Patent Publication Number: US-7711503-B2

Title: System and method for integrating the internal and external quality control programs of a laboratory

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation of U.S. patent application Ser. No. 10/428,584, filed on May 2, 2003, which is hereby incorporated herein by reference. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     FIELD OF THE INVENTION 
     The present invention relates generally to laboratory testing services and, more particularly, to a system and method that enables a laboratory to integrate its internal and external quality control programs to thereby control the quality of its laboratory testing services. 
     BACKGROUND OF THE INVENTION 
     There are many techniques used to test the functionality of laboratory instruments for the purpose of controlling the quality of laboratory testing services. One common practice is to test a stable specimen having predetermined characteristics (also known as a quality control specimen) and verify that the test result falls within a predicted range of acceptable values (also known as a control range) for a specified laboratory test. Typically, the control range is either derived from the manufacturer of the quality control material, arrived at by internal laboratory testing (i.e., by applying internal laboratory statistical data to a control rule), or a combination of the two. If the test result falls within the control range, the laboratory instrument is deemed to be functioning properly and is thus suitable for testing actual patient specimens. On the other hand, the laboratory instrument is deemed to be malfunctioning if the test result does not fall within the control range. This practice is referred to as the internal quality control program of the laboratory. 
     In addition to implementing an internal quality control program, many laboratories participate in external quality control programs (also known as peer-group quality control programs). A typical peer-group quality control program consists of a collection of participating laboratories that test quality control specimens from the same source and submit the test results to a central agency. The central agency then computes group statistical summaries of the submitted test results and sends reports back to the participating laboratories. In this manner, each participating laboratory is able to review reports that quantify the variation in test results experienced among participating laboratories. 
     In the past, the participating laboratories would record a month&#39;s worth of test results and mail the results to the central agency at the end of the month. This step would take approximately 35 days. The central agency would then compile the test results received from the participating laboratories, compute group statistical summaries of the test results, and mail reports back to the participating laboratories. This step would take approximately 15-25 days. The disadvantage to this practice was that the inherent time delay (approximately 50-60 total days) limited the usage of the reports to a retrospective look at the quality of the testing services provided by the participating laboratories. As a result, even if the reports indicated a malfunction of a particular laboratory instrument, hundreds or thousands of actual patient specimens may have already been tested by the instrument. 
     With the advent of the Internet and other communication networks, many peer-group quality control programs are now able to process test results dynamically on a real-time basis. In practice, a participating laboratory transmits test results to the central agency over the Internet on a regular basis. The central agency then receives the test results, updates the group statistical summaries to include the newly transmitted test results, and immediately transmits reports back to the participating laboratory over the Internet. The advantage to this practice is that the participating laboratory receives the reports in a much timelier fashion than the previous mail-in approach. 
     Traditionally, the internal quality control program of a laboratory has functioned independently of the external quality control program. The reports received from the central agency (whether in hard-copy form via mail or in electronic form via the Internet) are typically reviewed by someone in a managerial role within the laboratory for the purpose of identifying extreme variations between the data in the group statistical summaries and the internal laboratory statistical data used for internal laboratory testing. If only small variations are detected, nothing is done to the laboratory test system and the internal quality control program remains unchanged. However, if extreme variations are detected, it may provoke an inquiry as to the origin of the variations to thereby trigger a re-calibration of one or more laboratory instruments. Thus, the external quality control program is only utilized to correct large errors in the laboratory test system, while ignoring smaller and more tolerable errors. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is directed to a system and method that enables a laboratory to integrate its internal and external quality control programs to thereby control the quality of its laboratory testing services. 
     The system of the invention comprises a storage device and a processor operable to maintain in the storage device a database identifying various sets of relational data. One set of relational data comprises a plurality of laboratory tests and the internal laboratory statistical data corresponding to each of the laboratory tests. Another set of relational data comprises the plurality of laboratory tests and the group statistical summary data corresponding to each of the laboratory tests. Yet another set of relational data comprises the plurality of laboratory tests and the control rules corresponding to each of the laboratory tests. The processor is also operable to calculate a control range for a specified laboratory test by applying the group statistical summary data (and, in some cases, the internal laboratory statistical data) to the control rule corresponding to the specified laboratory test. Preferably, the processor is also operable to receive a test result from a laboratory instrument, and determine whether the test result falls within the calculated control range for the specified laboratory test. 
     Similarly, the computerized method of the invention comprises maintaining a database identifying a plurality of laboratory tests and the corresponding internal laboratory statistical data, group statistical summary data and control rules. The method also comprises calculating a control range for a specified laboratory test by applying the group statistical summary data (and, in some cases, the internal laboratory statistical data) to the control rule corresponding to the specified laboratory test. Preferably, the method also comprises receiving a test result from a laboratory instrument, and determining whether the test result falls within the calculated control range for the specified laboratory test. 
