Rate Of Inadequate Samples Research Articles

Standardization of Sample Handling Methods to Reduce the Rate of Inadequate Sampling

Purpose: The predominant approach for mitigating inadequate sampling rates has primarily involved bolstering the volume of education. This study aimed to curtail inadequate sampling rates through the implementation of continuous quality improvement (CQI) activities, tailoring effective methods to the unique needs of each institution.Methods: We developed a sample handling guidebook and implemented QI activities to address this issue.Results: These measures resulted in a 4.7% decrease in inadequate sampling rates, concurrently improving knowledge of sample handling and overall nurse satisfaction. We addressed the root causes of inadequate sampling before laboratory pre-processing by: 1) focusing on systematic rather than erratic errors through CQI activities, 2) revising the sample handling guide, and 3) delivering face-to-face education based on the specific needs of the nursing department. These changes resulted in an additional 0.6% decrease in the inadequate sampling rate.Conclusion: This study demonstrates that the implementation of CQI activities based on evidence derived from a multifaceted causal analysis significantly reduced the inadequate sampling rate compared to previous studies.

Dynamic Yarn-Tension Detection Using Machine Vision Combined with a Tension Observer.

Machine vision can prevent additional stress on yarn caused by contact measurement, as well as the risk of hairiness and breakage. However, the speed of the machine vision system is limited by image processing, and the tension detection method based on the axially moving model does not take into account the disturbance on yarn caused by motor vibrations. Thus, an embedded system combining machine vision with a tension observer is proposed. The differential equation for the transverse dynamics of the string is established using Hamilton's principle and then solved. A field-programmable gate array (FPGA) is used for image data acquisition, and the image processing algorithm is implemented using a multi-core digital signal processor (DSP). To obtain the yarn vibration frequency in the axially moving model, the brightest centreline grey value of the yarn image is put forward as a reference to determine the feature line. The calculated yarn tension value is then combined with the value obtained using the tension observer based on an adaptive weighted data fusion method in a programmable logic controller (PLC). The results show that the accuracy of the combined tension is improved compared with the original two non-contact methods of tension detection at a faster update rate. The system alleviates the problem of inadequate sampling rate using only machine vision methods and can be applied to future real-time control systems.

Endocervical Sampling in Women With Suspected Cervical Neoplasia: A Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies

ABSTRACT HPV-induced cervical neoplasia progresses through a predictable natural course of disease, starting with mild cervical intraepithelial neoplasia (CIN1) and developing into severe degrees (CIN3) and eventually to invasive cervical cancer. A positive finding on initial screening for cervical neoplasia results in further diagnostics involving sampling with an endocervical brush (EB) or endocervical curettage (ECC). There exists a considerable variation in the choice of test method for obtaining these endocervical or cervical canal samples. This meta-analysis aimed to retrospectively determine the diagnostic test accuracy (DTA) and patient discomfort of the EB and ECC for the detection of cervical neoplasia in women with any indication for colposcopy, biopsies, and endocervical sampling. All diagnostic studies and randomized clinical trials that included women with abnormal cytology results in cervical cancer screening or women with red flag symptoms undergoing colposcopy, biopsy, EB, or ECC were included. The target condition was cervical neoplasia, and the reference standard was the final histological result. A bivariate random-effects model was used to determine summary estimates of sensitivity and specificity with 95% confidence intervals (CIs). A meta-analysis assessing summary relative risk for inadequate samples was also conducted. A total of 7 studies were included in the meta-analysis with a total sample size of 1097 women. Three studies were randomized clinical trials, and 4 were cohort studies, and they took place between 1988 and 2013. A DTA meta-analysis for summary sensitivity and specificity found an overall pooled sensitivity of 81% (95% CI, 48–95) for EB and 70% (95% CI, 42–89) for ECC. The overall pooled specificity was 73% (95% CI, 36–93) for EB and 81% (95% CI, 56–94). The overall relative risk was found to be 2.53 (95% CI, 0.58–11.0; P = 0.215) for ECC compared with EB for inadequate samples. Two studies reported patient discomfort as an outcome, and only a single study reported a significant difference between ECC and EB in favor of ECC (visual analog scale score 2.55 vs 1.99). The results of this meta-analysis comparing the DTA of EB and ECC found no significant difference between EB and ECC in DTA, inadequate sampling rate, or adverse effects. The overall sensitivity was found to be slightly higher for EB than for ECC and the specificity to be slightly higher for ECC than EB, although these results were not statistically significant.

