Biomedical subjects

Jayawant N Mandrekar

Publications and source records attributed to Jayawant N Mandrekar.

At least 19 recordsLinked to original sources

PubMed2006

Incidence and outcome of cervical artery dissection: a population-based study.

BACKGROUND: Incidence rates for internal carotid artery dissection (ICAD) have been reported to be 2.6 to 2.9 per 100,000, but reliable epidemiologic data for vertebral artery dissection (VAD) are not available. OBJECTIVE: To determine the incidence rate of cervical artery dissection (CAD) in a defined population. METHODS: With IRB approval, we used the medical record linkage system of the Rochester Epidemiology Project to identify all patients diagnosed with spontaneous ICAD and VAD for the period of 1987-2003 in Olmsted County, MN. RESULTS: Of 48 patients with CAD, there were 32 patients with ICAD and 18 patients with VAD. In Olmsted County, the average annual incidence rate for ICAD was 1.72 per 100,000 population (95% CI, 1.13 to 2.32) and for VAD 0.97 per 100,000 population (95% CI, 0.52 to 1.4). The average annual incidence rate for CAD was 2.6 per 100,000 population (95% CI, 1.86 to 3.33). The most frequently encountered symptoms in CAD were head or neck pain (80%), cerebral ischemia (TIA or infarct) (56%), and Horner syndrome (25%). Good outcome (defined as modified Rankin score of 0 to 2) was seen in 92% of patients. No recurrence of dissection was observed during a mean 7.8 years of follow-up. CONCLUSIONS: Internal carotid artery dissection was detected approximately twice as frequently as vertebral artery dissection in the overall study, but in the latter half of the study period, vertebral artery and internal carotid artery dissection incidence rates were equivalent. The majority of cervical artery dissection patients in the community have excellent outcome, and contrary to many tertiary referral series, re-dissection is rare.

Adult↗

PubMed2006

Detection of HIV-1 proviral DNA with the AMPLICOR HIV-1 DNA Test, version 1.5, following sample processing by the MagNA Pure LC instrument.

BACKGROUND: The AMPLICOR HIV-1 DNA Test, version 1.5 (AMP HIV-1 DNA 1.5), is a new commercially available PCR assay for the detection of human immunodeficiency virus type 1 (HIV-1) proviral DNA in human whole blood. OBJECTIVE: This study evaluates the performance characteristics of the assay following automated sample processing by the MagNA Pure LC instrument (MP). STUDY DESIGN: Analytical sensitivity and reproducibility were assessed by testing replicate HIV-1 DNA dilution panels over 5 days. Clinical sensitivity and specificity were studied among 28 HIV-1 DNA-positive clinical specimens, 60 specimens from healthy blood donors, and 63 specimens from HIV-1-seropositive patients with HIV-1 RNA plasma levels ranging from <50 to >100,000 copies/mL. RESULTS: Following MP sample processing, the assay yielded an analytical sensitivity (95% detection rate) of 66.3 copies/mL (95% CI, 50.7-106.8), with clinical sensitivity and specificity of 100%. CONCLUSIONS: MP is a reliable, labor-saving platform capable of processing specimens for AMP HIV-1 DNA 1.5. When combined with MP sample processing, AMP HIV-1 DNA 1.5 is a sensitive and reproducible assay for the detection of HIV-1 DNA in clinical whole blood specimens. However, the current AMP HIV-1 DNA 1.5 kit configuration may result in inefficient utilization of reagents.

Adolescent↗

PubMed2006

Simplified PCR protocols for INNO-LiPA HBV Genotyping and INNO-LiPA HBV PreCore assays.

BACKGROUND: INNO-LiPA HBV Genotyping (LiPA HBV GT) and INNO-LiPA HBV PreCore (LiPA HBV PC) are commercially available assays for hepatitis B virus (HBV) characterization. These assays are labor-intensive and may be prone to exogenous DNA contamination due to their use of nested PCR amplification procedures and lack of contamination control measures. OBJECTIVE: Standardized, single-round INNO-LiPA PCR amplification protocols incorporating uracil N-glycosylase and automated sample processing by the MagNA Pure LC instrument were evaluated. STUDY DESIGN: HBV standards containing 10,000, 1000, 100, 10, and 0 IU/mL were analyzed to determine the analytical sensitivity and reproducibility of these modified procedures. One hundred clinical serum specimens with viral titers ranging from 390 to 16,900,000 IU/mL were tested by modified LiPA HBV GT, while 34 specimens with viral titers ranging from 378 to 11,600,000 IU/mL were tested by modified LiPA HBV PC. RESULTS: Modified LiPA HBV GT and LiPA HBV PC each yielded analytical sensitivities of 100% at an HBV DNA level of 1000 IU/mL and 90% at a level of 100 IU/mL. Among clinical specimens, success rates for both INNO-LiPA procedures were > or =94%. CONCLUSIONS: Both modified INNO-LiPA procedures were sensitive and reproducible, with improved efficiency and suitability for routine laboratory use.

