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Reliability of the DSM-III-R childhood anxiety disorders using structured interview: interrater and parent-child agreement.

OBJECTIVE: The aim of the study was to examine the interrater and parent-child agreement for the major child anxiety disorders. METHOD: One hundred sixty-one children and their parents underwent a semistructured interview (Anxiety Disorders Interview Schedule for Children). To increase external validity, clinicians did not receive specific, extensive training in diagnosing anxiety disorders apart from their standard qualifications. The design of the study allowed for calculation of agreement between raters based on information obtained from the parents alone, from the child alone, or through combined information from both the parents and child, and for calculation of agreement between information obtained from the parents and information obtained from the child. RESULTS: Levels of interrater agreement either as principal or additional diagnoses were moderate to strong for all of the major childhood anxiety disorders (kappa values .59 to .82). In contrast, parent-child agreement was poor for most diagnostic categories (kappa values .11 to .44). CONCLUSIONS: The data indicate that, despite the fact that parents and their children do not demonstrate strong agreement, the DSM-III-R childhood anxiety disorders can be reliably diagnosed by pairs of general clinicians using structured interviews.

Adolescent↗

Psychiatric comorbidity associated with DSM-IV ADHD in a nonreferred sample of twins.

OBJECTIVE: To test the external validity of the dimensions and subtypes of DSM-IV attention-deficit/hyperactivity disorder (ADHD) by assessing the prevalence of psychiatric comorbidity. METHOD: Eight- to 18-year-old twins with ADHD (n = 105) and without ADHD (n = 95) were recruited through local school districts. Comorbid disorders were assessed by structured diagnostic interviews with the parent and child and by a behavioral rating scale completed by the child's classroom teacher. RESULTS: Symptoms of inattention were associated with lower intelligence and higher levels of depression, whereas symptoms of hyperactivity-impulsivity were associated more strongly with symptoms of oppositional defiant disorder (ODD) and conduct disorder (CD). All DSM-IV subtypes were associated with higher rates of ODD and CD in comparison with controls, and the combined type was associated with more disruptive behavior disorder symptoms than the other 2 subtypes. The combined type and predominantly inattentive type were associated with more symptoms of depression than controls or the predominantly hyperactive-impulsive type. CONCLUSIONS: These results provide support for the discriminant validity of the dimensions and subtypes of DSM-IV ADHD and suggest that clinicians should carefully screen for comorbid disorders as part of a comprehensive assessment of ADHD.

Adolescent↗

Assessing the efficacy of treatments for panic disorder and agoraphobia. II. The Panic and Agoraphobia Scale.

Despite the plethora of rating scales for anxiety disorders and agoraphobia, a qualified scale for assessing the severity of panic disorder and agoraphobia (PDA) is still lacking. The new Panic and Agoraphobia Scale (P&A) is presented in this paper. It was developed to assess the degree of severity of these disorders after a diagnosis has been made according to the criteria of the DSM-III-R/IV or the ICD-10. The P&A was specially developed for use in clinical drug trials. Factors which impair the quality of life in panic disorder and agoraphobia patients (panic attacks, phobic avoidance, anticipatory anxiety, impairment in social relationships and work, assumption of somatic disease) were considered in the development of this scale so that the efficacy of a certain drug therapy on each of these factors can be assessed separately. Both an observer rating and a self-rating with matching items are available. The observer rating only takes about 10 minutes to complete. Translation into many European languages is planned so that it can be used in multicentre trials. Satisfactory results of item analysis, inter-rater reliability, objectivity, external validity and factor structure are presented. The P&A should be a useful tool for assessing the severity of PDA and may solve some of the methodological problems that have arisen in former PDA studies.

Adult↗

Empirically derived MMPI profiles. Coronary bypass surgery.

A cluster analysis of eight clinical scales of the MMPI-168 was performed on data from 129 subjects awaiting coronary bypass surgery. Four abnormal profiles were derived and these profiles were consistent with clinical expectancy. The five empirically derived profiles were labeled as a) normal--that is, no elevated scales; b) marginal distress--elevated Hs; c) conversion V--elevated Hs and Hy; d) neurotic--elevated Hs, D, Hy, and Pt; and e) generalized distress--elevated D, Hy, Pd, Pa, Pt, and Sc. Subsequent postsurgical follow-ups were done at 3-, 12-, and 24-month intervals. These data suggest that the profiles retained their characteristic shape and were still statistically different from each other, but the overall elevation decreased significantly after successful surgical intervention. To externally validate these profiles, the five derived groups were compared in terms of Beck Depression scores and the State/Trait Anxiety Inventory. These results were consistent with the MMPI. These data are discussed in terms of developing models for assessing the interaction of personality and specific stressors.