     The present invention will be better understood from the following detailed description of the invention, read in connection with the drawings as hereinafter described. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of a system for integrating the internal and external quality control programs of a laboratory, in accordance with the present invention. 
         FIG. 2  is a block diagram of a first exemplary embodiment of one of the laboratories of  FIG. 1 . 
         FIG. 3  is a block diagram of a second exemplary embodiment of one of the laboratories of  FIG. 1 . 
         FIG. 4  is a block diagram of a third exemplary embodiment of one of the laboratories of  FIG. 1 . 
         FIG. 5  is a block diagram of an exemplary embodiment of the central agency of  FIG. 1 . 
         FIGS. 6A and 6B  are flow charts of a method for integrating the internal and external quality control programs of a laboratory, in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
     The present invention is directed to a system and method that enables a laboratory to integrate its internal and external quality control programs to thereby control the quality of its laboratory testing services. The invention will be described hereinbelow with reference to various technical terms, including “processor,” “storage device” and “database.” It should be understood that as used herein (including in the claims), the term “processor” means either a single processor that performs the described processes or a plurality of processors that collectively perform the described processes; the term “storage device” means either a single storage device that stores the described database(s) or a plurality of storage devices that collectively store the described database(s); and the term “database” means either a single database that identifies the described sets of data or a plurality of databases that collectively identify the described sets of data. Thus, the system and method may be implemented with any number of processor(s), storage device(s) and database(s) without departing from the scope of the invention. 
     Referring to  FIG. 1 , a system in accordance with the present invention is designated generally as reference numeral  10 . System  10  includes a plurality of participating laboratories  12   a - 12   h  in communication with a central agency  14  over a plurality of communication links  16   a - 16   h . Although eight laboratories have been shown in  FIG. 1  (as would be customary for applications involving hospital and reference laboratories), it should be understood that system  10  may include hundreds or even thousands of laboratories. As will be described in greater detail hereinbelow, each of laboratories  12   a - 12   h  is able to integrate its internal and external quality control programs by utilizing the group statistical summary data generated by central agency  14  in connection with the computation of control ranges for its internal laboratory testing. 
     Communication links  16   a - 16   h  may comprise any type of communication network that is capable of transporting data between laboratories  12   a - 12   h  and central agency  14 , such as the Internet. Of course, other types of communication networks could also be used, such as any type and/or combination of local area networks, wide area networks, X.25, and ATM. Alternatively, communication links  16   a - 16   h  may comprise any type of dedicated line between laboratories  12   a - 12   h  and central agency  14 . 
     As will now be described with reference to  FIGS. 2 ,  3  and  4 , participating laboratories  12   a - 12   h  may have the same system configuration, different system configurations, or a combination of the two (i.e., some laboratories may have the same system configuration and others may have different system configurations). To show the various ways in which laboratories  12   a - 12   h  could be implemented, three exemplary embodiments of system configurations for laboratories  12   a - 12   h  will be described hereinbelow with reference to laboratories  12   a ,  12   b  and  12   c . One skilled in the art will understand, however, that other system configurations could also be implemented in accordance with the present invention. 
     Referring now to  FIG. 2 , a first exemplary embodiment of a system configuration for participating laboratories  12   a - 12   h  is shown with reference to laboratory  12   a . Laboratory  12   a  includes one or more laboratory instruments  20  connected to a laboratory information system (LIS)  22 , which is in turn connected to one or more workstations  24  used by laboratory workers. While laboratory instruments  20 , LIS  22  and workstations  24  are shown as being co-located together within the same laboratory, it should be understood that one or more of these system elements could be located at a remote location (with suitable connections to the other system elements). 
     As is known in the art, laboratory instruments  20  may be utilized to perform a variety of different laboratory tests on quality control specimens prior to testing actual patient specimens. Laboratory instruments  20  may include identical instruments from the same manufacturer, different instruments from the same manufacturer, or different instruments from a variety of manufacturers. Examples of such laboratory instruments include the Olympus AU2700, the Abbott CELL-DYN 1700, the Vitros 950, the DPC Immulite 2000, the Bayer Rapidpoint 400, and the Dade Behring PFA 100. Of course, other types of laboratory instruments could also be used. Although three laboratory instruments  20  have been shown in  FIG. 2  for ease of illustration, it should be understood that laboratory  12   a  may include any number of laboratory instruments that are required for the provision of laboratory testing services. Typically, each of laboratory instruments  20  is connected to LIS  22  via an RS-232 serial connection, although other types of connections could also be used. 
