analytical errors in phlebotomy

was related to the incorrect order of drawing [11]. Phlebotomies observed during the study were mainly performed by nurses. Increased Patient Satisfaction and a Reduction in Pre-Analytical Errors Lund F, Petersen PH, Fraser CG, Soletormos G. Different percentages of false-positive results obtained using five methods for the calculation of reference change values based on simulated normal and ln-normal distributions of data. This site needs JavaScript to work properly. Clotted samples and platelet clumps were seen in 1% of EDTA tubes. Consent was obtained by all participants in this study. Gravetter FJ, Wallnau LB, editors. also published that the importance of continued education and training and monitoring and evaluating the hemolysis rate is crucial [19]. For instance, it could be easy to adequately size the study when the enrolment concerns subjects under oral anticoagulant therapy with INR between 2 and 3, but the situation could markedly change at higher values of INR (38, 43). What outlined above can be nothing but a slow process of growth that demands collective awareness and positive disposition to achieve maturity. The temperature of the centrifuge was measured by the external thermometer. Rejection rates were calculated by the total number of the tubes that were accepted during the dedicated time interval with the following formula: number of rejected samples/total numbers of samples 100. Patient Prefer Adherence. Challenges in Preanalytical Phase of Laboratory Medicine: Rate of Blood Bilic-Zulle L. Comparison of methods: Passing and Bablok regression. The effect of outliers on the relative power of parametric and nonparametric statistical tests. Atay A, Demir L, Cuhadar S, et al. Causes and impact of specimen rejection in a clinical chemistry phlebotomy, preanalytical phase, statistical data analysis, methods. Predictable and avoidable human errors in phlebotomy area - an exclusive analysis from a tertiary health care system blood bank Transfus Med . It is estimated that a majority of all laboratory medicine errors are errors that occur during the preanalytical phase of the laboratory testing cycle. Maximizing the clinical laboratory quality process is gaining increasing importance, and identifying preanalytical errors correctly is becoming critical at each step of this phase. The number of observations according to the departments is shown in Table Table11. Then, substituting for the adjusted testwise in Eq.2.1, it is possible to obtain the deflated experimentwise . Context 1 . While a significant decrease in laboratory errors, particularly analytical errors, has been achieved in last decades, laboratory services are not as safe as they should be and we should not become complacent. Information-seeking behavior and the use of online resources: a snapshot of current health sciences faculty. To maintain analyte value/ stop breakdown Examples of diurnal variation posture, activity, eating, daylight/ darkness, awake/ asleep What is the resting metabolic state of the body when it is at rest and fasting? For instance, one may plan to investigate the rate of pseudohyperkalemia due to needle bore size, and simultaneously investigating the effect of age (random effect), MCV (random effect) and gender (fixed effect) of the subjects adding the appropriate terms. Presentation Presenter Recalling what stated earlier on statistical power, it is virtually impossible to achieve a homogeneous sensitivity for different statistical procedures at the same sample size (50-52). As far as pre-analytics is a major concern in current laboratory medicine and an issue for practitioners and researchers, this field of investigation should be fostered in order to produce evidences for best practice (5, 6). Lippi G, Salvagno GL, Montagnana M, Franchini M, Guidi GC. The list of rejection criteria referred to in this study is given in Table Table22. Abstract. Strategies to avoid these errors include the implementation and enforcement of specific . The method was devised to estimate at-a-glance, by the scatter plot of individual differences between paired observations, the 95% limits of agreement using the 1.96 standard deviation interval around the average bias (87-89). The tube storage conditions, identification of the patient, labeling, disinfection procedures, venipuncture procedures, and safety rules with selected items were checked according to the EFLM WG-PRE Phlebotomy Collection Checklist recommendations for blood collection [11]. Int J Nephrol 2011;2011:759749. Influence