Announcing Source Data Verification in VISION EDC

Source Data Verification 

Prelude Dynamics continues to enhance our VISION™ platform with crucial features requested by our clinical trial user community. The ability to perform Source Data Verification (SDV) in the context of EDC has become more and more important as we’re migrating away from paper. VISION’s SDV functionality operates at the field level and complements the existing form review capability. How does it work? 

Users who have permission to review forms can activate the SDV feature simply by clicking an icon on the form. When this is done, check boxes appear next to the fields on the form.


Check boxes give clinical trial monitors an easy way to see which fields still need to be verified.


Check boxes are automatically cleared if the reviewed field is later changed – letting monitors easily see which fields need to be re-reviewed, while preserving the reviewed state of other data entry elements on the formThis is a time-saver for monitors, and saving time saves money! 

These field-level SDV reviews are fully attributed and preserved in the audit trail in a 21 CFR compliant manner. 


The audit trail shows information about the user who performed the Source Data Verification.


Even though most of our clients use VISION to directly enter data as the source (eSOURCE), in some cases there might be a need for SDV. Let’s consider a few scenarios. 

Transcription of data from paper forms 

First consider the transcription of data from paper forms (or pictures of paper forms) such as subject/owner logs or paper patient reported outcome forms to EDC. In the past, Double Data Entry (DDE) was typically used for situations such as these. SDV is an improved replacement for DDE, especially when used along with a file upload that allows a copy of the original paper form to be uploaded directly to the EDC.  

Review of Adverse Events 

Monitors typically want to review Adverse Events as soon as they are entered into the EDC as part of their safety assurance responsibilitiesOccasionally, investigators haven’t completed all the information in the Adverse Event eCRF because they are still conducting analysis on the possible cause. In cases such as this, Monitors can review the data that has been already entered. When they revisit the form later, they will know which information has already been reviewed. This also works well for Concomitant Medications. 

Want to learn more? Contact us to schedule a demo and stay tuned for news of other new features such as Site Level Batch Data Entry and quick report filters! 


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Best Practices for Conducting Clinical Trial EDC User Acceptance Testing

User Acceptance Testing (UAT) is a critical component of clinical trial development using Electronic Data Capture (EDC). It’s the responsibility of the Sponsor/CRO to perform UAT prior to using the EDC to collect data in accordance with a protocol.

Early and thorough UAT can result in studies that are easy to use and monitor, and have short submission preparation timelines. We’ve found this to be especially true when our best practices for conducting UAT are followed. Our VISION EDC provides tools and features that facilitate UAT every step of the way, making it a faster and more effective process. Prelude Dynamics’ seven best practices are described in more detail below. Perhaps you have some of your own you can share with us!

  1. Thoroughly test every e-CRF
  2. Verify masking and role-dependent access
  3. Involve a site
  4. Test the electronic lab interface
  5. Consider risk factors
  6. Involve the statistician early
  7. Conduct Pre-UAT

Thoroughly test every e-CRF

This may seem obvious, but it’s surprising how often this is not done. Sometimes test personnel become complacent when most e-CRFs work as expected, and abandon test efforts early. But then during study conduct it turns out that the Investigator Signoff form – which is the typically the last subject form to be filled out – isn’t working correctly.

It’s especially important to verify that the Inclusion/Exclusion e-CRF is working correctly. Imagine the consequences to the clinical trial if subjects that should be excluded are not. Similarly, dosing calculations should be rigorously vetted.

This is a good time to check the upper and lower limits on data entry fields and to make sure all calculations are operating as intended. VISION’s embedded Field Specification displays this information for every form in the study, which facilitates this process.

Verify Masking and Role-dependent Access

There’s almost nothing worse than unmasking a study, so don’t risk it! Identify every e-CRF where the treatment group (or other masked field) is present and verify that masked roles cannot see the value in either the e-CRF or the audit trail. VISION’s Field Specification is also useful for performing this task.

Inversely, imagine that the treatment dispenser has no access to the Dosing form. Avoiding mid-study changes to permissions reduces the probability of non-contemporaneous entry of critical study data. VISION’s Study Requirements Document (SRD) Configuration can be used to verify that permissions to view, edit, review and finalize each study form have been configured correctly.

Involve a Site

Sites are ultimately one of the most critical components of any successful clinical trial. If e-CRF layouts are clumsy or non-intuitive, sites will have trouble completing them correctly. When this is the case, site enrollment may suffer due to user frustration with the EDC.