     LIS  22  comprises a computing system that includes a processor  26  and a storage device  28 . Examples of well-known computing systems that are suitable for use with the present invention include server computers, multiprocessor computers and mainframe computers, although other computing systems could also be used. Processor  26  is operable to execute computer-readable instructions stored on a computer-readable medium to thereby perform the various processes of the present invention, as will be described in greater detail hereinbelow. The computer-readable instructions may be coded using the Delphi programming language, although other programming languages could also be used, such as C, C++, Visual Basic, Java, Smalltalk, Eiffle, PERL and FORTRAN. The computer-readable medium may include any type of computer memory, such as floppy disks, conventional hard disks, CD-ROMS, Flash ROMS, nonvolatile ROM and RAM. 
     Workstations  24  each comprise a computing system, such as a personal computer or a character terminal, which may be used by a laboratory worker to initiate certain processes of the invention (e.g., the performance of laboratory tests on laboratory instruments  20  and/or the synchronization of data between laboratory  12   a  and central agency  14 ). Although two workstations  24  have been shown in  FIG. 2  for ease of illustration, it should be understood that laboratory  12   a  may include any number of workstations that are required for the provision of laboratory testing services. 
     Workstations  24  and LIS  22  preferably operate in a client-server environment, wherein each of workstations  24  operates as the “client” and LIS  22  operates as the “server.” Workstations  24  communicate with LIS  22  via a communication network  30 , such as an Ethernet network, a token ring network, or any other type of local area network or wide area network. Of course, other types of communication networks could also be used. 
     Referring still to  FIG. 2 , processor  26  of LIS  22  is operable to maintain in storage device  28  a database  32  that identifies various sets of relational data, including laboratory tests/test results, laboratory tests/internal laboratory statistical data, laboratory tests/group statistical summary data, and laboratory tests/control rules. Each set of relational data is preferably maintained in a separate table within database  32 , although other database configurations could also be used. Of course, it should be understood that LIS  22  may include any relational database software that is suitable for maintaining the various sets of relational data in storage device  28 . 
     A first set of relational data  34  maintained within database  32  comprises a plurality of laboratory tests  34   a  and the test results  34   b  corresponding to each of the laboratory tests  34   a . The test results  34   b  for each of the laboratory tests  34   a  consist of a collection of test results that have been obtained from laboratory instruments  20  during the internal testing of quality control specimens within laboratory  12   a . The first set of relational data will hereinafter be referred to as the “test results table  34 .” 
     A second set of relational data  36  maintained within database  32  comprises the plurality of laboratory tests  36   a  and the internal laboratory statistical data  36   b  corresponding to each of the laboratory tests  36   a . The internal laboratory statistical data  36   b  consists of the statistical data (e.g., mean, median, standard deviation, coefficient of variation, standard deviation index, coefficient of variation index) derived from the test results  34   b  stored within test results table  34 . As such, the internal laboratory statistical data  36   a  is based solely on the test results originating from laboratory  12   a . The second set of relational data will hereinafter referred to as the “internal statistics table  36 .” 
     A third set of relational data  38  maintained within database  32  comprises the plurality of laboratory tests  38   a  and the group statistical summary data  38   b  corresponding to each of the laboratory tests  38   a . As will be described in greater detail hereinbelow, the group statistical summary data  38   b  consists of the statistical data (e.g., mean, median, standard deviation, coefficient of variation, standard deviation index, coefficient of variation index) generated by central agency  14  for each of the laboratory tests. As such, the group statistical summary data  38   b  is based on the test results collected from all of the participating laboratories of system  10 . The third set of relational data will hereinafter be referred to as the “group statistics table  38 .” 
     A fourth set of relational data  40  maintained within database  32  comprises the plurality of laboratory tests  40   a  and the control rules  40   b  corresponding to each of the laboratory tests  40   a . Each of the control rules  40   b  consists of a formula that yields a lower limit value and an upper limit value, which together define a range of acceptable values (also known as a control range) for each of the laboratory tests. When performing a specified test on a quality control specimen, the test system is deemed to be in control when the test result falls within the control range and out of control when the control range is exceeded. The fourth set of relational data will hereinafter be referred to as the “control rules table  40 .” 