Evaluation of the Novaplex II HPV28 Detection Assay for HPV Typing in Formalin-Fixed, Paraffin-Embedded Tissues

Prophylactic human papillomavirus (HPV) vaccines are recommended for prevention of HPV-associated cancers. Type-specific detection of HPV in formalin-fixed, paraffin-embedded (FFPE) tissues retrieved from diagnostic pathology laboratories is important in monitoring the impact of HPV vaccines. However, few typing assays have been validated for testing FFPE samples. Results of the Novaplex II HPV28 Detection (Novaplex) assay were compared with those from the reference assay (Linear Array with reflex Line Probe Assay) on 708 FFPE samples from cervical lesions. Novaplex showed high type-specific concordance with the reference method for HPV16/18, 9 types targeted by the Gardasil 9 vaccine, 14 high-risk types, and 21 types covered by comparison assays. The rate of inadequate samples was low in both approaches (reference, 3.4%; Novaplex, 1.7%). The proportion of discrepant types was less than 3.5% and positive concordance was greater than 75.0%. Furthermore, the type-specific positive agreement (92.0% to 98.0%), negative agreement (96.0% to 99.0%), and accuracy (97.0% to 99.0%) was high. Cohen's κ ranged from 0.86 to 0.89, indicating excellent agreement between Novaplex and reference assays. The results show that Novaplex is a suitable method for detection of HPV in FFPE tissues.

Implementation of Big Data to Develop Origin-Destination Matrix Estimation Model

Big data is a huge collection of electronic data which is currently popular to be developed in various scientific fields, including the transportation sector. Several data categories that can be used for transportation infrastructure planning are real-time location/position and timestamp of road users. This technological sophistication addresses a very crucial transportation planning problem that has been faced for many years, that is the inaccurate and unrepresentative prediction of the Origin-Destination Matrix. Up to this point, the Origin-Destination Matrix has been obtained using conventional and unconventional methods. Data was collected through manual traffic counts survey and direct interview in the study area. This results in unreliable data and inadequate sampling rates, which are only able to cover 20% of the population. In addition, the application of these techniques is expensive, time-consuming, and require a lot of human resources. Therefore, this study tries to develop a model capable of predicting the origin and destination of mobility, which in this case is represented by the sub-district boundary as a zone. As a result, an Origin-Destination Matrix can be obtained with a high degree of accuracy. The case study used is Bandung city. In the future, this research is expected to become a milestone in elaborating a validated Origin-Destination Matrix estimation model that can be used in various areas.

Pile-Up Correction in Spectroscopic Signals Using Regularized Sparse Reconstruction

Pile-up is a common problem in high-count-rate gamma spectroscopy. Many techniques have been introduced to overcome this problem. Sparse reconstruction is a recent signal processing method that could be used to solve this problem. In this article, we propose a modified sparse reconstruction method to overcome pulse pile-up, especially with ultrahigh count rates. The method uses two regularization terms to compensate for the error caused by an inadequate sampling rate that is called the “verbosity” problem. It significantly improves the pile-up correction process. A scintillation detector pulse train is simulated in different rates by a Monte Carlo approach. Then, the proposed method is validated, and good results are achieved in ultrahigh count rates.

Inadequate Sampling Rates Can Undermine the Reliability of Ecological Interaction Estimation

Cycles in population dynamics are abundant in nature and are understood as emerging from the interaction among coupled species. When sampling is conducted at a slow rate compared to the population cycle period (aliasing effect), one is prone to misinterpretations. However, aliasing has been poorly addressed in coupled population dynamics. To illustrate the aliasing effect, the Lotka–Volterra model oscillatory regime is numerically sampled, creating prey–predator cycles. We show that inadequate sampling rates may produce inversions in the cause-effect relationship among other artifacts. More generally, slow acquisition rates may distort data interpretation and produce deceptive patterns and eventually leading to misinterpretations, as predators becoming preys. Experiments in coupled population dynamics should be designed that address the eventual aliasing effect.

User perception of endocervical sampling: A randomized comparison of endocervical evaluation with the curette vs cytobrush.