DNA, Viral↗

PubMed2006

Factor instability of clinical teaching assessment scores among general internists and cardiologists.

CONTEXT: We are unaware of studies examining the stability of teaching assessment scores across different medical specialties. A recent study showed that clinical teaching assessments of general internists reduced to interpersonal, clinical teaching and efficiency domains. We sought to determine the factor stability of this 3-dimensional model among cardiologists and to compare domain-specific scores between general internists and cardiologists. METHODS: A total of 2000 general internal medicine and cardiology hospital teaching assessments carried out from January 2000 to March 2004 were analysed using principal factor analysis. Internal consistency and inter-rater reliability were calculated. Mean item scores were compared between general internists and cardiologists. RESULTS: The interpersonal and clinical teaching domains previously demonstrated among general internists collapsed into 1 domain among cardiologists, whereas the efficiency domain remained stable. Internal consistency of domains (Cronbach's alpha range 0.89-0.93) and inter-rater reliability of items (range 0.65-0.87) were good to excellent for both specialties. General internists scored significantly higher (P<0.05) than cardiologists on most items except for 4 items that more accurately assessed the cardiology teaching environment. CONCLUSIONS: We observed factor instability of clinical teaching assessment scores from the same instrument administered to general internists and cardiologists. This finding was attributed to salient differences between these specialties' educational environments and highlights the importance of validating assessments for the specific contexts in which they are to be used. Future research should determine whether interpersonal domain scores identify superior teachers and study the reasons why interpersonal and clinical teaching domains are unstable across different educational settings.

Cardiology↗

PubMed2006

Quantification of hepatitis B virus (HBV) DNA with a TaqMan HBV analyte-specific reagent following sample processing with the MagNA pure LC instrument.

TaqMan hepatitis B virus (HBV) analyte-specific reagent (ASR; Roche Molecular Systems, Inc., Branchburg, NJ) is designed for the quantification of HBV DNA in serum or plasma. The performance characteristics of TaqMan HBV ASR following automated sample processing with the MagNA Pure LC instrument (MP; Roche Applied Science, Indianapolis, IN) were evaluated in this study. Analytical sensitivity and precision were assessed with commercially available HBV standards, while clinical serum specimens from HBsAg-seropositive patients and healthy blood donors were used to determine clinical sensitivity, specificity, and correlation with other commercially available assays. Analytical studies yielded a limit of detection of 2.4 IU/ml, with good linearity and correlation (R(2) = 0.9958) with expected HBV DNA titers over a wide range (6.0 x 10(0) to 2.1 x 10(8) IU/ml). Clinical sensitivity and specificity of the assay combined with automated sample processing were both 100%. Comparison of TaqMan HBV ASR and VERSANT HBV DNA 3.0 assay (bDNA; Bayer HealthCare LLC, Tarrytown, NY) results among clinical specimens yielded good correlation (R(2) = 0.9237), with a mean difference in titer of -0.213 log(10) IU/ml (95% confidence interval, -0.678 to 1.10 log(10) IU/ml). The overall test failure rate was 2.0% among 204 clinical serum specimens tested. Total time required for MP sample processing and automated postelution handling of 24 samples was 224 min, with 57 min of actual hands-on time. MP is a reliable, labor-saving platform suitable for use with TaqMan HBV ASR, providing sensitive and accurate quantification of HBV DNA levels over a range of 8 log(10) IU/ml.

DNA, Viral↗

PubMed2006

Breast lesions: evaluation with US strain imaging--clinical experience of multiple observers.