     In accordance with the present invention, the control rules  40   b  stored within control rules table  40  may be expressed in a variety of different ways. Some of the control rules may be expressed solely as a function of the group statistical summary data (e.g., group mean, group median, group standard deviation, group coefficient of variation, group standard deviation index, group coefficient of variation index) generated by central agency  14 . For example, for some laboratory tests, the control rule may be expressed as a target plus or minus an absolute concentration (e.g., group mean±1 mg/dL). For other laboratory tests, the control rule may be expressed as a target plus or minus a percentage (e.g., group median±10%). For yet other laboratory tests, the control rule may be expressed as a target plus or minus the distribution of a survey group (e.g., group mean±3 group standard deviations). Thus, it can be seen that regardless of the type of control rule, the calculated control range is based solely on the group statistical summary data. 
     Other control rules may be expressed as a function of both the group statistical summary data (e.g., group mean, group median, group standard deviation, group coefficient of variation, group standard deviation index, group coefficient of variation index) generated by central agency  14  and the internal laboratory statistical data (e.g., internal mean, internal median, internal standard deviation, internal coefficient of variation, internal standard deviation index, internal coefficient of variation index) for laboratory  12   a . For example, for some laboratory tests, the control rule may be expressed as a target plus or minus the distribution of a survey group (e.g., group mean±2 internal standard deviations). For other laboratory tests, the control rule may be expressed as a combination of two different control rules that must both be met for the test system to be deemed in control (e.g., internal mean±3 internal standard deviations, and, group mean±1.5 group standard deviations). For yet other laboratory tests, the control rule may be expressed relative to the standard deviation index (e.g., ((internal mean−group mean)/group standard deviation)&gt;2) or the coefficient of variation index (e.g., (internal coefficient of variation/group coefficient of variation)&gt;1.5). Thus, it can be seen that in either case, the calculated control range is based in part on the group statistical summary data and in part on the internal laboratory statistical data. 
     While various types of control rules have been described hereinabove, it should be understood to one skilled in the art that other types of control rules that may be expressed as a function of the group statistical summary data generated by central agency  14  and/or the internal laboratory statistical data for laboratory  12   a  could also be used. 
     Referring still to  FIG. 2 , processor  26  of LIS  22  is also operable to initiate the performance of various laboratory tests on laboratory instruments  20 , preferably in response to commands entered by laboratory workers via workstations  24 . Prior to performing a specified laboratory test on actual patient specimens, it is common practice to test at least one quality control specimen to verify that the test result falls within the control range for the specified laboratory test. To do so, the quality control specimen is tested on one of laboratory instruments  20  (i.e., the laboratory instrument to be used for testing the actual patient specimens), and the test result generated for that quality control specimen is transmitted from the laboratory instrument to processor  26 . It should be understood that this process is repeated for each of the various quality control specimens that are tested on laboratory instruments  20 . 
     Upon receipt of the new test results from laboratory instruments  20 , processor  26  is operable to transfer the new test results to test results table  34  for storage in relation to the appropriate laboratory tests. Processor  26  is also operable to re-compute the internal laboratory statistical data for the laboratory tests from the collection of test results stored within test results table  34  (which now includes the new test results). Processor  26  is then operable to transfer the updated internal laboratory statistical data to internal statistics table  36  for storage in relation to the appropriate laboratory tests. 
     Processor  26  is further operable to evaluate the new test results received from laboratory instruments  20  to determine whether laboratory instruments  20  are “in control” or “out of control.” To do so, processor  26  is operable to calculate the control ranges for the laboratory tests run on laboratory instruments  20 . For example, for those laboratory tests having a control rule that is expressed solely as a function of the group statistical summary data, processor  26  is operable to calculate the control range by applying the group statistical summary data stored within group statistics table  38  to the control rule stored within control rules table  40 . Alternatively, for those laboratory tests having a control rule that is expressed as a function of both the group statistical summary data and the internal laboratory statistical data, processor  26  is operable to calculate the control range by applying the group statistical summary data stored within group statistics table  38  and the internal laboratory statistical data stored within internal statistics table  36  to the control rule stored within control rules table  40 . Processor  26  is then operable to compare the new test results to the calculated control ranges to determine whether the new test results fall within the calculated control ranges (whereby laboratory instruments  20  are deemed to be “in control”) or whether one or more of the new test results exceed the control ranges (whereby one or more laboratory instruments  20  are deemed to be “out of control”). Preferably, processor  26  is operable to display the new test results, calculated control ranges and control status on workstations  24  so that a laboratory worker may manually review the data to determine whether a re-calibration of one or more laboratory instruments  20  is required. 
