds, and the number of beds available. The disease basic information table has information by institution and by disease. In this example, the disease basic information table has the number of doctors and the total number of patients accepted up until now. 
         [0044]    Next, the readmission risk will be described. The readmission risk is the risk that the patient is readmitted to the referral source medical institution as the patient&#39;s condition worsens after the patient is transferred from the referral source medical institution to the referral destination medical institution.  FIG. 9  shows a flowchart relating to the calculation of the readmission risk. First, the readmission risk calculation unit  202  calculates the readmission risk based on the information acquired from the medical information database  102  in the medical information system  10  via the medical information system cooperation unit  201  (S 901 ). A specific calculation method will be described in the following paragraphs. Subsequently, the calculated readmission risk is stored in the readmission risk database  203  (S 902 ). This readmission risk calculation processing is not carried out every time a patient referral is made, but is carried out by batch processing or the like in advance, for example, once a month, or the like. 
         [0045]    Now, with respect to the method for calculating the readmission risk, a specific example of the medical information database  102  that is to be input data will be described first, and two kinds of calculation methods will be described.  FIGS. 10 and 11  show an example of a patient basic information table, a patient admission basic information table and a conducted practice information table stored in the medical information database  102 . The patient basic information table is a table for managing basic information of patients and has the patient code, gender, date of birth, and postcode. In this example, the case where a patient P0 is male, was born in 1950 and has a postcode 111-5214 is illustrated. The patient admission basic information table is a table for managing information about admission and discharge of one instance and has the patient code, date of admission, date of discharge, disease name, referral destination medical institution name, and readmission flag. The readmission flag of 1 indicates that readmission takes place, and 0 indicates that readmission does not take place. Also, for example, if one patient is admitted five times, five records are generated. In this example, it is shown that the patient P0 is admitted from January 10 to January 14 for ischemic heart disease, then transferred to the A institution without readmission. As for P1, it is shown that the patient is admitted twice, for hepatoma and for ischemic heart disease each, and readmitted for ischemic heart disease. The date of discharge, the referral destination medical institution name, and the readmission flag for P3 are shown as “-”. This means that the patient is currently in hospital. The conducted practice information table shown in  FIG. 11  is a table for managing records of medical practices conducted, and has the medical practice, date thereof, and the like. In this example, for example, the case where medical practices such as orientation and blood pressure checkup are conducted on the patient P0 is illustrated. 
         [0046]    Next, two kinds of methods for calculating the readmission risk will be described. In both methods, the patient basic information table, the patient admission basic information table and the conducted practice information table are inputted, and the strength of the correlation between the risk of readmission, and the medical practice and patient attributes, is quantified. First, a method using the type II quantification method, which is a first calculation method, will be described. In this example, calculation is carried out, using the gender, disease name, age, referral destination medical institution and practice, as explanatory variables (variable for explaining an external criterion), and using the readmission flag as the external criterion (variable to be predicted), from the patient basic information table, the patient admission basic information table and the conducted practice information table, which are to be input data. In the readmission risk database  203 , the category score (also referred to as a discriminant coefficient; a criterion for discriminating whether an element falls into one group or not) calculated as a result of the type II quantification method is stored.  FIG. 12  shows a first example of a readmission risk table stored in the readmission risk database  203 . In this example, the case where the category score of a category male is 0.01 is illustrated. Also, it can be understood that since the category score value of ischemic heart disease is high, it largely influences the readmission risk. 
         [0047]    In this way, the readmission risk can be calculated and it is possible to decide a referral destination medical institution in consideration of the readmission risk.  
         [0048]    Next, a method using association rule mining, which is a second calculation method, will be described.  FIG. 13  is a flowchart relating to the method for calculating the readmission risk, in which S 901  is detailed. First, using the data in the medical information database  102  as an input, association rules are generated by association rule mining (association analysis) (S 9011 ). Next, an association rule having a readmission flag “1” in an association rule conclusion part is extracted, and all the sets of the other attributes than the readmission flag are extracted on the basis of the extracted association rule (S 9012 ). Finally, with respect to each set of attributes extracted in S 9012 , the proportion of the readmission flag being “1” is calculated, using the total number of inpatients who match the set of attributes, as the denominator, and the result is the readmission risk (S 9013 ).  FIG. 14  shows a readmission risk table stored in the readmission risk database  203 . This table shows the readmission risk, using the gender, practice (technique), practice (other), season, age, disease name and institution name, as explanatory variables. For example, for a patient with ischemic heart disease who is 65 years old or above and is admitted to the B institution in winter, the readmission risk is 30. Also, “-” indicates that the variable has little influence on the readmission risk.  
