Effects of non-analytical factors on the quality of laboratory results.

The quality of clinical laboratory measurement is comprised of 2 phases, the analytical and non-analytical phases. Nowadays, a well established quality control system has been applied. However, the non-analytical phase is a state of the art that must be paid attention to. We studied the non-analytical (pre- and post-) factors. A questionnaire was distributed to 298 hospital laboratories whom participated in the External Quality Assessment Scheme in Clinical Chemistry (EQAC) program of Faculty of Medical Technology, Mahidol University. The respondent rate was 71%. Most of the responder was female with a bachelor degree in medical technology or equivalent, who was the chief of the laboratory. Results shows that patient preparation, patient identification, specimen acquisition, specimen handling, and documentary system (specimen recording and result reporting) were important consideration factors. The turnaround time was also a main issue. Verification of test results was an important process too. Finally, as a good laboratory practice, one must has the strategies to detect and eliminate the non-analytical errors.

Reference value for urinary deoxypyridinoline as a specific marker for measuring bone resorption in Thais.

In the next century, the increasing number of elderly and rising healthcare costs will bring with it metabolic bone problems, particularly osteoporosis. Deoxypyridinoline: Dpd in urine is a sensitive and specific marker for screening and monitoring of bone resorption in a variety of diseases affecting bone turnover and in risk groups especially in the postmenopause. The reference value among aging (21-60 years) of a healthy well defined group was studied by collecting the urine between 700-1000 hours and using the ELISA technique to determine the level of Dpd. The reference value of Dpd in 113 males and 298 females 1.3-6.5 and 1.5-6.9 nm Dpd/nm Creatinine respectively. The level of Dpd in females was significantly higher than in males at p < 0.028. However, the average value of deoxypyridinoline in postmenopause was higher than premenopause but not different at p = 0.05. There are many factors which influence the results so the overall reference value is only a guideline for screening in bone resorption.