     Referring still to  FIG. 2 , processor  26  of LIS  22  is also operable to transmit the new test results received from laboratory instruments  20  over communication link  16   a  to central agency  14 . Preferably, the new test results are transmitted to central agency  14  in response to a synchronization command entered by a laboratory worker via one of workstations  24 . Alternatively, the new test results may be transmitted to central agency  14  at a specified date and time (e.g., every 8 hours of operation), or, the new test results may be transmitted to central agency  14  automatically as they become available. As will be described in greater detail with reference to  FIG. 5 , central agency  14  then updates the group statistical summary data with the new test results received from laboratory  12   a , and automatically transmits the updated group statistical summary data back over communication link  16   a  to processor  26 . 
     Upon receipt of the updated statistical summary data from central agency  14 , processor  26  is operable to evaluate the updated group statistical summary data for correspondence with the current group statistical summary data stored in group statistics table  38 . Preferably, the values of the updated group statistical summary data are compared with the values of the current group statistical summary data to determine whether there is a variance of more than a specified percentage (e.g. 10%). If there is such a variance, processor  26  is operable to flag the updated group statistical summary data for display on workstations  24  so that a laboratory worker may manually review the data for possible adjustment. If there is not such a variance, processor  26  is then operable to transfer the updated group statistical data to group statistics table  38  for storage in relation to the appropriate laboratory tests. 
     Referring now to  FIG. 3 , a second exemplary embodiment of a system configuration for participating laboratories  12   a - 12   h  is shown with reference to laboratory  12   b . Laboratory  12   h  includes one or more laboratory instruments  42  connected to a first laboratory information system (first LIS)  44 , which is in turn connected to a second laboratory information system (second LIS)  46 . Preferably, first LIS  44  and second LIS  46  are both connected to one or more workstations  48  via a communication network  49  for operation in a client-server environment. While laboratory instruments  42 , first LIS  44 , second LIS  46  and workstations  48  are shown as being co-located together within the same laboratory, it should be understood that one or more of these system elements could be located at a remote location (with suitable connections to the other system elements). 
     It can be seen that most of the system elements of laboratory  12   b  are the same as those of laboratory  12   a . For example, laboratory instruments  42  are the same as laboratory instruments  20 , and workstations  48  are the same as workstations  24 . However, as will now be described, first LIS  44  and second LIS  46  are utilized in place of LIS  22  (which, as described hereinabove, is specifically configured to perform all of the various processes of the present invention). 
     First LIS  44  comprises a conventional computing system that is used to initiate the performance of various laboratory tests on laboratory instruments  42  and receive the test results therefrom. It should be understood that because first LIS  44  is a conventional system, it is not capable of utilizing the group statistical summary data generated by central agency  14  in connection with the internal testing of quality control specimens. 
     Second LIS  46  comprises a computing system that includes a processor  50  and a storage device  52 . Examples of well-known computing systems that may be used for second LIS  46  include server computers, multiprocessor computers and mainframe computers, although other computing systems could also be used. Processor  50  is operable to execute computer-readable instructions stored on a computer-readable medium to thereby perform the additional processes of the present invention that are not performed by first LIS  44 . The computer-readable instructions may be coded using the Delphi programming language, although other programming languages could also be used, such as C, C++, Visual Basic, Java, Smalltalk, Eiffle, PERL and FORTRAN. The computer-readable medium may include any type of computer memory, such as floppy disks, conventional hard disks, CD-ROMS, Flash ROMS, nonvolatile ROM and RAM. 
     In accordance with the present invention, processor  50  of second LIS  46  is operable to maintain in storage device  52  a database  54  that includes a test results table  56 , an internal statistics table  58 , a group statistics table  60  and a control rules table  62  (which are the same as the tables described hereinabove with reference to laboratory  12   a ). Processor  50  is also operable to import test results from first LIS  44  into second LIS  46  and transfer the imported test results to test results table  56  for storage in relation to the appropriate laboratory tests. Alternatively, the test results may be imported directly from laboratory instruments  42  into second LIS  46 , or, manually entered into second LIS  46 . 
     Processor  50  is also operable to re-compute the internal laboratory statistical data for the laboratory tests from the collection of test results stored within test results table  56 , which now includes the imported test results. Processor  50  is then operable to transfer the updated internal laboratory statistical data to internal statistics table  58  for storage in relation to the appropriate laboratory tests. 
     Processor  50  is further operable to evaluate the imported test results to determine whether laboratory instruments  42  are “in control” or “out of control.” To do so, processor  50  is operable to calculate the control ranges for the laboratory tests corresponding to the imported test results. Processor  26  is then operable to compare the imported test results to the calculated control ranges to determine whether the imported test results fall within the calculated control ranges (whereby laboratory instruments  42  are deemed to be “in control”) or whether one or more of the imported test results exceed the control ranges (whereby one or more of laboratory instruments  42  are deemed to be “out of control”). Preferably, processor  50  is operable to display the imported test results, calculated control ranges and control status on workstations  48  so that a laboratory worker may manually review the data to determine whether a re-calibration of one or more laboratory instruments  42  is required. 