Adult↗

Comparison of methods for estimating fecal carbohydrate excretion in premature infants.

Our previous studies have suggested that there is minimal fecal excretion of carbohydrate-derived energy in premature infants fed lactose or glucose-polymer as the source of carbohydrate. In these studies, carbohydrate energy excretion was equated with the non-nitrogenous, nonfat energy. Although these studies provided consistent results, this methodological approach cannot distinguish actual excretion of dietary carbohydrate from carbohydrate in the form of large molecular compounds derived from infant or bacterial cells (which in fact comprise approximately 90% of the measured value). Therefore, in this study we compared the absorption of carbohydrate energy to the fractional absorption of 13C derived from [D-1-13C]-lactose in 10 premature infants 30-32 weeks gestational age fed either a commercial premature infant formula containing a mixture of carbohydrates (50% lactose: 50% glucose polymer) or the same formula in which lactose was the sole carbohydrate. The two methods provided comparable estimates of carbohydrate absorption (96 and 94%, respectively), although there were significant discrepancies in two infants. These studies provide evidence of external validity for the two methods.

Carbohydrate Metabolism↗

Bullet trajectory predicts the need for damage control: an artificial neural network model.

BACKGROUND: Effective use of damage control in trauma hinges on an early decision to use it. Bullet trajectory has never been studied as a marker for damage control. We hypothesize that this decision can be predicted by an artificial neural network (ANN) model based on the bullet trajectory and the patient's blood pressure. METHODS: A multilayer perceptron ANN predictive model was developed from a data set of 312 patients with single abdominal gunshot injuries. Input variables were the bullet path, trajectory patterns, and admission systolic pressure. The output variable was either a damage control laparotomy or intraoperative death. The best performing ANN was implemented on prospectively collected data from 34 patients. RESULTS: The model achieved a correct classification rate of 0.96 and area under the receiver operating characteristic curve of 0.94. External validation showed the model to have a sensitivity of 88% and specificity of 96%. Model implementation on the prospectively collected data had a correct classification rate of 0.91. Sensitivity analysis showed that systolic pressure, bullet path across the midline, and trajectory involving the right upper quadrant were the three most important input variables. CONCLUSION: Bullet trajectory is an important, hitherto unrecognized, factor that should be incorporated into the decision to use damage control.

Abdominal Injuries↗

Multisite randomized controlled trials in health services research: scientific challenges and operational issues.

Although well-designed randomized controlled trials (RCT) provide the strongest evidence regarding causation, only relatively recently have they been used by health services researchers to study the organization, delivery, quality, and outcomes of care. More recent yet is the extension of multisite RCTs to health services research. Such studies offer numerous methodological advantages over single-site trials: (1) enhanced external validity; (2) greater statistical power when studying conditions with a low incidence or prevalence, small event rate in the outcome (eg, mortality), and/or large variance in the outcome (eg, health care costs); and (3) rapid recruitment to provide health care organizations and policy makers with timely results. This paper begins by outlining the advantages of multisite RCTs over single-site trials. It then discusses both scientific challenges (ie, standardizing eligibility criteria, defining and standardizing the intervention, defining usual care, standardizing the data collection protocol, blinded outcome assessment, data management and analysis, measuring health care costs) and operational issues (ie, site selection, randomization procedures, patient accrual, maintaining enthusiasm, oversight) posed by multisite RCTs in health services research. Recommendations are offered to health services researchers interested in conducting such studies.

Cost Control↗

Challenges to intervention implementation: lessons learned in the Bathing Persons with Alzheimer's Disease at Home study.

