The traditional way to do the clinical trial data management is to use the paper based case report forms (CRFs). The blank paper CRFs are distributed to the investigator sites. The investigator or study coordinator fills out the CRFs. CRFs will then be monitored and collected from the investigator sites. CRFs will subsequently be handled by a centralized group - data management group where the activities include the clinical database building, data entry, data cleaning, data clarification,...
The industry trend has been gradually moving away from the paper-based CRFs and moving toward to the electronic data capture (EDC). In EDC world, the database was built prior to the study start (significant longer leading time prior to the study study is needed) . The data will be directly entered into the database by the investigator site (investigator or study coordinator). EDC has been touted by many vendors as the preferred way for conducting clinical trials: getting the data fast, saving timeline, saving cost, minimizing data transcription errors... While this is generally true, it is not universal.
In some situations, the trial using the traditional paper-based CRFs is a better way than EDC. For example, in a clinical trial for a rare disease, there are many investigator sites and each site may only enroll very few subjects or not enroll any subject. The EDC will not be an efficient way in data collection. Many site staff will be trained on EDC and never have chance to enroll any patient into the study and never have a chance to use EDC. When a site finally has a chance to enroll a subject, the initial training on using EDC may be a distant memory.
The EDC trial is not always cheap. With EDC trial, significant cost could be spent on the EDC system hosting and EDC system help desk support. Imagining a slow enrollment trial running for 7-8 years, the cost for hosting EDC system and providing the help desk support will be too much comparing to a paper-based study.
While EDC is a trend, the adoption of EDC is not universal. In some situations, the traditional paper CRFs may be better.