ObjectivesTo evaluate whether the endocervical brush (ECB) is better accepted by patients and health care providers for endocervical evaluation when compared to the endocervical curette (ECC), without a decrease in the quality of sampling.MethodsTwo hundred patients with cervical dysplasia were randomized at the colposcopy clinic of the University Hospital of Geneva into two groups according to technique. Patients and physicians’ preference regarding the technique as well as the quality of samples were assessed. ECB samples were analyzed using both cytological (cell block) and histologic analysis, while ECC samples were analyzed using standard histologic analysis.ResultsOf the 200 patients, 89 were randomized to ECC, 101 to ECB and 10 were excluded due to incomplete information or cervical stenosis. Physicians preferred ECB against ECC, classifying it more frequently as an easy technique (94.1% vs.61.4%, p<0.001). Physicians more frequently evaluated the ECB as little or not uncomfortable for patients (28.7% vs.10.2%, p<0.001), though patients themselves didn’t express a preference for either technique. From a quality standpoint, the brush allowed for a better quality of samples, with a lower rate of inadequate samples (2.0% vs 14.3%, p = 0.002) and greater amount of material.ConclusionEndocervical sampling using ECB seems to be easier to perform and provides better quality samples. ECB can therefore be an acceptable alternative to ECC in standard practice.Trial registrationClinicalTrials.gov NCT01435590

A Comparison of the Diagnostic Efficiency of Guided Fine Needle Aspiration Cytology Versus Conventional Fine Needle Aspiration Cytology of the Thyroid.

Fine needle aspiration cytology (FNAC) is possibly the most useful investigation for the thyroid. However, conventional FNAC (C-FNAC) is limited by a high rate of inadequate samples. Ultrasound guided FNAC (US-FNAC) has been proposed as an alternative. This study aims to estimate the measures of diagnostic accuracy of FNAC as well as to compare US-FNAC against C-FNAC. Patients who underwent FNAC at our for a period of 5years were selected. This comprised of 237 C-FNAC cases and 173 US-FNAC cases. Out of these 410 cases, 129 cases had cyto-histological correlation. The proportion of inadequate samples, malignant cases as well as indeterminate cases were compared between US-FNAC and C-FNAC. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), likelihood ratios for positive and negative results and odds ratio were estimated for overall FNAC as well as US-FNAC and C-FNAC patients. US-FNAC has a significantly lower proportion of inadequate samples (0.58 vs. 15.19%), as well as a lower proportion of indeterminate samples (1.7 vs. 7.6%) and a higher proportion of malignant cases (6.4 vs. 2.1%). When the inadequate samples were excluded, the results for tests of diagnostic effectiveness for overall FNAC, US-FNAC and C-FNAC respectively ranged between 66.67 and 80% for sensitivity, between 86.05 and 100% for specificity, between 45.45 and 100% for PPV and between 97.37 and 98.7% for NPV. FNAC is a useful test for differentiating malignant from benign lesions. When inadequate samples are excluded, both US-FNAC and C-FNAC are accurate diagnostic tests. However, US-FNAC is a more useful test since it results in a lower number of inadequate samples. Also, US-FNAC results in a greater yield of malignancy and a lower percentage of indeterminates, possibly due to additional information received from ultrasound examination.

Accuracy, Sensitivity and Specificity of Fine Needle Aspiration Biopsy for Salivary Gland Tumors: A Retrospective Study from 2006 to 2011

Objective:This article concerns evaluation of the sensitivity, specificity and accuracy of FNAB for pre-surgical diagnosis of benign and malignant lesions of major and minor salivary glands of patients treated in the Department of Head and Neck Surgery of Erasto Gartner Hospital.Methods:This retrospective study analyzed medical records from January 2006 to December 2011 from patients with salivary gland lesions who underwent preoperative FNAB and, after surgical excision of the lesion, histopathological examination.Results:The study had a cohort of 130 cases, but 34 cases (26.2%) were considered unsatisfactory regarding cytology analyses. Based on the data, sensitivity was 66.7% (6/9), specificity was 81.6% (71/87), accuracy was 80.2% (77/96), the positive predictive value was 66,7% (6/9) and the negative predictive value was 81.6% (71/87).Conclusion:Despite the high rate of inadequate samples obtained in the FNAB in this study the technique offers high specificity, accuracy and acceptable sensitivity.

Routine non-thyroid head and neck cytology in a large UK centre: clinical utility and pitfalls.