BACKGROUND: The pressing need for interventions to improve outcomes for vulnerable caregivers of individuals with Alzheimer's disease (AD) is hindered by inadequate knowledge of variables affecting intervention delivery, receipt, and enactment. OBJECTIVE: To analyze intervention implementation issues encountered within the Bathing Persons with Alzheimer's Disease at Home (BATH) study. METHODS: The BATH study, a home-based, randomized, controlled trial of interventions to improve behavioral symptoms and caregiver self-efficacy, consisted of 130 intervention visits to 42 care recipients-caregiver dyads. Data include direct observation, nurse interventionist field notes, case analyses, and caregiver journals, reflecting various perspectives. Content analysis was used to identify key treatment process themes. RESULTS: Issues that affected the delivery, receipt, and enactment of interventions reflect the intersection of in vivo caregiving and research design. DISCUSSION: The primary lessons learned were: (a) early identification of caring dyads prior to crisis must be improved; (b) in vivo observation is essential to individualized interventions targeting behavioral etiologies and developing caregiver skills; (c) intervention delivery depends on the nurse interventionist's skills and a flexible, trusting researcher-dyad relationship; (d) complex caregiver situations affect treatment receipt and enactment; and (e) intervention enactment requires coaching, practice, and support over time. These findings help to explain issues impacting intervention implementation to a vulnerable population. Recommendations for intervention research design to maximize internal and external validity in real-life care contexts can inform future outcome studies, aid in the search for improved care, and lead to supportive public policy for families living with AD.

Adult↗

Pediatric ambulance utilization in a large American city: a systems analysis approach.

BACKGROUND: Research on utilization of ambulances by pediatric patients lacks an objective, reproducible tool for the evaluation of patterns of ambulance use by both the providers and the users of this resource. OBJECTIVES: 1) To develop an objective, diagnosis-based measure of appropriateness of ambulance utilization. 2) To use the measure to evaluate whether Municipal Ambulance Service dispatchers assign ambulances appropriately, and whether parents/caretakers request ambulances appropriately. STUDY DESIGN: 1) Development of the pediatric ambulance need evaluation (PANE) tool: The consensus of an expert panel was used to assign patients arriving by ambulance to three levels of prehospital transport need based upon their ultimate hospital discharge diagnoses, and were as follows: required advanced life support ambulance (ALS); required basic life support ambulance (BLS); required a less acute mode of transport (LAT). 2) Assessment of appropriateness of ambulance assignments by EMS call-receiving operators (CRO) and of ambulance requests by parents/caretakers: Comparison of actual type of ambulance assigned and of need for ambulance, using the PANE tool and hospital admission rates as gold standards. DATA COLLECTION: Level of prehospital transport provided (ALS vs BLS), ultimate ED diagnosis, and ED disposition (admission vs discharge) was collected for each patient from information abstracted from the prehospital and ED records. SETTING: Bellevue Hospital Center and Harlem Hospital Center, two level I trauma centers in New York City, both with Pediatric Emergency Departments staffed 24 hours a day by attending physicians and residents. PATIENT SELECTION: Consecutive sample of 2633 patients, birth to 18 years of age, who arrived to either hospital by ambulance as primary transports from the field over a one-year period. RESULTS: 1) Development of PANE tool: At Bellevue Hospital, 7% of ED visits arrived by ambulance; at Harlem Hospital, 5% arrived by ambulance. Using these ambulance arrivals, 215 diagnoses were identified for inclusion in the PANE tool. An expert panel categorized each diagnosis as requiring ALS, BLS, or LAT, with a high level of interobserver agreement (weighted kappa = 0.793). As a measure of external validity of the PANE, admission rates were highest in the ALS group, next highest in the BLS group, and lowest in the LAT group (chi2 for trend, P < 0.05). 2) Assessment of ambulance assignments and requests: According to the PANE tool, the sensitivity of dispatcher assignment of ALS ambulances was 72 %. Therefore, 28 % of patients who required an ALS ambulance received BLS care. 50% of patients assigned to an ALS ambulance did not require that level of care, and 1/3 of these were categorized by the PANE as not requiring an ambulance at all. CONCLUSIONS: The PANE tool compared favorably to admission rates as a measure of the severity of illness of patients arriving by ambulance. Applying the PANE tool, we conclude that the majority of requests for ambulances are appropriate, and that the majority of the time dispatchers were able to dispatch the appropriate level of care. However, there is room for significant improvement in utilization of ambulances, and tools like the PANE will be useful in achieving this goal.

Adolescent↗

A new unsupported upper limb exercise test for patients with chronic obstructive pulmonary disease.