     Referring still to  FIG. 3 , processor  50  of second LIS  46  is also operable to transmit the imported test results over communication link  16   b  to central agency  14 . Preferably, the imported test results are transmitted to central agency  14  in response to a synchronization command entered by a laboratory worker via one of workstations  48 . Alternatively, the imported test results may be transmitted to central agency  14  at a specified date and time, or, the imported test results may be transmitted to central agency  14  automatically as they become available. As will be described in greater detail with reference to  FIG. 5 , central agency  14  then updates the group statistical summary data with the imported test results received from laboratory  12   b , and automatically transmits the updated group statistical summary data back over communication link  16   b  to processor  50 . 
     Upon receipt of the updated statistical summary data from central agency  14 , processor  50  is operable to evaluate the updated group statistical summary data for correspondence with the current group statistical summary data stored in group statistics table  60 . Preferably, the values of the updated group statistical summary data are compared with the values of the current group statistical summary data to determine whether there is a variance of more than a specified percentage. If there is such a variance, processor  50  is operable to flag the updated group statistical summary data for display on workstations  48  so that a laboratory worker may manually review the data for possible adjustment. If there is not such a variance, processor  50  is then operable to transfer the updated group statistical data to group statistics table  60  for storage in relation to the appropriate laboratory tests. 
     Referring now to  FIG. 4 , a third exemplary embodiment of a system configuration for participating laboratories  12   a - 12   h  is shown with reference to laboratory  12   c . Laboratory  12   c  includes one or more laboratory instruments  64  connected to a laboratory information system (LIS)  66 , which is in turn connected to one or more workstations  68  via a communication network  67  for operation in a client-server environment. While laboratory instruments  64 , LIS  66  and workstations  68  are shown as being co-located together within the same laboratory, it should be understood that one or more of these system elements could be located at a remote location (with suitable connections to the other system elements). 
     It can be seen that many of the system elements of laboratory  12   c  are the same as those of laboratory  12   b . For example, laboratory instruments  64  are the same as laboratory instruments  42 , workstations  68  are the same as workstations  48 , and LIS  66  is the same as first LIS  44  (i.e., a conventional computing system that is used to initiate the performance of various laboratory tests on laboratory instruments  64  and receive the test results therefrom). However, laboratory  12   c  does not include a system element that corresponds to second LIS  46 . Rather, the processes performed by second LIS  46  are performed by central agency  14  (which will be described in greater detail hereinbelow with reference to  FIG. 5 ). 
     In order for central agency  14  to perform such processes, it must receive the test results from laboratory  12   c . Accordingly, in one embodiment, a Web server  69  is provided that allows a laboratory worker to transfer the test results via e-mail over communication link  16   c  to central agency  14 . Of course, other file exchange protocols could also be used, such as HTTP or FTP. Alternatively, in another embodiment, Web server  69  is provided to allow a laboratory worker to manually enter the test results via a manual input screen provided on an Internet web site of central agency  14 . However, this alternative is not practical for laboratories that process large amounts of test results. 
     Finally, it should be understood that laboratories  12   a ,  12   b  and  12   c  have been described and illustrated hereinabove to show the variety of system configurations that are possible for laboratories  12   a - 12   h . One skilled in the art will understand that other system configurations for laboratories  12   a - 12   h  could also be implemented in accordance with the present invention. 
     As will now be described with reference to  FIG. 5 , an exemplary embodiment of a system configuration for central agency  14  is shown. Central agency  14  comprises a central computing system  70  that includes a central processor  72  and a central storage device  74 . Examples of well-known computing systems that are suitable for use with the present invention include server computers, multiprocessor computers and mainframe computers, although other computing systems could also be used. 
     Central processor  72  is operable to execute computer-readable instructions stored on a computer-readable medium to thereby perform the various processes of the present invention, as will be described in greater detail hereinbelow. The computer-readable instructions may be coded using the Delphi programming language, although other programming languages could also be used, such as C, C++, Visual Basic, Java, Smalltalk, Eiffle, PERL and FORTRAN. The computer-readable medium may include any type of computer memory, such as floppy disks, conventional hard disks, CD-ROMS, Flash ROMS, nonvolatile ROM and RAM. 
     Referring still to  FIG. 5 , central processor  72  is operable to maintain in central storage device  74  a central database  76  that identifies various groups and sets of relational data, as described hereinbelow. Each set of relational data is preferably maintained in a separate table within central database  76 , although other database configurations could also be used. Of course, it should be understood that central computing system  70  may include any relational database software that is suitable for maintaining the various sets of relational data in central storage device  74 . 
