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Infor-Med Medical Information Systems Inc. (“Infor-Med”) used gmStudio to develop an advanced Custom Upgrade Solution for their Praxis EMR Product.  Praxis® EMR is more than an electronic records (EMR/EHR) system. Praxis is a template-free medical tool. Unlike rigid and cumbersome templates, Praxis uses artificial intelligence called Concept Processing that learns from you. No other EHR allows smarter and higher quality medicine than Praxis EMR.   

Baseline Metrics




1,484K LOC Logic and 95K LOC GUI in 6,794 Files
472 Forms, 2 MDIForm, 5,094 Classes, 667 UserControls, and 528 Modules organized into 130 VBPs.


4 EXEs, 59 DLLs, 50 Controls, 11 OLE EXEs, 


85,019 unique subprograms
18,688 subroutines, 21,885 functions, 27,695 properties, 1,629 externs, 13,539 handlers, and 1,583 events. 


1,274 unique UI containers containing 9,362 instances of 737 different kinds of controls.


128,010 calls to external COM components.
The diversity of COM members is 11,542 unique members from 2,186 classes in 172 COM components.


2,572 calls to 355 unique entry-point APIs from 22 libraries.
Win32 API Calls are made from 970 different user procedures.

Project Phases

GM assisted with the following three phases of the project:

  • An Assessment, Definition, and Planning engagement
  • A Standard Upgrade Phase resulting in Standard Upgrade Solution and build-complete code for the entire Praxis system. This solution produced a direct C# translation generated from the VB6 code and a C# stub framework generated for the external COM platform dependencies.
  • A Two-week intensive knowledge transfer workshop where GM and Praxis developers reviewed and experimented with the Standard upgrade solution and learned how to reproduce and improve the results using gmStudio in the Praxis environment
  • A Custom Upgrade Phase implementing numerous custom upgrade features and providing a runnable .NET system. During this phase, GM provided only Q&A technical support and the Praxis team completed the custom upgrade in house

GM and Praxis followed the Tool Assisted Rewrite Methodology.  All three phases were completed in nine months with a staffing level of one part-time GM resource and four full-time client developers. 

The Custom Upgrade Phase was conducted over a six months period and produced a Custom Upgrade Solution that could be used to automatically rewrite the Praxis EMR codebase to C# with all of the custom upgrade features listed below.  On a fast Windows 10 development machine, the custom upgrade process runs, from start to finish, in about 10 minutes generating the 156 application projects and integrating them in a VS2019 solution.

Custom Upgrade Features

The collection of features integrated and delivered in the Custom Upgrade Solution are summarized below:

COM API/Control Upgrades

  • WebBrowser upgraded using mscomct2.Winforms.Refactor rules
  • MSXML2 upgraded using GM.msxml6.dll
  • ADODB upgrade to MigrationSupport SqlClient using msado15.dll.Refactor rules
  • MSComDlg: upgrade to WinForms CommonDialog classes using comdlg32.ocx.Refactor rules
  • MSComCtl upgraded using Refactor.mscomctl.ocx
    • ImageList/ListImage
    • ListView/ColumnHeader
    • ProgressBar
    • StatusBar/Panel
    • TabStrip/Tab
    • Toolbar/Button
    • TreeView
  • MSCOMCT2 upgraded using mscomct2.Winforms.Refactor rules
    • DTPicker
    • FlatScrollBar
    • UpDown
  • Scripting upgraded to System.IO using using Scrrun.dll.Refactor rules
    • Dictionary
    • Drive
    • Encoder
    • File
    • FileSystemObject
    • Files
    • Folder
    • TextStream
  • References to In-house C++/COM dll upgraded to COM Interop (more than 1300 referenced Coclasses)
  • References to In-house C++/ActiveX Controls upgraded to COM Interop.

 Language Upgrades

  • Coding Style: used optional parameters and named arguments
  • Line: upgrade emulated with WinForms Label.
  • Error handling: upgrade to Try/Catch; simplify On Error GoTo; Selectively removed error handlers used for stack tracing
  • ByRef/ByVal: optimize parameter marshaling
  • Variant/Object Type Inference: optimize

Structural Matters

  • Shared Files Consolidation: consolidate 22 unique shared files into assemblies referenced from the generated application projects
  • Integrate hand-coded content: 371 Replacements Rules, 15 Function Reauthor and 3 file replacement.
  • VS2019 Solution: generate a solution file integrating the full application stack: 130 translated projects, 26 stub implementations and 201 hand-coded .NET projects


  • Replaced Win32 wrapper functions with functionally-equivalent hand-coded functions or intrinsic framework APIs

Value Added Features

  • Integrate with hand-coded .NET function library
  • 4 updates of the VB6 codebase during the update process
  • 3 gmStudio Updates during the migration process implementing improvements to support some requested features

Excerpt Include
Infor-Med Medical Information Systems Testimonial (CEO)
Infor-Med Medical Information Systems Testimonial (CEO)

Excerpt Include
Infor-Med Medical Information Systems Testimonial (Development Manager)
Infor-Med Medical Information Systems Testimonial (Development Manager)