This study aimed to examine the performance of head and neck cytology at Nottingham University Hospitals between 2009 and 2010. Cases were extracted from the Winpath pathology reporting system and correlations were investigated between results and the histological and clinical outcomes. Specimen adequacy and the sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy of the cytology tests were calculated. In all, 19.7 per cent of aspirates were judged to be inadequate. The absolute and relative sensitivities of head and neck cytology were 87.0 per cent and 89.0 per cent, respectively, and the absolute and relative specificities were 99.0 per cent and 97.0 per cent, respectively. The positive predictive values were 99.0 per cent and 96.0 per cent and the negative predictive values were 92.0 per cent and 92.0 per cent for a diagnostic accuracy of 94.5 per cent and 93.0 per cent. The performance was consistent with previous reports and superior to that of a recent UK series. The high rate of inadequate samples is, however, a concern. Head and neck cytology is a robust technique at our institution, although there are certain problem areas. There is room for improvement in the technical quality of fine needle aspiration.

Surgeon-performed ultrasound-guided fine-needle aspiration cytology of head and neck mass lesions: sampling adequacy and diagnostic accuracy.

Studies of surgeon-performed ultrasound-guided fine-needle aspiration cytology (US-FNAC) have been limited largely to thyroid nodules. This study evaluated the sampling adequacy and diagnostic accuracy of surgeon-performed US-FNAC for a large range of head and neck mass lesions, including lesions of the thyroid, salivary glands, and lymph nodes. The study included 617 cases of US-FNAC performed by a single surgeon between 2009 and 2013. Their medical histories and ultrasound (US) findings were retrospectively reviewed. Sample adequacy was analyzed according to the surgeon's experience, anatomic tumor location, and US tumor characteristics. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of FNAC were calculated after correlation with the surgical histopathologic results. The overall adequacy rate for surgeon-performed US-FNAC was 91.9 % (567/617). Inadequate specimens were obtained from 9.7 % (29/282) of the thyroid glands, 6.1 % of the salivary glands (6/98), and 6.3 % (15/237) of the lymph nodes. The effect of the surgeon's experience plateaued (inadequate sampling rate, 6-8 %) after 100 US-FNAC procedures. Inadequate sampling was associated with tumor characteristics such as cystic change and rim calcification. Overall, US-FNAC showed a sensitivity of 88.2 %, a specificity of 98.2 %, a PPV of 98.5 %, an NPV of 85.7 %, and a diagnostic accuracy of 91.6 %. With proper training and experience managing at least 100 US-FNAC cases, surgeons can ensure a low inadequate sampling rate and good diagnostic accuracy for a range of head and neck mass lesions.

A systematic review and meta-analysis of palpation versus ultrasound-guided fine needle aspiration of thyroid nodules

Background: Thyroid nodules are a common clinical finding. Fine-needle aspiration (FNA) is the most widely accepted diagnostic tool used to differentiate malignant and benign thyroid nodules. FNA can be carried out by manual palpation of the nodule or with ultrasound guidance. Existing clinical practice guidelines give mixed recommendations regarding the use of ultrasound guidance for thyroid FNA. Given the inconsistencies in the guidelines, we performed a systematic review and meta-analysis to compare the diagnostic accuracy of palpationguided fine needle aspiration (PG-FNA) versus ultrasound-guided fine needle aspiration (USG-FNA). Methods: Studies comparing PG-FNA and USG-FNA were identified through a search of PubMed, the Cochrane Library, and Embase (1990- December 2011). Titles and abstracts were reviewed and studies were selected for a full text review. Meta-analysis of included studies was performed to estimate the average sensitivity, specificity, and rate of inadequate samples for each technique. Results: We screened 1934 citations and selected seven studies meeting our predefined inclusion criteria. The pooled sensitivity of USG-FNA was found to be higher than PG-FNA [0.91 (CI=0.82, 1.0) and 0.79 (CI=0.69, 0.85), respectively]. The pooled specificity of USG-FNA was also found to be slightly higher than PG-FNA [0.77 (CI=0.69, 0.85) and 0.73 (CI=0.64, 0.81), respectively]. The mean rate of inadequate samples was higher for PG-FNA at 14.7% versus 8.4% for US-FNA. Conclusions: Our findings show that USG-FNA has a higher diagnostic accuracy than PG-FNA and a lower rate of inadequate samples. Overall, these findings suggest an advantage to the use of USG-FNA over PG-FNA.