UNLABELLED: PURPOSE This study aimed to develop a new unsupported upper limb exercise test (UULEX) for patients with chronic obstructive pulmonary disease (COPD). METHODS: The reproducibility of the UULEX was assessed in nine patients with COPD who performed the test on three occasions. A comparison of the UULEX and a supported incremental upper limb exercise test (SULEX) using an arm ergometer also was performed with 18 patients who had COPD. RESULTS: There were no significant differences in the maximum values for each cardiorespiratory variable and sensation of dyspnea between the three repetitions of the UULEX, and all the variables showed high reproducibility. During the supported test, maximum values for the cardiorespiratory variables were significantly higher, but the ratio of minute ventilation to carbon dioxide output was lower than during the unsupported exercise test. There were significant correlations for cardiorespiratory responses, arm muscle fatigue, and sensation of dyspnea between the two tests. CONCLUSIONS: The findings suggest that the new UULEX test is a reproducible and acceptable exercise test for patients with COPD that can be used as a simple method to evaluate upper limb function in these patients. Further studies are required to determine the external validity of the test and its sensitivity to interventions such as pulmonary rehabilitation.

Aged↗

Performance problems of patients with chronic low-back pain and the measurement of patient-centered outcome.

STUDY DESIGN: In a prospective interventional study, problems with performance were evaluated in 101 consecutive patients with chronic low-back pain for more than 12 months, before and after participation in an outpatient-based multidisciplinary pain management program in Mansfield, United Kingdom. OBJECTIVES: To describe problems identified as most important by patients with chronic low-back pain and to evaluate the Canadian Occupational Performance Measure (COPM) as a tool for measuring problem-specific outcomes. SUMMARY OF BACKGROUND DATA: Patients with chronic low-back pain report difficulties with a variety of activities. The COPM permits the identification and measurement of problems of particular concern to the patient. MATERIALS AND METHODS: COPM, likert-modified Roland and Morris Disability Questionnaire, Pain Self-Efficacy Questionnaire, and 5-minute walk test were administered at baseline, immediately after, and 9 months after intervention. Differences and statistical interactions were determined by nonparametric tests. RESULTS: Participants identified 60 different types of problem activity, 45 of which were identified by nine or fewer participants. Decreased walking tolerance was the most frequently identified problem (56% of participants). Improvements were observed in all outcomes following intervention. Approximately one third of participants reported improvements two or more COPM units in overall performance and satisfaction with their performance at 9 months. Higher reported performance and satisfaction were associated with greater self-efficacy. Increased reported walking performance was associated with increased observed 5-minute walk distance (R = 0.35, P = 0.02). CONCLUSIONS: Patients with chronic low-back pain report problems with diverse activities. The COPM provides a patient-centered outcome measure that displays good external validity and responsiveness to change when addressing the individual's goals.

Adult↗

The Treatment for Adolescents With Depression Study (TADS): demographic and clinical characteristics.

OBJECTIVE: The Treatment for Adolescents With Depression Study is a multicenter, randomized clinical trial sponsored by the NIMH. This study is designed to evaluate the short- and long-term effectiveness of four treatments for adolescents with major depressive disorder: fluoxetine, cognitive-behavioral therapy, their combination, and, acutely, pill placebo. This report describes the demographic and clinical characteristics of the sample and addresses external validity. METHOD: Participants are 439 adolescents, aged 12-17 years inclusively, with a primary DSM-IV diagnosis of current major depressive disorder. Baseline data are summarized and compared with those from national samples and previous trials. RESULTS: The sample composition is 54.4% girls, 73.8% white, 12.5% African American, and 8.9% Hispanic. The mean Child Depression Rating Scale-Revised total score is 60.1 (SD = 10.4, range 45-98) with 86.0% experiencing their first major depressive episode. The most common concurrent diagnoses are generalized anxiety disorder (15.3%), attention-deficit/hyperactivity disorder (13.7%), oppositional defiant disorder (13.2%), social phobia (10.7%), and dysthymia (10.5%). Demographic results are consistent with data from national samples and large psychopharmacology trials involving depressed adolescents. CONCLUSIONS: The Treatment for Adolescents With Depression Study provides a large, diverse, and representative sample of depressed adolescents that highlights the complexity of major depressive disorder in adolescents and provides a rich source for explicating the effects of moderator and mediator variables on baseline psychopathology and treatment outcome.

Adolescent↗

TNM T3a renal cell carcinoma: adrenal gland involvement is not the same as renal fat invasion.