Involving one or more trusted sites early in the UAT process can provide early insight into usability issues and allow them to be corrected before the study goes live. VISION’s Feedback function can be useful in capturing site input on usability issues. Happy sites require less monitor intervention and produce cleaner data.

Test the Electronic Lab Interface

Studies that benefit from the use of electronic lab interfaces, such as those supported by IDEXX and Marshfield, enjoy more accurate and timely lab results data in their study. It’s important to coordinate with lab company personnel to assure that data required by their LIMS is included in electronic lab requests, and in the e-CRFs if necessary. It’s typical to configure study-specific parameters used for tracking and billing in the EDC, and to test the interface in a training study (or training site) prior to going live. VISION supports fully validated electronic interfaces for both IDEXX and Marshfield Labs.

Consider Risk Factors

Every study has risks, but for every risk there is a way for the EDC to assist in detecting when a risk is becoming a reality. Many EDCs support ad-hoc query functions that generate reports based on user-entered criteria.  These can be configured to generate reports pertaining to potential risks such as a high number of reactions at a drug injection site, or abnormally high blood glucose level after dosing.

Losing subjects due to lack of adequate follow up poses both a financial and a schedule risk. Tools such as the VISION Event Calendar provide ways to quickly and easily detect missed visits before a protocol deviation occurs. EDC statistics functions can also be used to view data in graphical format, which is more intuitive than rows of numbers and can be used to identify outliers.

Custom reports can be developed in the EDC that are tailored to look for specific potentially risky outcomes. These can be developed at study build time, or added later when unanticipated risks begin to arise during study conduct.

Involve the Statistician Early

Configuring the study database so that the data is organized in a way that makes it easy for the statistician to prepare the data for submission is something that is sometimes overlooked when studies are being developed. This can result in both time delays in submission and difficulty with data analysis.

We recommend entering test data into either a training study or training site, and exporting the data for analysis as part of UAT. This approach allows the statistician to take an early look at the exported data, and test it with their statistical analysis software. If changes are needed to the database to facilitate analysis, these can be made and testing prior to going live.

Conduct Pre-UAT

Pre-UAT? It’s not unusual to identify multiple study changes while testing, especially when unfamiliar with the power and flexibility of EDC. Conducting a Pre-UAT ahead of the UAT schedule can help identify and address most of these changes ahead of time. When this is done, UAT consists of verifying that all requested changes have been implemented, tested and work together in an intuitive way.

Starting study test early is generally recommended to avoid cramming test efforts into the last week prior to going live. When testing is deferred, sites have a more difficult time entering data and study conduct is more difficult and lengthy than it needs to be.


In our experience, following these best practices for performing UAT results in less risky, higher quality studies with excellent usability and data integrity. EDCs such as VISION provide many validated, integrated tools that facilitate both UAT and study conduct. Prelude Dynamics provides training in the use of these tools prior to the conduct of Pre-UAT and/or UAT. We are increasing receiving requests to deliver the data from training studies/sites as part of study closeout. This data serves to demonstrate that UAT has been conducted.

If you’d like more information about any of the tools and features discussed in this article, or would like to schedule a demo, please contact us.

VISION™ Tips & Tricks: Utilizing Summaries

Did you know that each VISION™ study comes with a set of standard Summaries?  They aggregate Subject and Site-level data, enabling faster monitoring and data validation. Standard Subject-level summaries may include Subject Status, Form Status, Query Details, and Comments (Note to Field).  Standard Site-level summaries may include Site Status, Enrollment, Form Status, Queries and Comments (Note to Field). Custom summaries are also available upon request (and include, but are not limited to Adverse Events, Deviations, Note to File, etc.).


To access a Subject or Site Summary, navigate to the Subject or Site list page and Click the “Summaries” button in the footer of the page.
Also, please note that if any Searches or Filters have been applied, the Summary data will only display the filtered data set. At the Subject level, you can view Summaries for all sites, or a specific site by specifying in the site dropdown (see Figure 1).

Figure 1. Site selection dropdown can be found in the page header.

You can then narrow the scope of the subjects you’re viewing by applying search criteria (see Figure 2).

Figure 2. Adding Search criteria can help narrow the scope.

See our Tips and Tricks on Layering Data Searches for more details on applying search criteria.