         [0049]    In this method, compared with the first calculation method, only the categories that influence the readmission risk and the combinations thereof are extracted and therefore it is possible to store only effective combinations of categories in the readmission risk database  203 . Thus, it is possible to realize reduction in the capacity of the database, and a higher speed of readmission risk calculation (S 1504 ) at the time of extracting the referral difficulty degree, described next. 
         [0050]    Finally, the referral difficulty degree will be described. The referral difficulty degree is the degree of difficulty in patient referral between the referral destination and the referral source.  FIG. 15  is a flowchart relating to a method for calculating the referral difficulty degree. First, the data is acquired from the readmission risk database  203  ( FIGS. 12 ,  14  or the like) and the institution environment database  204  ( FIG. 8  or the like) (S 1501 ). Next, a referred patient selected at the referral source input unit  207  is acquired via the referral source screen configuration processing unit  206  (S 1502 ). Next, the patient attributes of the patient extracted in S 1502  are acquired via the medical information system cooperation unit  201  (S 1503 ). Next, the readmission risk of this patient is extracted with respect to each institution on the basis of the patient attributes extracted in S 1503  and the readmission risk table extracted in S 1501  (S 1504 ). In the case of the readmission risk table shown in  FIG. 12 , the category score is used as the value of the readmission risk. In the case of the readmission risk table shown in  FIG. 14 , if there is a corresponding record, the “risk” field is used as the value of the readmission risk. If there is none, there is no influence on the readmission risk and therefore “0” can be used as the value of the readmission risk. Finally, quantitative variables are extracted or converted from the institution information extracted in S 1501 , the patient attributes extracted in S 1503  and the readmission risk calculated in S 1504 , and the referral difficulty degree for each institution is calculated on the basis of these quantitative variables (S 1505 ). It is also possible to carry out only one of the extraction and conversion. With respect to the conversion of a quantitative variable, for example, a postcode is a qualitative variable, whereas the distance calculated from the postcode of the patient and the postcode of the institution is a quantitative variable. The extraction of a quantitative variable refers to extracting a category that can be handled without carrying out processing like conversion, such as the number of beds available, as a quantitative variable. As an example of calculation of the referral difficulty degree, the distance calculated from the postcode of the patient and the postcode of the institution, the number of beds available, the total number of patients accepted (the total number of patients accepted up until now), and the readmission risk may be normalized in such a way that the average value equals the standard deviation (distribution of different quantitative variables is handled on the basis of the same standard and thus made comparable with each other), and the sum of the normalized values maybe defined as the referral difficulty degree. This referral difficulty degree is calculated when “the referred patient is selected via the referral source input unit  207  in S 402 ”. 
         [0051]    Moreover, by taking the total number of patients accepted into account in the calculation of the referral difficulty degree, it is possible to evaluate the experience point of each institution and therefore improve the quality of medical services. 
         [0052]    With such a regional medical cooperation system, the readmission risk can be calculated on the basis of the past data and the referral destination medical institution can be thus decided. It is possible to facilitate the success of referral and realize the promotion of a regional medical cooperation structure required by increase in the number of referred patients. Moreover, by taking the total number of patients accepted into account in the calculation of the referral difficulty degree, it is possible to evaluate the experience point of each institution and therefore improve the quality of medical services. 
       Example 2 
       [0053]      FIG. 16  is a second flowchart showing the outline of the regional medical cooperation system according to the invention. First, the referral source user registers a referred patient via the referral source input unit  207  (S 1601 ). Next, with respect to a patient registered in S 1601  and having a referral difficulty degree and a readmission risk equal to or below a threshold that is set in advance by the referral source user, the referral source screen configuration processing unit  206  acquires both the referral difficulty degree acquired from the referral difficulty degree calculation unit  205  and the referral destination medical institution candidate (S 1602 ). Next, the referral source screen configuration processing unit  206  registers the acquired information of S 1602  on the referred patient registration database  209  (S 1603 ).  FIG. 17  shows a referred patient registration table stored in the referred patient registration database  209 . As the categories in this table, the institution name, patient name, disease name, readmission risk, geographical condition, referral difficulty degree, and referral destination acceptance availability are provided. The number of categories is larger than in  FIG. 6 . This is for the purpose of presenting various kinds of information to the referral destination medical institution in S 1604 . 
