Annual Report on External Quality Assessment in Therapeutic Drug Monitoring and Drug of Abuse in Korea (2007) / 임상검사와정도관리

ABSTRACT

Two trials of external quality assessment for Therapeutic Drug Monitoring (TDM) subcommittee of Korean Association of Quality Assurance for Clinical Laboratory (KAQACL) were performed in 2007. Number of participating laboratories were increased to 109, by 5.63% increase comparing with the previous year. Response rates reached 98.7% for both trials slightly lower than that of the previous year. Two kinds of control materials were requested to be tested in each trial so that each institution could know the possible systematic error. In both trials, 20 test items were responded at least from one laboratory. The average drug item was 6.3 per institution, which was decreased slightly from 6.8 in recent 5 years. The most common test items were valproic acid, digoxin, carbamazepine, theophylline, phenytoin, and phenobarbital which were peformed in more than 55% of the participating laboratories, followed by cyclosporine, vancomycin, lithium, tacrolimus, methotrexate, amikacin, gentamicin, salicylate, tobramycin, acetaminophen, primidone, free phenytoin, and amitryptyline. The inter-laboratory coefficients of variations showed simliar tendency comparing with those of the previous years. We started the proficiency test for drug of abuse from 2007 and got the response from 13 and 17 laboratories in the 1st and 2nd trial, respectively. Average drug items were 3.4 for the 2nd trial. We found the relatively good performances as we got the correct answers from all laboratories except 4 for each one mistake. In conclusion, the TDM external quality assessment of 2007 showed grossly similar pattern comparing with those of previous year and drug of abuse proficiency testing showed a relatively good performance.