Below is a table of examples found in VISION™:

Summary cohortSummary dataDescription of Summary
SubjectSubject Visit StatusShows the most important dates per subject. (Study visit dates, study completion dates, etc.)
SubjectForm StatusShows the # of forms in-work, in-review, reviewed, finalized for each subject. Also shows the # of unresolved, resolved and reviewed queries per subject.
SubjectQuery Details Summary contains two sub-tabs, one for "Unresolved Queries" and one for "All Queries." Details include subject ID, form/field query was entered on, date, who entered the query, the query, and the time it took to resolve the query (or the time it has been open).
Subject and SiteNote to FieldShows an aggregate of the notes made to subject (or site) fields
SiteSite StatusShows aggregate enrollment by gender, screen failures, and completed study status. It can also display Form and Query status.
SiteEnrollmentShows a graph and/or table of expected versus actual enrollment per site.
SiteQuery GraphShows total versus unresolved queries. Excellent for a quick view of query status overall and for site comparison.

Please contact your Prelude Project Manager for more details or questions on this article.

A Case for HTML Archives for FDA Submission

Currently FDA official submissions must be in XML or PDF format, with the preference being the submission of at least the XML format. The rationale for these is the need to have a document that will be readable and accessible in perpetuity. This is definitely an important consideration. However, these formats contain limitations when it comes to the review, oversight and approval process as clinical reviewers are more effective “seeing” a case as a set of forms the way the Investigator filled out those forms, while analysis staff are more effective with the XML raw information. How do you handle ancillary data, such as images and graphical information that were part of the process which cannot be imbedded in XML?

Below we will present a case for allowing HTML archives to be added as a part of or one of the allowable formats for FDA submission, fundamentally to support clinical case review. The raw XML would continue to be favored format for data analysis.

HTML, Hyper Text Markup Language, is the foundation of all computer languages used to create web-based interfaces. HTML is a specialized form of XML that when combined with images and style sheets (CSS) make a web page appear as it does. The Internet has been growing exponentially since its inception transforming business and everyday life; the Internet is here to stay and so is HTML. “Billions and billions” of HTML web pages exist in the world today. HTML can be compared to the alphabet. Like the alphabet, it provides us with basic element in which we can combine in order to communicate via web pages. HTML does for computer language what the alphabet does for our language. It is safe to say HTML will stand the test of time.

One might assume that HTML requires a web server to operate, but in fact, an HTML page is just a document that resides on a computer hard drive on a server, and can also be saved locally. All browsers support “Save As” and can save a web page for later viewing when the computer is disconnected from the Internet. All that’s needed is any brand of web-browser. As such, these HTML/XML pages are safe, secure, and as perpetual as any computer file on the hard drive.

Now that we have established that HTML is a viable solution in perpetuity, let’s examine the differences between XML, PDF and HTML archives. The main differences are listed in the table below.

 XML ArchivePDF ArchiveHTML Archive
Accessing softwareXML can be imported into many database software programs as well as some spreadsheet programs. It is truly non-proprietary, and readable by humans with just a text viewer.PDFs can be read using a number of portable file document readers. The PDF format has been made public, but is proprietary and licensed by Adobe.HTML is truly non-proprietary, and can be read like XML, but looks best when combined with CSS in any browser.
Security and Virus vulnerabilityNo vulnerability.No current vulnerability but PDF enhancements may someday add scripting.HTML can have embedded JavaScript that a scanner would need to remove. These same malware detection components are included in all modern browsers.
Availability of software to access archive typeMost of these have to be purchased.Some of the readers are available free, but the population in general does not all have them.All computer users have access to free browsers.
NavigationXML is typically hierarchical which reduces duplication compared to repeating table rows. Navigation is by drilling into the hierarchy much like opening folders with subfolders.Data is presented in lengthy documents that are difficult to navigate, but that display the forms upon which data was entered. Limited capabilities to search and find information.Displays the data in the forms that they were entered in providing the viewer an experience similar to what was used when the data was input. The viewer is able to navigate through pages using the same process the data collector did.
Handling of uploaded documentsNot contained within the XML file.Usually available as separate PDFs in a separate folder with no link back to the patient or form.Documents are accessible through clicking the embedded hyperlink. Documents are in their original format or PDF.
Visibility of queries, field notations, and changes to data Prelude’s XML has queries, comments, and changes co-located with the field variable to which they apply. No separate files. However, XML while a simple structure and open format, is verbose and reviewers are challenged to view a “case” as an entity.The PDF as a screen image will show what was on the screen, but may also be a separate page or even a separate document. This can make searching and finding difficult.HTML Archives are saved web pages, and when done properly, allow users to click the hyperlinks to view and navigate the specific query, field notation or change to data related to a given field at the point of viewing the field.
Overall functionality for analysis (e.g. SAS)XML provides data that can be freely processed by many non-proprietary systems to support a data analysis.Does not allow data processing.Does not allow data processing.
Overall functionality for case reviewMost FDA personnel who review and provide study oversight are not data managers or statisticians; they are monitoring personnel who are more familiar with a paper-based analog (CRFs) process where they can look at the forms and see the data being collected in context as the Investigator staff viewed the case. XML does not provide a format that is easy for them to use.It is difficult to navigate through long PDFs of patient case report forms and to navigate between patients is nearly impossible or requires opening multiple individual patient PDFs.Provides excellent functionality allowing navigation from patient to patient and form to form in the same fashion that a person entering data would have done so. It makes the process of reviewing and providing oversight much faster because they do not have to organize the data and can focus on reviewing the data to ensure the safety and efficacy of drugs.