         [0054]    Next, the referral destination screen configuration processing unit  301  acquires patient information corresponding to the own institution from the referred patient registration database  209 , and displays this patient on the referral destination output unit  303  (S 1604 ). Next, as the referral destination user inputs, via the referral destination input unit  302 , a determination on acceptance of the patient requested by the referral source, the patient is registered on the referred patient registration database  209  via the referral destination screen configuration processing unit  301  (S 1605 ). These two kinds of processing (S 1604 , S 1605 ) will be described in detail using the specific example of  FIG. 18 .  FIG. 18  shows an example of the screen displayed on the referral destination output unit  303 . The screen shown in  FIG. 18  is made up of a condition setting button  1801 , a condition display section  1802 , a referred patient display section  1803 , an acceptance available button  1804 , and an acceptance unavailable button  1805 . As display conditions such as disease name are set via the condition setting button  1801 , the display conditions that are set are displayed in the condition display section  1802 . Moreover, patients who match the conditions are extracted from the referred patient registration database  209  and displayed in the referred patient display section  1803 . As the referral destination user selects an acceptable patient from the patients displayed in the referred patient display section  1803  and presses the acceptance available button  1804 , that the patient is acceptable is transmitted to the referral source medical institution. Meanwhile, if the acceptance unavailable button  1805  is pressed, that the acceptance is difficult is transmitted. In this example, the case where P0 and P100 are selected and where the acceptance available button  1804  is pressed is illustrated. Thus, in the referred patient registration database  209  shown in  FIG. 17 , “available” is shown in the referral destination acceptance availability category for P0. 
         [0055]    Finally, the determination on acceptance acquired from the referred patient registration database  209  is displayed on the referral source output unit  208 , and the referral source user approves the result of response from the referral destination user, via the referral source input unit  207  (S 1606 ). This processing will be described in detail using the screen example of  FIG. 19 . The screen shown in  FIG. 19  is made up of a patient selection section  1901 , a candidate list  1902 , a selected patient information display section  1903 , a selected referral destination medical institution information display section  1904 , and a referral approval button  1905 . As the user selects a patient from the patient selection section  1901 , referral destination medical institution candidates available for acceptance (that is, having “1” shown in the referral destination acceptance availability category) are displayed in the candidate list  1902 . At the same time, detailed information of the selected patient is displayed in the selected patient information display section  1903 . Subsequently, as a referral destination medical institution candidate is selected in the candidate list  1902 , detailed information of the selected referral destination medical institution is displayed in the selected referral destination medical institution information display section  1904 . As the user presses the referral approval button  1905  after browsing through these pieces of information, the referral to the selected referral destination medical institution is finalized and no referral is made to the other referral destination medical institution candidates that are not selected. 
         [0056]    Now, the difference between the flowchart shown in  FIG. 4  and the flowchart shown in  FIG. 16  will be described. In the flowchart shown in  FIG. 4 , a referral request is made by the referral source medical institution with reference to the readmission risk and the referral difficulty degree in advance, and only the requested patient is displayed at the referral destination medical institution. Meanwhile, in the flowchart shown in  FIG. 16 , of the patients registered at the referral source medical institution, a patient corresponding only to a referral destination medical institution that satisfies a readmission risk and a referral difficulty degree below a preset threshold is displayed. 
         [0057]    With such a regional medical cooperation system, simply by registering a patient at the referral source medical institution, it is possible to realize a referral request to a proper referral destination medical institution, in which the success of referral between the referral destination medical institution and the referral source medical institution is increased in consideration of the readmission risk. Also, since only a patient with a referral difficulty degree below a threshold is referred to the referral destination medical institution, it is possible to improve the motivations for the progress of medical skills at medical institutions, such as measures for reducing readmissions. 
       Example 3   
       [0058]      FIG. 20  is a second configuration view showing the outline of the regional medical cooperation system according to the invention. A discharge delay risk calculation unit  210  and a discharge delay risk database  211  are newly added to the configuration view shown in  FIG. 2 , and the calculation method in the referral difficulty degree calculation unit  205  is changed. This configuration makes it possible to consider variations in the number of days spent in hospital at the time of calculating the referral difficulty degree, since the number of days spent in hospital largely varies even with the same disease, due to the patient condition or the like, for example, and consequently readmission may take place. The discharge delay risk calculation unit  210  in this configuration can realize various kinds of processing as a predetermined program is unfolded and started up in the central processing unit  603  and the memory  602  shown in  FIG. 3 , or the like. Also, the discharge delay risk database  211  is made up of the external storage device  604  shown in  FIG. 3 , or the like. 