     A first group of relational data  78  maintained within central database  76  comprises a plurality of individual sets of relational data (one for each of the participating laboratories of system  10 ). Each set of relational data comprises a plurality of laboratory tests and the collection of test results corresponding to each of the laboratory tests for that particular laboratory. This group of relational data will hereinafter be referred to as the “group of test results tables  78 .” 
     Another set of relational data  80  maintained within central database  76  comprises the plurality of laboratory tests and the group statistical summary data corresponding to each of the laboratory tests (which is derived from testing carried out by specified groups of laboratory instruments within the participating laboratories of system  10 ). This set of relational data will hereinafter be referred to as the “group statistics table  80 .” 
     Another group of relational data  82  maintained within central database  76  comprises a plurality of individual sets of relational data (one for each of the participating laboratories of system  10  that have the system configuration of laboratory  12   c ). Each set of relational data comprises the plurality of laboratory tests and the internal laboratory statistical data corresponding to each of the laboratory tests for that particular laboratory. This group of relational data will hereinafter referred to as the “group of internal statistics tables  82 .” 
     Yet another group of relational data  84  maintained within central database  76  comprises a plurality of individual sets of relational data (one for each of the participating laboratories of system  10  that have the system configuration of laboratory  12   c ). Each set of relational data comprises the plurality of laboratory tests and the control rules corresponding to each of the laboratory tests for that particular laboratory. This group of relational data will hereinafter be referred to as the “group of control rules tables  84 .” 
     Referring still to  FIG. 5 , central processor  72  is also operable to periodically receive tests results from the various participating laboratories of system  10 . For a participating laboratory that has the system configuration of laboratory  12   a  (see  FIG. 2 ) or laboratory  12   b  (see  FIG. 3 ), the test results are transmitted from the participating laboratory over a communication link for receipt by central processor  72 . Upon receipt of the test results, central processor  72  is operable to transfer the test results to the appropriate table within the group of test results tables  78  (i.e., the table assigned to that particular laboratory) for storage in relation to the appropriate laboratory tests. Central processor  26  is also operable to re-compute the group statistical summary data for the laboratory tests from the collection of test results stored within the group of test results tables  78 , which now includes the new test results. Central processor  72  is then operable to transfer the updated group statistical summary data to group statistics table  80  for storage in relation to the appropriate laboratory tests. In addition, central processor  72  is operable to transmit the updated group statistical summary data back over the communication link to the participating laboratory. 
     For a participating laboratory that has the system configuration of laboratory  12   c  (see  FIG. 4 ), the test results are either sent via e-mail over a communication link for receipt by central processor  72  or are manually entered via a manual input screen provided on the Internet web site of central agency  14  for receipt by central processor  72 . Regardless of the manner in which the test results are received, central processor  72  is operable to transfer the test results to the appropriate table within the group of test results tables  78  (i.e., the table assigned to that particular laboratory) for storage in relation to the appropriate laboratory tests. 
     Central processor  72  is also operable to re-compute the internal laboratory statistical data for the laboratory tests from the collection of test results stored within the appropriate table of the group of test results tables  78  (i.e., the table assigned to that particular laboratory), which now includes the new test results. Central processor  72  is then operable to transfer the updated internal laboratory statistical data to the appropriate table of the group of internal statistics tables  82  (i.e., the table assigned to that particular laboratory) for storage in relation to the appropriate laboratory tests. 
     In addition, central processor  72  is operable to re-compute the group statistical summary data for the laboratory tests from the collection of test results stored within the group of test results tables  78 , which now includes the new test results. Central processor  72  is then operable to transfer the updated group statistical summary data to group statistics table  80  for storage in relation to the appropriate laboratory tests. 
     Central processor  72  is further operable to evaluate the new test results to determine whether the laboratory instruments of the participating laboratory are “in control” or “out of control.” To do so, central processor  72  is operable to calculate the control ranges for the laboratory tests corresponding to the new test results. Central processor  72  is then operable to compare the new test results with the calculated control ranges to determine whether the new test results fall within the calculated control ranges (whereby the laboratory instruments are deemed to be “in control”) or whether one or more of the new test results exceed the control ranges (whereby one or more of the laboratory instruments are deemed to be “out of control”). 