PURPOSE: To prospectively determine the accuracy of using an ultrasonographic (US) strain imaging technique known as lesion size comparison to differentiate benign from malignant breast lesions. MATERIALS AND METHODS: Institutional Review Board approval and patient informed consent were obtained for this HIPPA-compliant study. US strain imaging was performed prospectively for 89 breast lesions in 88 patients. Lesions were imaged by using freehand compression and a real-time strain imaging algorithm. Five observers obtained manual measurements of lesion height, width, and area from B-mode and strain images. By using these size measurements, individual observer and group performances were assessed by using the area under the receiver operating characteristic curve (A(z)). The performance of a single size parameter versus that of a combination of size parameters was evaluated by using univariate and multivariate logistic regression. RESULTS: Group A(z) values showed that width ratio and area ratio yielded the best results for differentiating benign and malignant breast lesions, and they were not statistically different from one another (P = .499). For the group, the performance of area and width, which was superior to that of height and aspect ratio, was statistically significant for all cases (P < .011) except for those that compared area with aspect ratio (P = .118). By using a group threshold of 1.04 for width ratio and 1.13 for area ratio, the sensitivity and specificity of the technique were 96% and 21%, respectively, for width and 96% and 24%, respectively, for area. The best observer achieved a sensitivity of 96% and a specificity of 61% by using the area ratio. For all but one observer, combined size parameters did not improve observer performance (P > .258). Significant interobserver performance variability was observed (P < .001). CONCLUSION: Results suggest that US strain imaging has the potential to aid diagnosis of breast lesions. However, manually tracing lesion boundaries for size ratio differentiation in a busy clinical setting did not match the diagnostic performance levels previously reported. Focusing on measurements of lesion width, along with additional observer training or automated processes, may yield a suitable method for routine clinical application.

Adult↗

PubMed2006

Patient outcomes after vestibular schwannoma management: a prospective comparison of microsurgical resection and stereotactic radiosurgery.

OBJECTIVE: The best management for patients with small- to medium-sized vestibular schwannomas (VS) is controversial. METHODS: : A prospective cohort study of 82 patients with unilateral, unoperated VS less than 3 cm undergoing surgical resection (n = 36) or radiosurgery (n = 46). Patients undergoing resection were younger (48.2 yr versus 53.9 yr, P = 0.03). The groups were similar with regard to hearing loss, associated symptoms, and tumor size. The mean follow-up period was 42 months (range, 12-62 mo). RESULTS: Normal facial movement and preservation of serviceable hearing was more frequent in the radiosurgical group at 3 months (P < 0.001), 1 year (P < 0.001), and at the last follow-up examination (P < 0.01) compared with the surgical resection group. Patients undergoing surgical resection had a significant decline in the following subscales of the Health Status Questionnaire 3 months after surgery: physical functioning (P = 0.006), role-physical (P < 0.001), energy/fatigue (P = 0.02), and overall physical component (P = 0.004). Patients in the surgical resection group continued to have a significant decline in the physical functioning (P = 0.04) and bodily pain (P = 0.04) subscales at 1 year and in bodily pain (P = 0.02) at the last follow-up examination. The radiosurgical group had no decline on any component of the Health Status Questionnaire after the procedure. The radiosurgical group had lower mean Dizziness Handicap Inventory scores (16.5 versus 8.4, P = 0.02) at the last follow-up examination. There was no difference in tumor control (100 versus 96%, P = 0.50). CONCLUSION: Early outcomes were better for VS patients undergoing stereotactic radiosurgery compared with surgical resection (Level 2 evidence). Unless long-term follow-up evaluation shows frequent tumor progression at currently used radiation doses, radiosurgery should be considered the best management strategy for the majority of VS patients.

Cohort Studies↗

PubMed2005

The relationship between histopathological features of progressive supranuclear palsy and disease duration.

Progressive supranuclear palsy (PSP) is a distinct clinicopathological entity characterized by neurofibrillary tangles, tufted astrocytes, threads and oligodendroglial coiled bodies. These four lesions are distributed in varying densities throughout subcortical and brainstem structures. There is no data regarding the relationship of disease duration to lesion burden severity in PSP. We report the results of analysis of semiquantitative data collected as part of the diagnostic evaluation on 97 cases of 'pure' PSP, submitted to the Society of PSP Brain Bank. Surprisingly, the data suggests that in PSP as duration of illness increases there is a decrease in oligodendroglial tau burden.

Aged↗

PubMed2005

Outcome of prosthetic joint infection in patients with rheumatoid arthritis: the impact of medical and surgical therapy in 200 episodes.