of a regular, standardized meal on clinical chemistry analytes. Unauthorized use of these marks is strictly prohibited. When we completed to review the papers, that body of publications looked like highly heterogeneous with some redundancies within the statistical framework. All three phases of the TTP can be dealt with separately, as the analytical errors account for <10% of all errors, and the preanalytical errors account for up to 70% of all laboratory errors [ 6, 7 ]. In pre-analytical investigations, the two kinds of effects are always combined, because planned factors are applied to a random set of individuals (28, 69). the contents by NLM or the National Institutes of Health. Lillo R, Salinas M, Lopez-Garrigos M, Naranjo-Santana Y, Gutirrez M, Marn MD, Miralles M, Uris J. Petrides AK, Bixho I, Goonan EM, Bates DW, Shaykevich S, Lipsitz SR, Landman AB, Tanasijevic MJ, Melanson SE. The site is secure. Therefore, although statistically significant, no clinical significance was produced by the alternative collection procedure. The 70% claim: what is the evidence base? The https:// ensures that you are connecting to the Guidelines for reporting medical research: A critical appraisal. The fill volume error and hemolysis error rates were higher in the observation period except for the clotted sample error. Did the collector clean the venipuncture site? Lippi G, Banfi G, Church S, Cornes M, De Carli G, Grankvist K, et al. Did the collector appropriately sanitize hands? Falagas ME, Pitsouni EI, Malietzis GA, Pappas G. Comparison of PubMed, Scopus, Web of Science, and Google Scholar: strengths and weaknesses. Adopt a standard procedure if available to investigate a pre-analytical factor, or detail it if there is none available. The data pertaining to the number of patients, tests, and rejection rates were obtained from the laboratory information system (LIS) for the one-week and the one-year period and compared with the observational data. Lastly, in 2/36 (0.06), along with Bland-Altman analysis, the bias was estimated through Passing-Bablok regression with 95% confidence intervals (21, 41). Malden, MA: Blackwell Science;2001. p. 817. In another study, they mostly observed the fill volume error type [8]. Changing expectations: Do journals drive methodological changes? We also measured patient wait time and assessed patient satisfaction using a 5-question survey. We found that the largest part of studies had a cohort of healthy volunteers (22/36) or outpatients (11/36), with the former group showing a significantly smaller median sample size (N = 20, IQR: 17.5-30 and N = 88, IQR: 54.5-220.5 respectively, P < 0.001). eCollection 2022. Short-term venous stasis influences routine coagulation testing. All content published within Cureus is intended only for educational, research and reference purposes. Similar to our results, the most correct step of the phlebotomy was the venipuncture site collection [11]. Analytical errors Spurious results Introduction Patients with coagulation disorders may either bleed or form thromboses. Jean Meneses-Claud io 1, *, Pamela Bautista-Sosa 1, Judith Munive-Dionisio 1, Anny Catacora-Pilares 1, Rosa Per ez- 4th ed. Specimen Collection Module vs No Specimen Collection Module. 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Indeed, apart from the provision with qualitatively appropriate supplies that depends on the healthcare services choice, there are no other means than the operators skills and compliance with standard procedures to ensure the adequate sample quality (4). As they both depend on the underlying assumption of statistical normality (same probability of getting an equally large positive or negative variation), they can be reformulated using a robust non parametric model in order to better resemble the structure of data and gain the appropriate sensitivity (84, 85). Prothrombin Time (PT) mixing test requested before PT test) could only be monitored from LIS and was seen by 0.11% and 0.01% in one-week and one-year LIS periods. 