Quality control of biochemical data in the Multiple Risk Factor Intervention Trial: Central Laboratory.

The acquisition of quality biochemical data in the MRFIT was enhanced by writing detailed protocols, instituting strict rules for collecting and shipping specimens, setting high goals for analytical performance, using reliable means to transfer data, employing dedicated and competent analysts, and having a director of the Central Laboratory who believed in and enforced an effective quality control system. A Laboratory Quality Control Subcommittee was formed to work with this director in solving laboratory problems, with the Coordinating Center in conducting appropriate monitoring, with the Quality Control Committee in documenting the quality of data and investigating any laboratory problems, and with other committees of the directors and Program Office in responding to any questions raised about laboratory aspects of the trial. All of these efforts culminated in reliable biochemical data.