Sigma Metrics Across the Total Testing Process.

Laboratory quality control has been developed for several decades to ensure patients' safety, from a statistical quality control focus on the analytical phase to total laboratory processes. The sigma concept provides a convenient way to quantify the number of errors in extra-analytical and analytical phases through the defect per million and sigma metric equation. Participation in a sigma verification program can be a convenient way to monitor analytical performance continuous quality improvement. Improvement of sigma-scale performance has been shown from our data. New tools and techniques for integration are needed.

Evaluation of the analytical performance of the nova StatSensor creatinine meter for blood testing.

BACKGROUND AND OBJECTIVE: For reliability of laboratory results, all methods, instruments, and reagents should be evaluated The Nova StatSensor creatinine meter is a hand-held device for determination of creatinine concentration in the whole blood Therefore, the device has to be validated or verified before performing. MATERIAL AND METHOD: Observational analysis method with cross sectional design was used in this evaluation. The commercial reagents and coded samples were prepared for linearity, precision, accuracy, and interference studies. RESULTS: The linear measurement range of 1.3 to 9.5 mg/dL was verified with the recovery results between 91.6 to 105.0%. Total imprecision demonstrated by coefficient of variation (CV) was 6.4 to 8.9 CV%. Linear regression was y = 0.946x + 0.103, r = 0.992, r2 = 0.984. The bias was calculated from our data using regression equation. Our results demonstrated the accuracy was acceptable. Glucose level of 200 mg/dL and 400 mg/dL created the high difference between baseline creatinine (1.2 mg/dL and 2.8 mg/dL) and creatinine measured in the presence of interference was 25.0%, 16.7%, 14.3%, and 19.7% respectively. CONCLUSION: Our results demonstrated that the device provides reliable creatinine measurement and could be used in point-of-care testing. Use of this device in diabetic patients with high glucose level of > or = 200 mg/dL is not recommended

Prevalence of BRCA1 expression in epithelial ovarian cancer: immunohistochemical study.

The 99 formalin fxed paraffin-embedded ovarian tissue specimens of Epithelial Ovarian Cancer (EOC) patients treated at the Gynecologic Oncology Unit, King Chulalongkorn Memorial Hospital between January 1, 1996 and December 31, 1999, were immuno-stained with BRCA antibody using the immunohistochemical method. According to the criteria for BRCA1 immunohistochemical evaluation (neoplastic nuclear staining more than 10%), 12 (12.1%) of the 99 specimens showed positive BRCA1 expression. No associated statistical significance between clinicopathological variables and BRCA expression was detected. Survival analysis was performed in 87 patients who were followed-up for more than 6 months and recent status were available. During a median follow-up of 43 months, median survival time was 46 months (range 6-84 months). No association between BRCA1 expression and survival outcomes was found (Disease free survival and overall survival) in the presented patients.

Determination of reference intervals of HbA1C (DCCT/NGSP) and HbA1C (IFCC) in adults.

OBJECTIVE: To establish HbA1C reference intervals according to DCCT/NGSP (HbA1C DCCT/NGSP) and IFCC (HbA1C IFCC) in adults. STUDY DESIGN: The study was a descriptive study. MATERIAL AND METHOD: The study was done in 144 subjects, with 99 males and 45 females, aged between 19 to 78 years old. All subjects had normal vital signs, physical examination, chest X-ray. Subjects who had hyperglycemia, renal problem, liver problem, anemia, and/or hemoglobinopathy were excluded from the present study. RESULTS: Reference intervals of HbA1C (DCCT/NGSP) is 5.47% (4.79-6.15) and HbA1C (IFCC) is 3.66% (2.88-4.44). The authors also found very high correlation between HbA1C (DCCT/NGSP) and HbA1C (IFCC) of total, male, female, < 35 years old, and > or = 35 years old, r = 0.9995, 09997, 0.9992, 0.9988, and 0.9999, respectively. CONCLUSION: The authors found that HbA1C (DCCT/NGSP) and HbA1C (IFCC) are not affected by sex but are influenced significantly by age group. Since HbA1C (IFCC) will be widely used in routine diabetes management, the authors recommend all laboratories provide the results of HbA1C in both DCCT/NGSP and IFCC methods during this interim period.

Annual laboratory checkup: early signs of health problems in young and middle-age adults.