1Department of Human Physiology and Pharmacology, University of Rome Sapienza, Rome, Italy, 2Laboratory Medicine Department, Tor Vergata University Hospital, Rome, Italy, 3Experimental Medicine and Surgery Department, Tor Vergata University, Rome, Italy. Venous stasis and routine hematologic testing. Riggins RB, Thomas KS, Ta HQ, Wen J, Davis RJ, Schuh NR, et al. Effect of tourniquet pressure and intra-individual variability on plasma fibrinogen, platelet P-selectin and monocyte tissue factor. The first step was blood collection and transportation, and the second step was laboratory procedures before the analytical phase. However, being a linear model of relationship, it decomposes the observed effect into a constant (intercept c) and a proportional (slope b) bias (77, 78). The preanalytical phase involves the processes from a physicians request for a laboratory test request to the preparation of a sample for testing [3]. government site. Maybe, since laying in between clinics and laboratory, phlebotomy has long struggled to gain in scientific literature its own identity and the same reputation as laboratory assays. Reducing preanalytical laboratory sample errors through educational and technological interventions. Through the Passing-Bablok regression, it is shown that an alternative procedure compared to the standard for the collection of blood samples caused both systematic (c = -6.46 au; 95% CI: -9.22 to -3.53 au) and proportional (b = 1.16 au; 95% CI: 1.12 to 1.22 au) bias in the analysis of the analyte X. Were all sample tubes immediately and appropriately mixed according to manufacturers specifications? Received 2020 Mar 5; Accepted 2020 Mar 13. It should be also not considered complementary to regression analysis, also because procedures based on least squares estimate do not return independently distributed residuals while the Bland-Altman plot assumes differences to behave otherwise (91). To use the aforementioned tables, it is necessary to input the range of any two series of observation (since the method is invariant and the two must be highly linearly correlated), their dispersion (as coefficient of variation, CV%) and the expected minimum slope change (as ratio). Plebani M. Errors in medicine and errors in laboratory medicine: what is the difference? Could light meal jeopardize laboratory coagulation tests? following errors were not reported at all in the post-analytical phase: transcription error; results not posted; and leaking specimen/broken container. Statistics for the behavioral sciences. In pursuit of harmony, on behalf of European Federation for Clinical Chemistry and Laboratory Medicine (EFLM) Working group for Preanalytical Phase (WG-PRE) Lippi G, Banfi G, Church S, et al. Thereby, in this two-part paper, part I aimed to gather evidences through a review of available literature and summarizing evidence, and part II is concerned with methodological appropriateness and the choice of suitable procedures. Phlebotomy 4 Analytical Errors, Complications, Special Venipuncture The mean was the central tendency measure most frequently used (26/36 papers, 0.75) to summarize data, and in 5/36 cases (0.14) it was used even when the statistic assessment was achieved by means of a non-parametric test (16, 19, 34, 41, 44). For the calculation of the error rates in the one-week observation period, the following cut-offs were used: for fill volume, <90%; for hemolysis, (+) in the visual hemolysis chart. Measurement of iron in serum and EDTA plasma for screening of blood transfusion in sports. The total number of tubes, the number of errors, and the rejections rates are shown in Table Table4.4. Although the majority of the nurses (78%) used safety needles, the safety mechanism was properly activated only in 38% of the interventions. Stat Med 1999;18:2465-78. Plebani M. Quality indicators to detect pre-analytical errors in laboratory testing. 2015). Unable to load your collection due to an error, Unable to load your delegates due to an error. Korevaar DA, van Enst WA, Spijker R, Bossuyt PM, Hooft L. Reporting quality of diagnostic accuracy studies: a systematic review and meta-analysis of investigations on adherence to STARD. 8600 Rockville Pike Bethesda, MD 20894, Web Policies Glasziou P, Altman DG, Bossuyt P, Boutron I, Clarke M, Julious S, et al. reported that the rejection rates for hemolysis, clotted specimen, and insufficient volume were 8%, 24%, and 34%, respectively whereas the fill volume error had the highest rate [14]. In the observation period of the study, the identification of the patient and the labeling of the tubes were found improper according to the EFLM WG-PRE recommendations. Statistical analyses were performed by the Statistical Package for the Social Sciences (SPSS) version 20.0 (SPSS Inc., Chicago, IL) program. Data were analysed with Microsoft Excel (Microsoft Corporation, USA) spreadsheet and StatsDirect 2.7.2 (StatsDirect Ltd., UK) statistical package, representing relative frequencies as proportions according to the author guidelines (7). Were any of the sample tubes clearly under or over filled? We compared patient service times and preanalytical errors pre- and postimplementation of an integrated electronic health record (EHR)-laboratory information system (LIS) and electronic specimen collection module. Although the safety devices were used in 78% of the blood drawing, correct activation of the safety mechanism was performed only by 38%. Are we getting better at the preanalytical phase or just better at The nature of subjects within a cohort should be chosen in order to address a specific diagnostic issue, rather than a generic laboratory concern. 