PURPOSE: Upper pole tumors with direct extension into the adrenal gland are currently staged as pT3a tumors in the 1997 TNM staging system. To determine whether the clinical behavior of pT3a adrenal tumors differs from that of tumors with perinephric fat invasion (also stage pT3a) a retrospective analysis was performed. MATERIALS AND METHODS: Of 1,087 patients who underwent nephrectomy 27 were identified with direct adrenal involvement and 187 were identified with perinephric fat or renal sinus involvement. Variables and outcomes analyzed in each group included the percent of patients with metastatic disease at presentation, lymph node involvement, Eastern Cooperative Oncology Group score, response to immunotherapy, and median and overall survival using Kaplan-Meier curves. RESULTS: Median survival for patients with pT3a disease and perinephric or renal sinus fat involvement was 36 months with a 36% 5-year cancer specific survival rate. In contrast, patients with adrenal gland invasion had significantly worse survival at a median of 12.5 months and a 0% 5-year cancer specific survival rate (p <0.001), which was similar to median survival of those with stage pT4 disease (11 months). CONCLUSIONS: Upper pole tumors with direct extension into the adrenal gland predict significantly worse survival than similarly staged tumors with fat invasion and they have a prognosis similar to that of stage pT4 disease. While these data await external validation, consideration should be given to re-categorizing tumors with direct adrenal gland involvement as stage pT4 or in a subcategory such as pT4a.

Adipose Tissue↗

Is renal sinus fat invasion the same as perinephric fat invasion for pT3a renal cell carcinoma?

PURPOSE: Perinephric and renal sinus fat invasion are classified as pT3a renal cell carcinoma (RCC) according to the 2002 American Joint Committee on Cancer. We investigated the prognostic significance of each of these pathological features using a cohort of pT3a patients. MATERIALS AND METHODS: Between 1970 and 2002, 205 patients without direct adrenal invasion underwent nephrectomy for pT3a clear cell RCC. The associations of fat invasion with death from RCC were evaluated using Cox proportional hazards regression models. RESULTS: Of the 162 patients with perinephric fat invasion and 43 patients with renal sinus fat invasion 95 (59%) and 31 (72%), respectively, died of RCC. Patients with renal sinus fat invasion were 63% more likely to die of RCC compared with those with perinephric fat invasion (RR 1.63, 95% CI 1.09-2.46, p=0.018). In addition, the risk of death persisted in multivariate analysis after adjusting for regional lymph nodes and distant metastases (RR 1.91, 95% CI 1.26-2.89, p=0.002) and after adjusting for the Mayo Clinic SSIGN (stage, size, grade and necrosis) score (RR 1.90, 95% CI 1.25-2.88, p=0.003). CONCLUSIONS: Our results indicate that clear cell tumors invading the renal sinus fat are more aggressive than tumors with perinephric fat involvement. We believe both of these features should be individually assessed during routine pathological examination. External validation is needed before suggesting a change to the TNM staging system.

Adipose Tissue↗

An international otology database.

There are many reports in the literature on the outcome of ear surgery. However, it is difficult to make comparisons from these reports because of a lack of uniformity in the way in which outcomes are reported. At the same time, the general public expects doctors to provide them with information regarding the benefits and risks of surgery. Many ear surgeons will not be able to provide this information because few have an up-to-date database. A group of otologists in Europe has attempted to establish a common otology database. The aim is to create a framework whereby surgeons in Europe can contribute to a common ear database using a web-based system. The proposed methodology involves two levels of data entry. Level 1 is a minimal database where the main outcomes are included. Level 2 is a comprehensive database where detailed information on pathologies, risk factors, and surgical procedures is also recorded. As both databases share the same core data, clinicians using database 1 can still compare their outcomes with those using database 2. Clinicians will be able to input and retrieve ear data onto or from the web-based database. There has already been an international consensus on the content of the common ear database. The website address is www.ear-audit.net. The international project has now been in operation for more than 6 months, and Ear UK has already given its endorsement. The founder members include 27 otologists from 12 European countries. The cumulative outcome from this group of surgeons will be used as the benchmark for the purpose of comparative audit. These benchmark sites will be subjected to regular external validation. The web-based system is interactive and gives instant feedback to individual surgeons who wish to compare their results to the benchmark. Therefore, it can be a good learning tool for trainees or less experienced surgeons. The common data entry system also provides an opportunity for clinicians to collaborate in clinical research.

Databases, Factual↗

Feasibility and reliability of a mailed questionnaire to obtain visual analogue scale valuations for health states defined by the Health Utilities Index Mark 3.