The objective of this descriptive study was to review the usefulness and relevance of the present parameters provided in an annual laboratory health checkup program. Three hundred sixty-four volunteers were randomly selected, composed of 141 males and 223 females age 15 to 81 years old. Samples from all the volunteers were analyzed for CBC, FBG, BUN, Cr, uric acid, Chol, HDLc, Tg, AST, ALT, ALP, UA and stool examination. More than half the young adults (67.7%, 63 of 93) had abnormal laboratory results. This was higher than in the middle-age group (56.8%, 154 of 271).

Reference value for C-reactive protein and its distribution pattern in thai adults.

BACKGROUND: To set a reference value for high-sensitivity C-reactive protein (hs-CRP) in a healthy Thai population and study the effect of time, gender and age on that value. METHODS AND RESULTS: Three hundred and sixty-four subjects, aged between 18 and 74 years, comprising 185 men and 279 women, were studied. Another 10 healthy subjects, aged between 18 and 54 years, were recruited for the study of circadian variation in hs-CRP over the days of the week and the months of a year. The reference value for the Thai adults in the present study was 1.8 mg/L, range 0.2-7.9 mg/L. There was no significant difference in the hs-CRP concentration because of region, time, gender or age (p>0.05), nor was the value affected by time. CONCLUSION: The determination of hs-CRP can be performed at any time and the hs-CRP value determined by this study can be used as the reference for Thai adults.

Evaluation of calculated low-density lipoprotein against a direct assay.

OBJECTIVES: To evalate compare the calculated LDL determined by the Friedewald formula when Tg < 200 mg/dL, 200-399 mg/dL, and > or =400 mg/dL against a direct method. MATERIAL AND METHOD: Samples from 202 participants (122 males, 80 females, aged 20-87 years old) were determined for cholesterol, triglyceride (Tg), high-density lipoprotein (HDL), and low-density lipoprotein (LDL) at Department of Laboratory Medicine, King Chulalongkorn Memorial Hospital (KCMH). LDL was determined by Friedewald formula and a direct method. RESULTS: Intra-assay and inter-assay precisions at Tg <200 mg/dL, 200-399 mg/dL, > or =400 mg/dL of calculated LDL and direct LDL were 4.80%, 3.29%, 20.37%, 4.86, 8.42%, 8.32%, 2.11%, 1.79%, 3.99%, 2.36%, 2.41% and 6.16%, respectively. The mean absolute biases calculated for calculated LDL against direct LDL at Tg <200 mg/dL, 200-399 mg/dL, > or =400 mg/dL and for total samples were 4.70%, 11.73%, 63.65%, and 7.46%, respectively. Linear regression analysis for calculated LDL vs direct LDL for total samples and grouped as Tg <200 mg/dL, 200-399 mg/dL, and > or =400 mg/dL were 0.9190, 0.9796, 0.9440, and 0.7910, respectively. Intraclass correlation coefficient (ICC) at 95% confidence interval of calculated LDL against direct LDL at Tg <200 mg/dL, 200-399 mg/dL, > or =400 mg/dL and for total samples were 0.963, 0.930, 0.767, and 0.889, respectively. CONCLUSION: The present data suggested that direct LDL is superior over calculated LDL in terms of precision and accuracy. The present study supported that at Tg > or =400 mg/dL calculated LDL should not be used and the traditional cutoff of Tg <400 mg/dL for using Friedewald formula should be revised. In addition, regarding patient convenience, financial reason, and precision and accuracy of analytical method, direct LDL is recommended when Tg > or =200 mg/dL.

Cost analysis of laboratory tests: a study of the Central Laboratory of King Chulalongkorn Memorial Hospital.

OBJECTIVES: To present cost analysis on laboratory management of laboratory tests provided by the Central Laboratory of King Chulalongkorn Memorial Hospital (KCMH). MATERIAL AND METHOD: The expenditure and income of the laboratory were studied using a descriptive design. RESULTS: The Central Laboratory provided routine hematology, urinalysis, and chemistry tests, and performed 2,157,275 tests in year 2002. The expenditure of the Central Laboratory was 32,094,960.24 baht, while the income was 97,393,244.40 baht. The average calculated profitability ratio for all parameters was 3.03. CONCLUSION: The authors concluded that the Central Laboratory is a good Revenue Producing Cost Center (RPCC) for the hospital. To improve the laboratory efficiency, the data needed for laboratory management should be easily available to the laboratory manager. In addition, the authors strongly suggest that the organization structure and the data management system of the hospital and the faculty should be simplified for future management. In addition, all laboratories should perform their own cost analysis.

Relationship between progesterone receptor level in endometrium and bleeding pattern in depot medroxyprogesterone acetate users.