1 Clearly, at least some of these errors will have a major impact on patient care. Plumelle D, Lombard E, Nicolay A, Portugal H. Influence of diet and sample collection time on 77 laboratory tests on healthy adults. Dilauro M, McInnes MD, Korevaar DA, van der Pol CB, Petrcich W, Walther S, et al. 2019 Jul 1;137(7):729-735. doi: 10.1001/jamaophthalmol.2019.0864. Clinical Application of a Safe Blood Sampling Device with an Indwelling Needle. Survey of national guidelines, education and training on phlebotomy in 28 European countries: an original report by the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) working group for the preanalytical phase (WG-PA). Federal government websites often end in .gov or .mil. For the hemolyzed sample, the incorrect fill volume and the clotted sample error types p-values were <0.05, while for the misidentification error, inappropriate tube and erroneous request significance value were >0.05. Second, we observed certain specific drawbacks, some of which strictly related to the conceptual and statistical framework that characterized this kind of studies, and that can be resumed as follows: Particularly, regarding the last three points, the pre-analytical factor, the bias and the agreement were usually treated as if there was no relationship between them, leading to use multiple tests (often redundant) that resulted in a fragmented statistical framework. Makhumula-Nkhoma N, Whittaker V, McSherry R. Pre-analytical errors management in the clinical laboratory: a five-year study. Thus, if a series of observations ranges from cmin to cmax, then: For studies involving a homogeneous population it can be suitably used c = 2, specifying that Passing and Bablok modelled any value 2 c < 4 as c = 2 and 4 c < 8 as c = 4 (73). Cost and Visit Duration of Same-Day Access at an Academic Ophthalmology Department vs Emergency Department. This study emphasizes the importance of the nurse and laboratory staff training during the preanalytical phase and showed that periodic auditing is essential for implementing the existing procedures. The analysis of clotting error rates revealed contradictory findings. Seeking literature, we found 36 suitable investigations issued between 1996 and 2016 (April) dealing with the investigation of pre-analytical factors related to phlebotomy. Therefore, a paper could report a non-significant factor at t-test producing a proportional bias instead, confusing the reader. This study was conducted in Dr. Abdurrahman Yurtaslan Oncology Education and Research Hospital, Ankara, Turkey, which has 600 beds and was equipped to treat surgery and oncology patients. Design, analysis, and interpretation of method-comparison studies. Application of linear regression procedures for method comparison studies in Clinical Chemistry, Part II. Significant Reduction in Preanalytical Errors for Nonphlebotomy Blood Draws After Implementation of a Novel Integrated Specimen Collection Module. Conversely, in 4/36 (0.11) paper it was used a more statistically structured approach based on the total change limit (TCL) or the reference change value (RCV) (13, 14, 19, 41). Appropriate tourniquet time and release were not applied in 84% of the procedures. the comparison of butterfly versus straight needle). Also, the wrong request (e.g. Notably, in 12/36 papers (0.33) no bias estimation was reported, while in 3/36 (0.08) cases a Bland-Altman like plot analysis was used although it was not mentioned as such in methods (37, 38, 43). The most common pre-analytical error was 'improper volume' (41.5%), followed by 'undue clotting' (32.8%). Carrying out a pre-analytical investigation poses some methodological concerns regarding the statistical framework used to assess the investigated factor. Statistical methods in medical research. Fixed and random eects selection in mixed eects models. The author identifies four errors in phlebotomy that are effectively indefensible in a court of law: patient misidentification, improper angle of insertion, improper vein selection, and ineffective training and evaluation of those performing venipunctures. A survey of 116 health research journals. official website and that any information you provide is encrypted For permissions, please e-mail: journals.permissions@oup.com, MeSH The preanalytical QIs were also assessed. (Pre-Post). Harmonization of pre-analytical quality indicators. . Received 2016 Apr 27; Accepted 2016 Nov 25. 