To establish the generalizability (external validity) of the Health Utilities Index Mark 3 (HUI3) as a single-summary score generic outcome measure in numerous countries/subgroups (including children), repeated studies of community preferences should be performed in various settings. In performing multiple HUI3 studies, a mailed questionnaire approach, if feasible and reliable, might be substituted for oral interviews. In the present study, we assessed the feasibility and reliability of a mailed questionnaire approach originally developed for the EQ-5D, for the purpose of collecting Visual Analogue Scale (VAS) valuations from parents as surrogate responders for 65 pediatric HUI3 health states and for the state of being dead. Untransformed mean VAS scores of the health states and scores converted into preliminary Standard Gamble (SG)-utilities were compared with Canadian and French multiattribute utility estimates. A random sample of 1920 parents of schoolchildren (aged 4 to 13) received a mailed questionnaire. Each parent was asked to rate 6 HUI3 health states on a 0 to 100 VAS. Response was 70%. Mean completion time was 20 minutes (SD 9). The questionnaire was rated difficult by only 9%. The current format was, however, inappropriate for valuing the state of being dead. Interrater reliability of health state valuations was.87. Spearman's rank correlations, Pearson-R correlations and intra class correlation coefficients (ICCs) between untransformed VAS valuations and Canadian/French utility estimates were > or =.87. However, preliminary SG-utilities showed diminished ICCs (.71 to.72). The data support the feasibility and reliability of mailed HUI3 valuation questionnaires to a considerable extent, but further methodological studies regarding other formats and different populations are recommended.

Activities of Daily Living↗

Practical clinical trials for translating research to practice: design and measurement recommendations.

RATIONALE: There is a pressing need for practical clinical trials (PCTs) that are more relevant to clinicians and decision-makers, but many are unaware of these trials. Furthermore, such trials can be challenging to conduct and to report. OBJECTIVE: The objective of this study was to build on the seminal paper by Tunis et al (Practical clinical trials. Increasing the value of clinical research for decision making in clinical and health policy. JAMA. 2003;290:1624-1632.) and to provide recommendations and examples of how practical clinical trials can be conducted and the results reported to enhance external validity without sacrificing internal validity. KEY ISSUES: We discuss evaluating practical intervention options, alternative research designs, representativeness of samples participating at both the patient and the setting/clinician level, and the need for multiple outcomes to address clinical and policy implications. CONCLUSIONS: We provide a set of specific recommendations for issues to be reported in PCTs to increase their relevance to clinicians and policymakers, and to help reduce the gap between research and practice.

Clinical Trials as Topic↗

A rapid, fully automated, molecular-based assay accurately analyzes sentinel lymph nodes for the presence of metastatic breast cancer.

OBJECTIVE: To develop a fully automated, rapid, molecular-based assay that accurately and objectively evaluates sentinel lymph nodes (SLN) from breast cancer patients. SUMMARY BACKGROUND DATA: Intraoperative analysis for the presence of metastatic cancer in SLNs from breast cancer patients lacks sensitivity. Even with immunohistochemical staining (IHC) and time-consuming review, alarming discordance in the interpretation of SLN has been observed. METHOD: A total of 43 potential markers were evaluated for the ability to accurately characterize lymph node specimens from breast cancer patients as compared with complete histologic analysis including IHC. Selected markers then underwent external validation on 90 independent SLN specimens using rapid, multiplex quantitative reverse transcription-polymerase chain reaction (QRT-PCR) assays. Finally, 18 SLNs were analyzed using a completely automated RNA isolation, reverse transcription, and quantitative PCR instrument (GeneXpert). RESULTS: : Following analysis of potential markers, promising markers were evaluated to establish relative level of expression cutoff values that maximized classification accuracy. A validation set of 90 SLNs from breast cancer patients was prospectively characterized using 4 markers individually or in combinations, and the results compared with histologic analysis. A 2-marker assay was found to be 97.8% accurate (94% sensitive, 100% specific) compared with histologic analysis. The fully automated GeneXpert instrument produced comparable and reproducible results in less than 35 minutes. CONCLUSIONS: A rapid, fully automated QRT-PCR assay definitively characterizes breast cancer SLN with accuracy equal to conventional pathology. This approach is superior to intraoperative SLN analysis and can provide standardized, objective results to assist in pathologic diagnosis.

Biomarkers, Tumor↗