A Critical Appraisal of Current Practice in the Detection, Analysis, and Reporting

To assess current practice in the detection, analysis, and reporting of cryoglobulins, a questionnaire was sent to 140 laboratories. Only 36 % of laboratories used standard procedures (tube preheating, transport in container, and sedimentation and/or centrifugation at 37 °C) to ensure that the temperature did not drop be-low 37 °C until after serum separation. Time periods allowed for cryoprecipitation at 4 °Cvaried from12h to 9 days, with 30 % of laboratories allowing precipitation for 3days. After cryoprecipitation, 81%of laboratories res-olubilized the cryoprecipitate at 37 °C, and 77 % further immunotyped the cryoprecipitate. After analysis, 5% referred the sample for confirmation, 58 % provided a nonquantitative report, and 37 % reported the cryoglob-ulin concentration in the cryoprecipitate as cryocrit, tota