Bleeding disturbance is the major reason for discontinuation among depot medroxyprogesterone acetate (DMPA) users. However, the causes of progestin-induced bleeding are not well understood. The aim of the study was to examine the correlation between the occurrence of uterine bleeding and progesterone receptor (PR) levels in the endometrium. Forty-five matched pairs of age and body mass index in DMPA users with bleeding and amenorrhea were studied. The endometrial PR levels were evaluated. The PR score was assessed semi-quantitatively. Forty-two subject pairs met the criteria. There was no difference in serum estradiol and progesterone levels between the groups. No correlation between the number of bleeding days and PR score nor between the number of bleeding days and serum estradiol and progesterone level was detected. The stromal PR score in DMPA subjects with amenorrhea was significantly higher than those with bleeding (p < 0.05). By contrast, the PR score in glandular endometrium was not significantly different between the groups (p > 0.05). In conclusion, after a second dose of DMPA, subjects with amenorrhea had a higher stromal PR score than those with uterine bleeding.

Evaluation of the Sysmex UF-100 automated urinalysis analyzer and comparative study with JCCLS reference method.

Microscopic urine sediment analysis has been accepted as the mainstay test for examining urine cells and particles. Although it provides essential information for clinicians about disease states in the patients, it is a high-volume and laborious procedure. Therefore, an automated analyzer was developed recently and has just been introduced to Thailand. In this study, the authors evaluated the analytical performance of this new automated urine analyze. Also a comparative study was performed between the UF-100 test results and those of JCCLS reference method. In evaluation of the Sysmex UF-100 automated urinalysis analyzer, both precision and linearity studies were performed. Between-run CVs for RBCs (mean = 182.46/microl), WBCs (mean = 193.37/microl), ECs (mean = 70.05/microl) and casts (mean = 12.21/microl) were 7.74 per cent, 5.52 per cent, 21.32 per cent and 7.69 per cent, respectively. Concerning the within-run CVs for the RBC analysis, the CV ranged from 16.28 per cent for low numbers of RBCs (35.67/microl) to 2.93 per cent at RBC concentrations (712.13/microl). Concerning within-run precision for the WBC analysis, the CV ranged from 22.31 per cent for low numbers of WBCs (WBCs 12.53/microl) to 2.07 per cent at a WBC count of 211.01/microl. Within-run precision ranged from 11.36 per cent at 24.99 ECs/microl to 6.18 per cent at 53.08 ECs/microl. Within-run precision for casts varied from 35 per cent for samples with 1.33 casts/microl to 12.38 per cent for samples with 4927.35 casts/microl. From the comparative study, good agreements (p < 0.05) were obtained between UF-100 and JCCLS reference method for RBCs counts (p = 0.000, r = 0.974) and WBCs counts (p = 0.000, r = 0.913). However, fair agreement (p > 0.05) was obtained between UF-100 and JCCLS reference method for ECs counts (p = 0.017, r = 0.212) and casts counts (p = 0.624, r = 0.044). In conclusion, the UF-100 analyzer is a new useful analyzer although it cannot be a substitute for microscopic sediment examination.

Situation of laboratory service and instruments in Thailand: a descriptive study from questionnaires.

Laboratory instruments are one of the main items in laboratory investment. To establish data for the situation of laboratory service and instruments in Thailand, questionnaires were randomly sent to one hundred and twenty laboratories. Sixty-three filled questionnaires from eleven university and affiliated hospitals, thirty-four government hospitals, and eighteen private hospital laboratories were sent back to the authors to be analyzed. Only the number of samples and instruments used during office hours were analyzed in this study by descriptive method. From the data it was found that the average number of personnel and tests of the university and affiliated hospital laboratories was the highest. To analyze the efficiency of the instruments used in the laboratories, the authors compared the average service number of samples or tests to the average number of samples or tests that was calculated from the instruments. The ratio of the average number of samples or tests that were calculated from the instruments and the average service number of samples or tests for chemistry and CBC were 2.13, 3.41, 5.24 and 2.33, 2.76, 3.71 in university and affiliated hospital laboratories, government hospital laboratories, and the private hospital laboratories, respectively. From the data, it was concluded that the instrument situation in laboratories of the university and affiliated hospitals was more appropriate than government hospital and private hospital laboratories. To improve the efficiency of using laboratory instruments, more concern must be given to the management of laboratory instruments and cooperation between hospitals could increase the efficiency of the instrument investment.