         [0059]    Next,  FIG. 21  shows a flowchart of the discharge delay risk calculation unit  210 . First, the data in the medical information database  102 , particularly information of the number of days spent in hospital shown in the patient admission basic information table of  FIG. 10 , is acquired via the medical information system cooperation unit  201  (S 2101 ). Next, the deviation of the number of days spent in hospital is calculated for each disease on the basis of the acquired data (S 2102 ). Finally, the deviation calculated in S 2102  is stored in the discharge delay risk database  211  as the discharge delay risk (S 2103 ). While the deviation is calculated in this example, a distribution or coefficient of variation may be defined as the discharge delay risk. 
         [0060]      FIG. 22  shows a second flowchart relating to a method for calculating the referral difficulty degree. The difference from the flowchart shown in  FIG. 15  is that the discharge delay risk is taken into account. First, the data is acquired from the readmission risk database  203 , the institution environment database  204  and the discharge delay risk database  211  (S 2201 ). Next, a referred patient selected at the referral source input unit  207  is acquired via the referral source screen configuration processing unit  206  (S 2202 ). Next, the patient attributes of the patient extracted in S 2202  are acquired via the medical information system cooperation unit  201  (S 2203 ). Next, the readmission risk of this patient is calculated for each institution on the basis of the patient attributes extracted in S 2203  and the readmission risk table extracted in S 2201  (S 2204 ). These S 2202  to S 2204  are the same processing as S 1502  to S 1504 . Next, the discharge delay risk of this patient is calculated on the basis of the patient attributes extracted in S 2203  and the discharge delay risk table extracted in S 2201  (S 2205 ). This S 2205  is the processing added to take the discharge delay risk into account. Finally, quantitative variables are extracted or converted from the institution information extracted in S 2201 , the patient attributes of the patient extracted in S 2204 , the readmission risk calculated in S 2204  and the discharge delay risk calculated in S 2205 , and the referral difficulty degree is calculated for each institution on the basis of these quantitative variables (S 2206 ). For example, the distance calculated from the postcode of the patient and the postcode of the institution, the number of beds available, the total number of patients accepted, the readmission risk and the discharge delay risk may be normalized in such a way that the average value equals the standard deviation, and the sum of the normalized values maybe defined as the referral difficulty degree. 
         [0061]    With such a regional medical cooperation system, by calculating and utilizing the discharge delay risk, it is possible to consider cases where the number of days spent in hospital largely varies even with the same disease. Thus, the referral destination medical institution can predict the scheduled date of hospital visit and the variation risk thereof, and this facilitates bed control at the referral destination medical institution. Moreover, it is possible to increase the success of patient referral between the referral source medical institution and the referral destination medical institution. 
       INDUSTRIAL APPLICABILITY 
       [0062]    The invention relates to a hospital information system technique in the field of medical services and particularly useful as a technique for supporting smooth cooperation between hospitals for regional medical services. 
       REFERENCE SIGNS LIST 
       [0000]    
       
           10  medical information system 
           100  input/output unit 
           101  control unit 
           102  medical information database 
           20  regional medical cooperation server 
           201  medical information system cooperation unit 
           202  readmission risk calculation unit 
           203  readmission risk database 
           204  institution environment database 
           205  referral difficulty degree calculation unit 
           206  referral source screen configuration processing unit 
           207  referral source input unit 
           208  referral source output unit 
           209  referred patient registration database 
           210  discharge delay risk calculation unit 
           211  discharge delay risk database 
           30  medical institution system 
           301  referral destination screen configuration processing unit 
           302  referral destination input unit 
           303  referral destination output unit 
           501  patient selection section 
           502  condition setting section 
           503  referral destination medical institution candidate display section 
           504  referral request button 
           600  keyboard 
           601  liquid crystal display 
           602  memory 
           603  central processing unit 
           604  external storage device 
           701  condition setting button 
           702  condition display section 
           703  referred patient display section 
           704  referral approval button 
           705  referral rejection button 
           1801  condition setting button 
           1802  condition display section 
           1803  referred patient display section 
           1804  acceptance available button 
           1805  acceptance unavailable button 
           1901  patient selection section 
           1902  candidate list 
           1903  selected patient information display section 
           1904  selected referral destination medical institution information display section 
           1905  referral approval button