In conclusion, while the XML archive is a natural non-proprietary requirement for data submission because it does allow quick processing of the data in order to analyze the safety and efficacy of a drug, providing HTML data in addition is superior to PDF files in that it facilitates the case review within the same context in which the data was originally collected by Investigators. HTML will increase FDA reviewer’s confidence in the quality of the data and its outcomes.

Prelude Dynamics has initiated conversations with FDA CVM to discuss allowing HTML archives to be submitted. Among the discussion is also the possibility that Sponsors could chose to allow CVM to have access to the server in read-only mode where they could interact with the study data and even run reports, statistics and graphs within the system before final submission occurs in order to guide sponsors on any additional requirements or concerns they might have in order to help expedite the final review process, reduce the need for clarifications, and be quicker to market.


Jim Pedzinski – VP of Business Development
jpedzinski[at] – 512-476-5100 ext. 210

Inventory Management & Automatic Reordering




It is challenging for working clinics to ensure sufficient inventory of treatment and control medications or supplies are available throughout a clinical study. Prelude Dynamics was challenged to identify an inventory management system that was smart enough to know when medications and supplies were used at the patient level, keep track of current inventory, and reorder supplies as they became low. One challenge to accomplish this is the varied sizes of clinics and expected enrollment for each site, which required something more sophisticated than a one-size-fits-all solution. Rather, inventory thresholds would have to be able to be customized per site, and at least some portions of the inventory management system needed to be blinded from other site personnel.




Prelude Dynamics proposed the client use VISION™, an electronic data capture system, which already has an Inventory Management Module to manage inventory. As the Treatment Dispenser recorded when a patient had received medication or supplies and the amount dispensed, the inventory module would update the inventory on-hand. Prelude proposed to add to VISION™ a feature that would trigger an automatic order when supplies reached a certain threshold, which could be set separately for each site. In addition to VISION™ automatically placing an order, the Treatment Dispenser, study Project Manager and Monitor would be automatically notified via email that the order had been placed.




It is often difficult for busy clinics participating in clinical research studies often to manage the inventory required to be available for the study. Successful inventory management requires a designated person to keep track of how much is on-hand and order additional inventory as necessary. This person usually has other day-to-day responsibilities that make keeping up with this task difficult. If the designated person were to forget or put off the task the enrollment and treatment of subjects could be jeopardized because medication or supplies are not available. Automating this process would greatly reduce the effort involved in participating in the study and would ensure a better outcome.




Prelude staff trained the study staff to utilize VISION™’s existing Inventory Management Module to keep track of inventory as it is dispensed to the patient and logged in the dosing eCRF. The solution included setting the module up to handle the following scenarios:


  • Allow study management to initial inventory sent and site shipping information.
  • Allow initial inventory and future inventory received to be logged and tracked.
  • Aggregate the dispensing information into a summary table.
  • Reconcile the on-hand inventory in real-time.
  • Allow minimum and maximum inventory threshold levels to be set at the site level.
  • Automatically order additional medication and/or supplies when the inventory meets or falls below the minimum threshold, for the difference between the actual amount on-hand and the maximum inventory threshold.
  • Notify the study management personnel at site treatment dispenser that an order has been placed.
  • Manage final reconciliation at the end of the study, allowing the site to enter return shipment information for remaining inventory and study management to reconcile the shipment when received.
  • Provide tracking method for deviations or comments/notes to file when medication is not returned by subject or when medication is missing or lost.
  • Provide ability to track if empty bottles are collected and shipped back or disposed of as required by the sponsor and protocol.
  • Allow site personnel access to certain information, such as inventory received, but not any information that might disclose the treatment group provided to each subject in order to protect study masking during the study, but allow access to all the information upon study completion.