BACKGROUND: Prosthetic joint infection in patients with rheumatoid arthritis is a serious complication of total joint arthroplasty. Little information is available on the outcome of medical and surgical treatments of prosthetic joint infection in patients with rheumatoid arthritis. METHODS: We conducted a retrospective analysis of all patients with rheumatoid arthritis and a total hip or total knee arthroplasty infection evaluated at Mayo Clinic (Rochester, MN) between 1 January 1969 and 31 December 1995. RESULTS: A total of 200 first episodes of prosthetic joint infection in 160 patients with rheumatoid arthritis were diagnosed during the study period. Thirty-seven percent of prosthetic joint infection episodes were due to Staphylococcus aureus. Of these episodes, 23% and 19% were treated with debridement and retention of components and 2-stage exchange, respectively. The type of surgical procedure was the only analyzed clinical variable that was associated with treatment failure (P < .001). Rates of 5-year survival free of treatment failure for patients with prosthetic joint infection episodes treated with debridement and retention of components, 2-stage exchange, and resection arthroplasty were 32% (95% confidence interval [CI], 21%-49%), 79% (95% CI, 66%-93%), and 61% (95% CI, 49%-74%), respectively. CONCLUSIONS: S. aureus is the most common pathogen among patients with rheumatoid arthritis with prosthetic joint infection. Two-stage exchange was used in only 19% of the prosthetic joint infection episodes among patients with rheumatoid arthritis during the study period, but it was associated with the best outcome. The variable most strongly associated with the outcome was the type of surgical procedure.

Adult↗

PubMed2005

Prosthetic vascular graft infection: a risk factor analysis using a case-control study.

OBJECTIVES: Several factors have been anecdotally reported to increase the risk of prosthetic vascular graft infection (PVGI), a serious complication with high mortality and limb amputation rates. The goal of this study is to confirm purported risk factors using a well-designed statistical model. METHODS: Patients undergoing vascular graft placement at Mayo Clinic Rochester between January 1, 1982 and December 31, 2002 were retrospectively evaluated, excluding redo cases. PVGI cases had to meet one of the following criteria: perigraft air or fluid >8 weeks postoperatively, positive Gram stain or cultures of graft or perigraft material, intraoperative gross purulence, failure of graft incorporation, or exposed graft. Each case had two controls matched for age, gender and date of surgery. Duration of follow-up for a given control had to be at least equal to the time to infection of the corresponding case. Demographic and other clinical data were collected for each patient. RESULTS: Fifty-one cases and 102 controls met the inclusion criteria. Median age was 68 years. Staphylococcal species were identified in 45% of the total number of cases, and 60% of cases with a recovered organism. Univariate analysis identified groin incision, wound complication and wound infection as significant risk factors for PVGI (p<0.005 for all three factors). After adjusting for age and surgery date, multivariate analysis confirmed the statistical significance of groin incision and wound infection as risk factors for PVGI. CONCLUSIONS: This is the first published risk factor analysis that includes statistical evaluation in a case-control study of PVGI. Groin incision, wound complication, and wound infection are significantly associated with developing PVGI. These findings will assist in identifying patients at increased risk of developing subsequent infection. SUMMARY: In order to confirm purported risk factors of prosthetic vascular graft infections (PVGI), a well designed case-control study was conducted at Mayo Clinic, Rochester, MN. Univariate and multivariate analyses of 51 cases and 102 controls identified three statistically significant risk factors for the development of PVGI: groin incision, wound complication, and wound infection.

Adult↗

PubMed2005

Intra-venous digital subtraction angiography: an alternative method to intra-arterial digital subtraction angiography for experimental aneurysm imaging.

Conventional intra-arterial digital subtraction angiography (IADSA), which necessitates surgical exposure and ligation of the femoral artery, is an invasive and expensive method of evaluation for experimental elastase-induced aneurysms in rabbits. The purpose of this study was to examine and validate intra-venous digital subtraction angiography (IVDSA) as an alternative to IADSA by comparing their diagnostic accuracies. We performed both IVDSA and IADSA for 24 elastase-induced saccular aneurysms in a rabbit model, 1 month following creation. Aneurysm sizes (neck, width and height) from both the IVDSA and IADSA procedures were evaluated and measured. Comparison of the aneurysm sizes between IVDSA and IADSA were performed with the Wilcoxon paired signed-rank test. All the aneurysms were seen clearly in both the IVDSA and IADSA techniques. Mean sizes of the IVDSA aneurysm neck, width and height were 3.41 +/- 0.80 mm, 3.61 +/- 0.93 mm and 8.07 +/- 2.11 mm, respectively. Mean sizes of the IADSA aneurysm neck, width and height were 3.43 +/- 0.80 mm, 3.66 +/- 0.92 mm and 8.16 +/- 2.25 mm, respectively. No significant difference was found in the sizes of the aneurysm neck, width and height between the two groups (P = 0.311, P = 0.086 and P = 0.258, respectively). IVDSA appears to be an alternative method for evaluating elastase-induced aneurysms in rabbits.