9th ed. In this regard, in 2/36 cases (0.06) the authors stated that Students or Wilcoxons test was chosen after the result of a normality test (12, 46). The preanalytical phase involves the processes from a physician's request for a laboratory test request to the preparation of a sample for . Ialongo C, Bernardini S. Phlebotomy, a bridge between laboratory and patient. Lippi G, Salvagno GL, Montagnana M, Poli G, Guidi GC. Utilization of a healthcare failure mode and effects analysis to identify error sources in the preanalytical phase in two tertiary hospital laboratories. During the observation period, 337 blood samples were drawn into 1347 tubes by 73 nurses. kind of tube preservatives or infra-red vein finders). Obviously, there must be correspondence between authors, peer-reviewers and journals to let any new concept reaching acceptance and spreading (110-113). Armitage P, Berry G, Matthews JNS, editors. The observation findings revealed the inadequate education and training procedure of the nurses in the study group and showed that regular education programs must be implemented to them. The preanalytical errors refer to all of the inappropriate performances before the specimens are measured by analyzers, such as improper sample collection, transport delays, illegible handwriting on requisition, and so on. Background: Patient satisfaction in outpatient phlebotomy settings typically depends on wait time and venipuncture experience, and many patients equate their experiences with their overall satisfaction with the hospital. The study has practical implications for our laboratory; corrective strategies to improve the process should be introduced. General recommendations of scientific writing are considered mandatorily applied to these studies (7). inhomogeneity of variance) of data, that may arise due to an underlying heterogeneity of the cohort (65). Careers, Unable to load your collection due to an error. In some studies where N > 30, the sample was partitioned into two or more subgroups on which the analysis was repeated independently, so that the actual sample size varied according to the stratification (28, 32, 33, 38, 43, 45). A concluding remark on statistical methodology regards the recommendation to use the difference plot (better known as Bland-Altman plot) for bias assessment and clinical significance in these studies. Epub 2017 Feb 27. Hemostasis involves activation of the clotting factors and platelets [1]. All of these findings were in compliance with the error types found in this study. Introduction: The study intends to observe the frequency of preanalytical phase errors both inside and outside the clinical laboratory according to certain quality indicators (QIs). In the clinical laboratory testing process, preanalytical, analytical, and postanalytical phases are the three phases of laboratory practice and named as total testing process (TTP) [2-5]. Evaluating agreement between two analytical methods in clinical chemistry. The two major concerns arising from the use of multiple methods are homogeneity of calibration and robustness. It should be remarked that, Passing and Bablok themselves recommended to use always a sample size of 30 at least when applying their model (112). Influence of a light meal on routine haematological tests. Brigden ML, Graydon C, McLeod B, Lesperance M. Prothrombin time determination. Background: observed high rates of patient identification errors at the time of blood sampling, similar to the results of the present study [16]. Since the preanalytical phase step is mainly performed by the staff working outside the laboratory, it is difficult to manage and evaluate quality in this phase [1,12]. For outpatients, six wards were observed. Also after drawing, mixing was not performed properly by the nurses; the mixing cycle was inadequate. Owing to the development of large laboratory networks and of decentralized phlebotomy services and analytical laboratories, standardized and unequivocal procedures and protocols are essential for sample . Effect of drawing a discard tube on PT and APTT results in healthy adults. a