QUALITY CONTROL
The BPROAD Manual of Procedures (MOP) includes all the details of trial procedures. We use the BPROAD MOP to train study investigators and staff and as a reference during trial preparation and conduct. Key study procedures are standardized, such as standard forms, equipment, and procedures in the study centers for BP measurement, the use of a central laboratory, ECG reading center, and outcome assessment committee at the Coordinating Center.Training of staff is important to standardize procedures and assure data quality. We organize up to 10 training sessions at different regions across mainland China. Staff members from study centers within the regions are convened in a single, centrally administered face‐to‐face training session. We conduct a second face‐to‐face training at individual study center before screening of the first participant in that study center. Training videos are available for study staff to watch at any time. In addition, the Coordinating Center organizes yearly refresher training sessions to all study centers.Data are collected using an electronic data capture system. The Coordinating Center is responsible for data monitoring and query reports. Study center staff is responsible for reviewing and resolving the data queries in a timely manner. Routine (eg, monthly) quality control reports will be developed by the Coordinating Center and will be distributed to all study centers on measures of process, impact, and outcomes.Study samples are collected and centrifuged, aliquoted, and stored at −80 degrees before shipment in dry ice to the central laboratory within 3 months after collection. The central laboratory participates in the American College of Pathologists' Laboratory Accreditation Program and is reviewed and accredited on a regular basis. Samples are measured according to standard procedures and quality control requirements to ensure high‐quality measurement data. Samples that do not undergo measurement are stored at −80 degrees in the Coordinating Center for future research.