ABSTRACT
Objective To describe the reference intervals and their sources of tumor markers in clinical laboratories all over China.And make a comparison of difference between different testing systems.Methods The questionnaires about reference intervals of tumor markers testing were distributed to participants.The information was collected by external quality assessment software system based on website, which including upper and lower limits, sources, validation information and testing systems.The analytes were AFP, CEA, total-PSA, CA125, CA153, CA199, ferritin and free-PSA. The participants were classified according to the testing systems they used.The mean, median, maximum and minimum of each group were calculated using Microsoft Excel 2007.The difference of reference intervals between different testing systems were compared by Kruskal-Wallis test.Results The main source of reference intervals was instructions of testing system manufactures ( 83.1% for mean of 8 ratios ) .The next in sequence were instructions of reagent manufactures(8.4% for mean), National Guide to Clinical Laboratory Procedures (4.6%for mean), determined by their own laboratory(2.0% for mean) and the rest (1.9% for mean). There were 48.0% ( 1 906/3 967 ) of analytes whose reference intervals had been validated.Difference of reference intervals which was with P value of Kruskal-Wallis test with <0.05 was found between different testing system groups except the upper limit of free prostate specific antigen ( PSA ) .Conclusions Most clinical laboratories establish the reference intervals of tumor markers on the basis of instructions of testing system manufactures.The reference intervals among different testing systems have statistically significance.
ABSTRACT
External quality assessment (EQA)as an effective tool for quality control can help clinical laboratories to discover quality problems during testing process and prompt clinical laboratories to improve their testing quality.Samples used for traditional EQA frequently have matrix effects which assign the target value by grouping.Ideal samples for EQA are com-mutable which have the same numeric relationship between different measurement procedures as that expected for patients’ samples.And they can assess accuracy against a reference measurement procedure or a designated comparison method.When analyzing,robust statistical method can be used to reflect the variability of testing results between laboratories more truly. And the evaluation standards should be desirable.If unsatisfactory results appear,we should investigate every aspect of tes-ting process,find the root cause,and take corrective action.On condition that no official EQA scheme is launched for some analytes,it is necessary for us to evaluate the performance of analytes by alternative evaluation procedures.
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Objective To study the internal quality control(IQC)designing procedure of the quantitative immunoassay testing i-tem to provide the most suitable IQC rule for the clinical laboratory immunoassay.Methods 3 quantitative detection items of thy-roxine,cortisol and thyroid stimulating hormone were taken for examples.The coefficient of variation(CV)of the method was ob-tained by the repeatability test for evaluating the methodological imprecision.Inaccuracy(bias)was obtained by the methods com-parison.The accuracy of the method was evaluated.Then the most suitable IQC rule for each quantitative detection item was select-ed by plotting the location of the operating point on the normalized operational process specifications(OPSpecs)chart according to CV and bias.Results Two multirule methods of 1 3s/(2of3)2s/R4s/3 1s/6 x and 1 3s/(2of3)2s/R4s/3 1s were identified when the oper-ating point was plotted on the normalized OPSpecs chart for N =6 and 90% analytical quality assurance(AQA)at the thyroxine de-cisive level of 0.064 4 mmol/L.When the cortisol decisive level was 0.735 μmol/L,the normalized OPSpecs chart for N =3 with 90%AQA showed the three solutions of 1 3s/(2of3)2s/R4s/3 1s ,1 2 .5s ,and 1 3s/(2of3)2s/R4s as for thyroid stimulating hormone,3 1s/2 2s/R4s/41s multirole procedure was the best choice for N =4,50%AQA at the upper control level,and the N =2 chart with 50%AQA showed a multirole procedure with 1 3s/2 2s/R4s at the lower control level.Conclusion The suitable internal quality control de-signing procedure of the quantitative immunoassay testing item can be selected by using the OPSpecs chart.
ABSTRACT
Key factors for interpreting proficiency testing (PT)/external quality assessment (EQA) results are knowledge of the commutability of the samples used and the process used for target value assignment.A commutable PT/EQA sample,which would be seen as patients' samples,has the agreement of results among different measurement procedures and demonstrates the same numeric relationship.The value assignment for the sample can be done by using of a reference measurement procedure.Its results can be used to assess the accuracy against a reference measurement procedure or a designated comparison method.Noncommutable PT/EQA samples frequently have a matrix-related bias of unknown magnitude,and can't give meaningful information about the relationship of results for patients' samples among different measurement procedures.Its results must be compared to the peer group mean or the median of results from participants who use measurement procedures that are expected to have the same or very similar matrixrelated bias.
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Objective To study the management of enterostomy in children.Methods The clinical data of 425 cases of enterostomy in children were analyzed retrospectively.Results The primary diseases of 425 cases underwent enterostomy included:intestinal perforation(119 cases),intestinal necrosis(36 cases),necrotizing enterocolitis(45 cases),congenital megacolon(61 cases),congenital anal atresia with rectourethral fistula(86 cases),and congenital anal atresia with rectovaginal fistula(78 cases).Among the 425 cases,159 cases underwent small bowel enterostomy and 266 cases had colostomy;single-stoma enterostomy was done in 225 cases,and double-stoma enterostomy in 197 cases.Follow-up was acquired in 389 patients,and all the stomas were closed successfully.The closure time of small bovvel enterostomy was 1-3 month(ayerage 1.87 months)later,and of colostomy was 3-12 month(averag 4.95 months)later.Conclusions When an enterostomy is to be adopted in pediatric surgery,a suitable time and enterostomal location should be chosen according to the state of illness.The timing of enterostomy closure is also very important.