Http://www.omicsonline.org/open-access/accuracy-of-combined-tru-cut-and-fnac-in-preoperative-sampling-of-ovarian-tumors-2161-0681.1000168.php?aid=26242

Background: Preoperative histologic confirmation of malignant ovarian tumors before chemotherapy is mandatory. There are few reports about combined use of tru cut and FNAC as methods of preoperative sampling of ovarian tumors. Patients and methods: This is a prospective study conducted on 50 female patients presented with advanced ovarian tumors, during the period between 1/6/2011 and 31/10/2013. Trans-abdominal ultrasound guided tru cut biopsy and FNAC were performed for the patients at the same setting. The results were compared with the postoperative histopathology reports which considered as the gold standard. Results: Of the 50 tru cut procedures; 46 cases (92%) revealed diagnostic tissue and 4 specimens were rendered non representative. The diagnostic accuracy of tru cut biopsy is 95.7% with sensitivity is 94.7% and specificity 100%. The diagnostic accuracy of FNAC is 95% with sensitivity is 94.3% and specificity 100%. The Positive predictive value is 100% for both techniques. The negative predictive value for tru cut and FNAC is 80% and 71.4% respectively. When tru cut was combined with FNAC the rate of inadequate samples have fallen to 0. The diagnostic accuracy of combined tru cut and FNAC was 95.5% with sensitivity is 94.9% and specificity 100%. The positive predictive value was 100% and the negative predictive value was 71.4%. Conclusion: Both tru cut and FNAC are complementary to each other in achieving adequate samples for preoperative histologic diagnosis of ovarian tumors. Even if the diagnostic accuracy wasn't changed markedly, obtaining adequate samples can justify the beneficial combination of both techniques that will reduce the hazards and costs when a single technique has to be repeated to obtain sufficient tissues for diagnosis.

Endoscopic ultrasound guided transbronchial fine needle aspiration: a French Department of Pathology's 4-year experience

BackgroundEndobronchial ultrasound (EBUS) guided transbronchial needle aspiration (TBNA) is an accurate outpatient procedure used to explore mediastinal lymph nodes for lung cancer staging and unexplained mediastinal masses.Aims and methodsA retrospective...

Thyroid fine needle aspiration cytology processed by ThinPrep: an additional slide decreased the number of inadequate results

Fine needle aspiration cytology is the most accurate tool for diagnosing thyroid nodules. Its accuracy is related to the rate of inadequate samples, which can be minimized with the adoption of on-site assessment of the adequacy of the material. The introduction of liquid-based cytology (LBC) in the thyroid does not allow checking on the adequacy of the cellularity. The possibility of making a second LBC slide for decreasing the number of non-diagnostic cases is studied. Out of 553 cases diagnosed in a single institution from January to March 2005, 166 consecutive cases with an LBC slide reviewed by the same pathologist were evaluated. The cases were classified in a five-tiered category system (Thy1 to 5 according to the British Thyroid Association guidelines) and all but two (with cystic degeneration) were processed by LBC and stained with Papanicolaou stain. The above-mentioned categories are defined as follows: Thy1 inadequate or haemorrhagic, Thy2 non-neoplastic lesion; Thy3 follicular lesion/suspected follicular neoplasm; Thy4 suspicious for malignancy; Thy5 diagnostic of malignancy. For each case the cytological diagnosis was made on the LBC slide and the adequacy of the cellularity for a conclusive diagnosis was assessed. Of the 166 cases, 39 were non-diagnostic (Thy1-inadequate), ten presented features of cystic degeneration (Thy1-haemorrhagic), 90 were benign (Thy2), 22 were diagnosed as a follicular lesion (Thy3), one as suspicious of malignancy (Thy4) and four as papillary carcinoma (Thy5). Thirty-nine cases had a second LBC for achieving a definitive diagnosis with eventual re-classification. Of these cases, 23 (61.5%) led to a conclusive diagnosis (18 Thy2, five Thy3) with a 18.5% decrease of the inadequacy rate. The making of an additional LBC slide helps in achieving a diagnosis in cases classified as non-diagnostic on the first standard slide (52.1% recovery rate). This procedure is particularly helpful for meeting the adequacy criteria in benign and indeterminate lesions and could also be used for refining the diagnosis of suspicious for a malignant thyroid neoplasm.

