Once data have been screened for typographical errors, the data can be validated to check for logical errors. An example is a check of the subject's date of birth to ensure that they are within the inclusion criteria for the study. These errors are raised for review to determine if there are errors in the data or if clarifications from the investigator are required. Another function that the CDMS can perform is the coding of data. Currently, the coding is generally centered around two areas —
adverse event terms and
medication names. With the variance on the number of references that can be made for
adverse event terms or
medication names, standard dictionaries of these terms can be loaded into the CDMS. The data items containing the
adverse event terms or
medication names can be linked to one of these dictionaries. The system can check the data in the CDMS and compare them to the dictionaries. Items that do not match can be flagged for further checking. Some systems allow for the storage of synonyms to allow the system to match common abbreviations and map them to the correct term. As an example, ASA (
acetylsalicylic acid) could be mapped to
aspirin, a common notation. Popular
adverse event dictionaries are
MedDRA and
WHOART and popular Medication dictionaries are
COSTART and
WHO Drug Dictionary. At the end of the clinical trial the
data set in the CDMS is extracted and provided to statisticians for further analysis. The analysed data are compiled into
clinical study report and sent to the regulatory authorities for approval. Most of the drug manufacturing companies are using Web-based systems for capturing, managing and reporting clinical data. This not only helps them in faster and more efficient data capture, but also speeds up the process of drug development. In such systems, studies can be set up for each drug trial. In-built edit checks help in removing erroneous data. The system can also be connected to other external systems. For example, RAVE can be connected to an IVRS (
Interactive Voice Response System) facility to capture data through direct telephonic interviews of patients. Although IRT (Interactive Response Technology) systems (IVRS/IWRS) are most commonly associated to the enrollment of a patient in a study thus the system defining the arm of the treatment that the patient will take and the treatment kit numbers allocated to this arm (if applicable). Besides rather expensive commercial solutions, there are more and more open source clinical data management systems available on the market. CDMS implementations are required to comply with 21 CFR Part 11 federal regulations to be used for FDA registered drug trials. Part 11 requirements include audit trails, electronic signatures, and overall system validation. == See also ==