Clinical trials: considerations for designing and building an electronic data capture (EDC) system

Part 1: with users in mind

In clinical trials, electronic data capture (EDC) systems are widely used to collect data such as patient assessments, patient outcomes, laboratory test results, medication use, adverse events, etc. The EDC system provides a convenient method for clinical trial sites to enter the data from their patients, to track patient visits, and to answer questions about the data. A well-designed EDC system is simple and intuitive to use, which is essential to ensure data integrity and quality by reducing entry errors. Within the EDC system, the data are arranged on various case report forms (CRFs). Each CRF corresponds with a patient visit or a type of information (e.g., medical history or medication use).

There are several challenges encountered in designing CRFs, including consistency, collection of specific data and user-friendliness. Poorly built EDC systems can create an increased potential for data entry errors, causing delays in completing CRFs. The ability of an EDC system to minimize data entry time and reduce errors can improve the quality of data, which in turn may reduce the entire study timeline. Hence, it is important to plan carefully and give attention to minute details prior to building the EDC system. This blog post presents some factors to consider while designing and building an EDC system that will provide a positive experience for the user.

CRF Design – Keep it Simple

The primary goal of a CRF is to collect complete and accurate data that are directly related to your research question while avoiding ambiguity and redundancy. This gets at the issue of collecting data you “need to know” versus data that are “nice to know.”  Ideally, your CRF will be designed to collect only information that helps answer your research question without collecting extraneous data that simply take extra time to collect and verify, but provide little added value.  A 2014 survey by the Medical Device Innovation Consortium of 22 pivotal clinical studies revealed that only about 57% of data points captured in CRFs were ultimately used in regulatory submissions.  The rest simply added time and cost to collect and verify.

When designing CRFs, it is critical to keep each form short. Long forms can be confusing and tedious to users.  If scrolling is required, there is a possibility that the user may not see everything on the page. Consistent design from form to form and study to study is a key aspect for structuring CRFs as it can reduce the number of data entry errors. Consistent design principles can help the user enter data with ease since the design will be familiar to them if they work on multiple trials within the same EDC system.

Easy Navigation

One of the keys to effective EDC building is utilizing a design that is easy to learn and navigate. Apart from the CRFs, an EDC system’s framework itself should be clear and sufficiently succinct that it can be intuitively understood. Rather than a labyrinth of complicated routes that require several clicks through menus and sub-menus which leaves users confused and frustrated, the system organization should enable the user to quickly and simply find what he or she is looking for. Additionally, the EDC system should be helpful without being intrusive. In other words, the navigation system should provide useful information to help the user navigate through the data forms without overly complicating the process. For example, there should be some indicator of where one is within the CRF and a simple method to return to a previous location.

Efficient Workflow

The efficiency of an EDC system is directly related to its design. An effective framework enables users to perform data entry in less time with fewer errors. A good way to prevent erroneous data from being entered in the database and to minimize the need for subsequent queries is the judicious use of edit checks.  Edit checks are automated triggers within the system that ensure the data entered are complete and within the proper range. Edit checks are an important part of the workflow, and should be used sensibly within the EDC system.

Questioning of entered data values based on a defined acceptable range is one good way to ensure data entering the database are correct. Unfortunately, hard edit checks that keep the user from advancing to the next field or page, unless indicated criteria are met, are frequently overused. Hard edit checks enforce restrictive rules that prevent the user from saving the form.  When this happens, users become frustrated and may enter incorrect data that meets the criteria just to be able to proceed. Overrides should be available to permit data entry to continue if the value can be justified. One should consider using edit checks that allow the user to continue after they clarify the entered data by means of a remark or comment. Another important point is to program certain fields to automatically calculate a value from the data already entered (e.g., BMI calculation from height and weight). This will preclude the user from performing manual calculations, which could increase the likelihood of inaccurate and inconsistent data.

Built-in Reports and E-mail Notifications

Good EDC systems include at least a rudimentary set of reports, which may be used by the clinical site staff to track various aspects of site activities such as patient enrollment, outstanding data, or follow-up visits. Additional sophisticated, configurable reports are desirable for robust study conduct, such as adverse event reports, action item tracking, etc. As with building the EDC system, the design of reports should be well-considered and planned prior to the start of the study. Well-designed reports can support compliance by directly comparing the trial’s requirements with the site’s performance.  For example, by creating custom reports, site staff can analyze which CRFs have outstanding data or queries that can be corrected during the trial.

Additionally, the EDC system should include CRFs that are programmed to provide automatic notifications to the sponsor for events of particular interest such as Serious Adverse Events or the need to order product when site inventory is low. These notifications help the site staff to fulfill the requirements of timely notification without having to complete paper forms and scanning/faxing them to the sponsor.  This rapid response allows additional time for site staff to provide any necessary follow-up while still meeting reporting deadlines.

A well-designed EDC system is efficient for users, which saves them time and frustration. It provides tools to help them manage the clinical study and enter data in an intuitive way, which leads to more complete and accurate data. Over time, the ease of use can lead to users prioritizing your project over others, which leads to faster enrollment and more timely data submission. And of course faster studies with reliable data can have tremendous financial and productivity benefits for your company. As seasoned EDC designers at MED Institute, we can use time-tested best practices to help you navigate EDC requirements to accelerate your study.

If you have any questions about how to design more efficient, cost-effective clinical trials, please call us at 855.463.1633 or visit our website


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