Ultrasonography-Guided Fine-Needle Aspiration Biopsy of Predominantly Cystic Thyroid Nodules

Purpose: The aim of this study is to present our biopsy technique and to determine the efficacy of the ultrasound-guided fine-needle aspiration biopsy (US-FNAB) for predominantly cystic thyroid nodules (PCTNs). Materials and Methods: This study included patients that underwent US-FNABs on PCTNs, and were sampled for the solid component following the aspiration of a cystic component through one needle puncture between January to December of 2008. We retrospectively reviewed the cytopathology results as well as any complication associated with the procedure. Results: Of the 76 PCTNs (range of maximal diameter: 0.4 cm-6.1 cm, mean: 2.39 cm) observed in the 75 patients (females: males - 63: 12, age range: 19-72, mean: 45.3 years old), the incidence rate of adequate and inadequate samples was 90.8% (69/76) and 9.2% (7/76) in the first US-FNAB, respectively. Further, 23 PCTNs were surgically removed in 22 patients, of which 15 PCTNs were benign and 8 were confirmed malignant nodules. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for USFNAB of PCTNs were 95.2%, 100%, 100%, 76.9%, and 95.8%, respectively. Conclusion: The data suggest that our technique for US-FNAB of PCTNs was effective and accurate.

Accuracy, sensitivity and specificity of fine needle aspiration biopsy in salivary gland tumours: A retrospective study

The aim of this study was to evaluate the diagnostic accuracy, sensitivity and specificity of fine needle aspiration biopsies (FNAB) of salivary gland tumours performed at the Erasto Gaertner Hospital over the course of a four year period. A retrospective study was carried out between 2001-2005 to review the cases of patients with salivary gland tumours who had undergone pre-operative FNAB and had been diagnosed during post-operative histopathology examination. A total of 106 cases of salivary gland tumours were considered for this study, but 27 cases (25.5%) of the samples were considered unsatisfactory for analysis. The sensitivity, specificity and accuracy were calculated considering only the 79 benign and malignant cases in which FNAB provided sufficient samples for analysis. Based on these data, the value of sensitivity was 68.2% (15/22), specificity was 87.7% (50/57), accuracy was 82.3% (65/79), positive predictive value was 68.2% (15/22) and negative predictive value was 87.7% (50/57). Despite the high rate of inadequate samples obtained in the FNAB in this study, the technique offers high specificity, accuracy and acceptable sensitivity.

Comparison of Preoperative Fine-needle Aspiration Cytology Diagnosis and Histopathological Diagnosis of Salivary Gland Tumors

We investigated 115 patients with salivary gland epithelial tumors who had undergone preoperative fine needle aspiration cytology (FNAC) of salivary glands and had been diagnosed by postoperative histopathological examination. We compared the findings of preoperative FNAC with their histopathological types in salivary gland tumors, and discuss the results and problems. The diagnostic accuracy, sensitivity, and specificity of preoperative FNAC of salivary glands were 98.2%, 88.2%, and 100%, respectively. The percentage of inadequate specimens was 6.1%. The rates of agreement in the diagnosis of pleomorphic adenoma, Warthin tumor, and basal cell adenoma were 96%, 92.9%, and 55.5%, respectively. The rate of agreement of histopathological types in the malignant tumors was 30%. We realized again not only that the diagnostic accuracy of preoperative FNAC for salivary gland tumors was high, but also that it was a safe, easy-to-perform, clinically very useful diagnostic procedure. However, this study exposed several problems which are the inadequate sampling rate and the difficulty in diagnosing malignant tumors. We have been making efforts to take appropriate specimens by writing comments on the cytological report indicating a re-examination, or by the presence of the clinical laboratory technician at the FNAC procedure. We consider it necessary to adequately re-aspirate the solid portion after cyst fluid aspiration, or to re-perform FNAC at a later date, and to improve the diagnostic accuracy by further experience with more patients.

Combined static and dynamic analysis for determining the quality of time-series expression profiles

Expression profiling of time-series experiments is widely used to study biological systems. However, determining the quality of the resulting profiles remains a fundamental problem. Because of inadequate sampling rates, the effect of arrest-and-release methods and loss of synchronization, the measurements obtained from a series of time points may not accurately represent the underlying expression profiles. To solve this, we propose an approach that combines time-series and static (average) expression data analysis--for each gene, we determine whether its temporal expression profile can be reconciled with its static expression levels. We show that by combining synchronized and unsynchronized human cell cycle data, we can identify many cycling genes that are missed when using only time-series data. The algorithm also correctly distinguishes cycling genes from genes that specifically react to an environmental stimulus even if they share similar temporal expression profiles. Experimental validation of these results shows the utility of this analytical approach for determining the accuracy of gene expression patterns.