Results & Benefits


As a result of using VISION™, the burden on site personnel to keep track of inventory has been greatly reduced. The sites report that they appreciate the automatic reordering and email notifications of placed orders, adding that it is “such as stress relief to have VISION™ order for them.”


The study Project Manager was able to enter initial inventory ordered and shipped to the site, along with site shipping information, simplifying tracking all inventory information in a central location. She received email notification when the Treatment Dispenser entered the initial receipt of the inventory into the system, confirming its arrival. She was very pleased with the entire module, noting that, “It is wonderful to know that I can relax about whether the sites are keeping up with the inventory and reordering meds and supplies when they are getting low because it happens automatically. There are so many other things I have to keep track of. It is helpful not to have to be burdened by the inventory management.”


The Treatment Dispenser finds it useful view a single table for a full history dispensed medication and/or supplies. He appreciates instant viewing of aggregate dispensed and automatic reconciliation of inventory, and is able to add notes directly on the dispensing form if there is a discrepancy in the amount of medication returned or if there are missing medications or supplies. All these notes are aggregated automatically in a note to file with details about the form and field, who entered the note and when it was entered. This makes it much easier than having to enter all these details manually. He indicated that he was extremely satisfied with the inventory management. He said that keeping up with the inventory and reordering was so much less burdensome and stressful that it had been previously. In fact, the Treatment Dispense indicated he wished all studies used VISION™’s Inventory Management module and thinks everyone should consider using VISION™ for future studies. He said it was intuitive, easy to use, and followed the work flow well. Other treatment dispensers at other sites had similar positive experiences.


Throughout the study, sufficient inventory levels were maintained to be able to enroll all patients eligible for the study who were willing to participate. This gave all study personnel more confidence in their ability to successfully enroll a new subject every time.


VISION™ Feedback Tool Has Been Enhanced to Support Client Approval and Testing Documentation

AUSTIN, TX – March 10, 2016 – Prelude announced today that it has enhanced its feedback tool. Clients use VISION’s feedback tool during the study build process to communicate changes and needs to their Prelude Project Manager. Feedback is integrated into the study and allows users to leave feedback directly on the pertinent field.

When feedback is left, as with all data entered into VISION, there is a full audit trail of who left the feedback and when. The feedback tool tracks the communication between the Sponsor and Prelude related to study design needs.

As expressed by one of our clients, “We appreciate the iterative development study process and relationship we have with Prelude. The feedback tool allows us to quickly note any changes. It keeps track of the changes we have requested, and allows us to have a team of people testing and interacting with the study during the development phase. As the PM in charge of this process, this enhancement allows me to approve the suggested changes before Prelude implements them. And the audit trail allows me to see which of our staff entered the change so I can follow up with them if I have questions prior to approving the change.”

The enhancements include addition of a change approval column and a reviewed column. The change approval column is intended to be used by the project lead to indicate whether the suggested change should or should not be made. This is important because many clients engage teams to collaborate in and test the study build. Each of these team members comes from a different perspective and might make different suggestions based on their experience. Some of the changes suggested might not be needed or might be in conflict with other changes, so this allows the project lead to review and designate each change as desire prior to Prelude’s implementation.

The reviewed column allows clients to better track and review the requested changes. Once the change is made, the Client needs to ensure the change is made as desired. Many clients were tracking this offline on excel sheets because it was an important quality assurance process. Now, they can quickly indicate their review directly in VISION™ which gives them a full audit trail of their approval.

Additionally, the testing documentation provided to clients as a suggested starting point for testing their study has been enhanced. It is now available as a pop-up window rather than a download. This makes it easy to have the testing document beside the study to ensure thorough testing.

Prelude Dynamics is an industry leader at providing innovative software-as-a-service technology solutions for clinical trials across the globe. The company’s flagship product, VISION, offers secure and configurable data capture and information awareness tools for the advancement of human and animal health, compliant with FDA/CVM and EMEA regulations. VISION™ facilitates real-time data collection, querying, cleaning, reporting, and analysis all based on the needs of the researchers. The company was established in 2003 with a goal to speed the study process, improve data quality, and facilitate easy data entry through automation.


Jim Pedzinski – VP of Business Development
jpedzinski[at] – 512-476-5100 ext. 210