     Finally, for a participating laboratory that sends its test results to central agency  14  via e-mail, central processor  72  is preferably operable to send an e-mail back to the laboratory summarizing the new test results, calculated control ranges and control status so that a laboratory worker may review the data to determine whether a re-calibration of one or more of the laboratory instruments is required. Alternatively, for a participating laboratory that manually enters its test results on the Internet web site of central agency  14 , central processor  72  is preferably operable to post the new test results, calculated control ranges and control status to the Internet web site so that a laboratory worker may access the Internet web site (preferably via appropriate authentication procedures, such as a user ID and password) and review the data to determine whether a re-calibration of one or more of the laboratory instruments is required. 
     Turning now to  FIGS. 6A and 6B , a flow diagram of a computerized method in accordance with the present invention is provided with reference to blocks  100 - 124 . At block  100 , a database is maintained that identifies various sets of relational data, including laboratory tests/test results, laboratory tests/internal laboratory statistical data, laboratory tests/group statistical summary data, and laboratory tests/control rules. Then, at block  102 , the set of relational data containing the laboratory tests/group statistical summary data is initialized to contain the updated group statistical data received from a central agency. 
     At block  104 , various laboratory tests are performed on various quality control specimens using one or more laboratory instruments. Then, at block  106 , the new test results generated by the laboratory instruments are transferred to the set of relational data containing the laboratory tests/test results for storage in relation to the appropriate laboratory tests. 
     Next, at block  108 , the internal laboratory statistical data is re-computed for each of the laboratory tests using the test results stored within the set of relational data containing the laboratory tests/test results (which now includes the new test results). Then, at block  110 , the updated internal laboratory statistical data is transferred to the set of relational data containing the laboratory tests/internal laboratory statistical data for storage in relation to the appropriate laboratory tests. 
     At block  112 , the new test results are evaluated to determine whether the laboratory instruments are “in control” or “out of control.” To do so, the control ranges for the laboratory tests are calculated and compared with the new test results. If the new test results fall within the calculated control ranges, then the laboratory instruments are deemed to be “in control” and the method proceeds directly to block  114 . However, if one or more of the new test results exceeds the calculated control ranges, then one or more of the laboratory instruments are deemed to be “out of control.” In such a case, the new test results, calculated control ranges and control status are flagged for manual review by a laboratory worker to determine whether re-calibration of one or more of the laboratory instruments is required. 
     At block  114 , the new test results are transmitted to the central agency. The new test results may be transmitted to the central agency in response to a synchronization command entered by a laboratory worker, at a specified date and time, automatically as new test results become available, via e-mail, or by manual entry. The central agency  14  then updates the group statistical summary data with the new test results. Then, at block  116 , the updated group statistical summary data is received from the central agency. 
     At block  118 , the updated group statistical summary data is evaluated for correspondence with the current group statistical summary data stored in the set of relational data containing the laboratory tests/group statistical summary data. Specifically, the values of the updated group statistical summary data are compared with the values of the current group statistical summary data to determine the variance therebetween. At block  120 , it is determined whether the variance is acceptable. If the variance is not acceptable, at block  122  the updated group statistical summary data is flagged for manual review by a laboratory worker for possible adjustment. On the other hand, if the variance is acceptable, at block  124  the updated group statistical summary data is transferred to the set of relational data containing the laboratory tests/group statistical summary data for storage in relation to the appropriate laboratory tests. Finally, the method returns to step  104  to repeat the processes of blocks  106 - 124  for another group of various laboratory tests performed on various quality control specimens using one or more laboratory instruments. 
     It should be apparent to one skilled in the art that the system and method of the present invention described and illustrated hereinabove provide several advantages over traditional practices that do not integrate the internal and external quality control programs of a laboratory. For example, over time, the “tweaking” of small adjustments into the group statistical summary data generated by a central agency will reduce the variation in test results experienced among participating laboratories of an external quality control program. 
     Also, because participating laboratories are continually updating the group statistical summary data used to calculate the control ranges for internal laboratory testing, certain test results may be accepted that would otherwise be considered erroneous under a traditional analysis (which does not utilize the group statistical summary data). Conversely, certain test results may be considered erroneous that would otherwise be accepted under a traditional analysis. 
     In addition, because a majority of the federally mandated laboratory performance standards (e.g., outlined in CLIA Regulations  493  and  909 - 959 ) are specified as a function of the group statistical summary data, the use of the group statistical summary data to calculate the control ranges for internal laboratory testing allows laboratories to base their internal quality control practices on the same principles used by federal regulatory agencies to evaluate laboratory quality. 
     While the present invention has been described and illustrated hereinabove with reference to several exemplary embodiments, it should be understood that various modifications could be made to these embodiments without departing from the scope of the invention. Therefore, the invention is not to be limited to the specific systems and methods described and illustrated hereinabove, except insofar as such limitations are included in the following claims.