regression with more than one predictor) suitable to handle the contribution of individual variability in the analysis of multiple effects (66, 67). Results: The process of blood sample collection from 337 patients taken into 1347 tubes was observed. Influence of the way results are presented on research interpretation and medical decision making: the PRIMER collaboration randomized studies. Lima-Oliveira G, Salvagno GL, Lippi G, Danese E, Gelati M, Montagnana M, et al. The samples are received or rejected by the staff working in the sample reception unit. The experience maturated with the STARD has shown how much all such factors hindered the consolidation of such a new paradigm, despite the wide resonance it had in the scientific literature (106-109). Collection errors can lead to discrepant ABO test results. It can handle both effects that can be experimentally replicated and have the same size for all tested subjects (namely fixed, like two different bore sizes or different stasis duration), and effects that lay outside the experimental control and have a certain variability (namely random, like the homeostatic point of each subject in the study) (66, 68). Lippi G, Lima-Oliveira G, Salvagno GL, Montagnana M, Gelati M, Picheth G, et al. Beyond repeated-measures analysis of variance: advanced statistical methods for the analysis of longitudinal data in anesthesia research. However, the correct device disposal was observed in 36% of them. With respect to the sample size, 14/36 papers (0.39) had N 20, 6/36 (0.17) had N 30, and 16/36 (0.44) had N > 30. Pseudohyperkalemia in patients with chronic lymphocytic leukemia. Dewitte K, Fierens C, Stockl D, Thienpont LM. HHS Vulnerability Disclosure, Help American Society for Clinical Pathology, 2017. For a hypothetical analyte X (expressed in arbitrary units, au), the literature reports CVI = 0.13 (13%), and by the internal quality control it is known that CVA-LOW = 0.21 (21%) around the 25 au level, and CVA-HIGH = 0.14 (14%) around the 85 au. Clinical biochemistry laboratory rejection rates due to various types ofpreanalytical errors. sharing sensitive information, make sure youre on a federal The procedure has the major advantage of computational simplicity and visual immediacy, but in order to emphasize the random component of bias it constrains the modelling of the systematic and proportional components (90). The content published in Cureus is the result of clinical experience and/or research by independent individuals or organizations. Patient satisfaction with respect to phlebotomy was also measured annually using a scoring survey. Actually, they investigate only systematic difference, that is systematic bias at an agreement analysis, and can be considered reliable just when observations cover a narrow range and no significant trend is supposed to arise (80, 81). This observational study aims to evaluate preanalytical phase activity both outside and inside of our clinical laboratory based on selected QIs and to identify the root causes of preanalytical errors. Plebani M, Carraro P. Preanalytical quality improvement:from dream to reality. Clin Biochem. We are grateful to all the laboratory staff and operators. electronic health record; laboratory information system; outpatient phlebotomy; patient satisfaction; positive patient identification; preanalytical errors; wait time. Simundic AM, Cornes M, Grankvist K, Lippi G, Nybo M, Kovalevskaya S, et al. Fibrin was seen in six of the gel tubes. In this regard, we found a lack of association between the appropriateness of summarization and the journal issuing the paper, suggesting that this kind of flaws probably depends on a scarce attention paid by authors to that kind of guidelines. The order of citrated and EDTA tubes was wrong in 5% and 75% of the drawings, respectively. Laboratory errors: How to improve pre- and post-analytical phases Actually, the logic was contrasting the unnecessary multiplication of methods within the statistical framework mostly caused by their customarily use. 8600 Rockville Pike It should be remarked that skewness markedly affects parametric statistics (Students t-test), so that the choice between parametric and non-parametric tests should be made carefully and not only basing on the sample size (59-61). In 22/36 papers (0.61) the study population was represented by healthy volunteers, in 11/36 (0.30) by outpatients, in 1/36 by inpatients (0.03), in 1/36 by blood donors (0.03) and in 1/36 it was not specified (0.03).
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