Angiography, Digital Subtraction↗

PubMed2005

Temporal trends in infective endocarditis: a population-based study in Olmsted County, Minnesota.

CONTEXT: Limited data exist regarding population-based epidemiologic changes in incidence of infective endocarditis (IE). OBJECTIVE: To evaluate temporal trends in the incidence and clinical characteristics of IE. DESIGN, SETTING, AND PATIENTS: Population-based survey using the resources of the Rochester Epidemiology Project of Olmsted County, Minnesota. One hundred seven IE episodes occurred in 102 Olmsted County residents between 1970 and 2000. The modified Duke criteria were used to validate the diagnosis of definite or possible IE. MAIN OUTCOME MEASURES: Incidence of IE, proportion of patients with underlying heart disease, and causative microorganisms and clinical characteristics. RESULTS: Age- and sex-adjusted incidence of IE ranged from 5.0 to 7.0 cases per 100,000 person-years during the study period and did not change significantly over time (P = .42 for trend). Infective endocarditis caused by viridans group streptococci was the most common organism-specific subgroup, with an annual adjusted incidence of 1.7 to 3.5 cases per 100,000; in comparison, IE due to Staphylococcus aureus had an annual adjusted incidence of 1.0 to 2.2 cases per 100,000. No time trend was detected for either pathogen group (P = .63 and P = .66, respectively). An increasing temporal trend was observed in the proportions of prosthetic valve IE cases (P = .09). Among people with underlying heart disease, there was an increasing temporal trend in mitral valve prolapse (P = .04) and a decreasing trend in rheumatic heart disease (P = .08). However, the absolute numbers were small. There was no time trend in rates of valve surgery or 6-month mortality during the study period (P = .97 and P = .59, respectively). CONCLUSIONS: In this community-based temporal trend study, we found no substantial change in the incidence of IE over the past 3 decades. Viridans group streptococci continue to outnumber S aureus as the most common causative organisms of IE in this population.

Adult↗

PubMed2005

Correlation of histopathologic findings with clinical outcome in necrotizing fasciitis.

BACKGROUND: Necrotizing fasciitis is an uncommon disease with high morbidity and mortality rates. Little is known about the role of histopathologic examination in disease prognosis. METHODS: A retrospective study was conducted to determine what correlations, if any, exist between the histopathologic features of resected tissue in patients with necrotizing fasciitis and clinical outcome. RESULTS: Eighty-two cases of necrotizing fasciitis that occurred between January 1990 and December 2002 were identified. Histopathologic findings were available for review in 63 cases. A novel histopathologic classification scheme, based on hematoxylin-eosin and Gram stain results, was developed. The classification scheme included 3 stages: stage I, characterized by an intense neutrophilic response and an absence of bacteria in infected tissue; stage II, characterized by the presence of a moderate-to-severe neutrophilic response and positive Gram stain results or by minimal to absent neutrophilic response with a negative Gram stain result; and stage III, characterized by the presence of few or no polymorphonuclear leukocytes and a Gram stain result positive for bacteria during histopathologic examination. Patients with stage I findings had a significantly lower risk of death than patients with stage III findings (7.1% vs. 47%; odds ratio [OR], 0.1; 95% confidence interval [CI], 0.01-0.8; P=.03). Patients with stage II findings had a significantly lower mortality rate than patients with stage III findings (14.2% vs. 47%; OR, 0.2; 95% CI, 0.04-0.9; P=.04). Due to the small number of deaths (n=11) in patients for whom histopathologic examination of resected tissue was performed, multivariate analysis was not done. CONCLUSIONS: Results of this study suggest that histopathologic findings may correlate with clinical outcome in cases of necrotizing fasciitis. Because the histopathologic scheme is based on results of commonly available stains, it could be easily adopted for use in other institutions that could further evaluate its usefulness as a prognostic tool.

Adolescent↗

PubMed2005

Predictors of blood pressure control in patients with diabetes and hypertension seen in primary care clinics.

BACKGROUND: Blood pressure (BP) is not well controlled in the majority of patients with both diabetes and hypertension. This study was designed to identify predictors of BP control in patients with both diabetes and hypertension who are seen in primary care clinics. METHODS: This retrospective study was conducted by identifying a cohort of patients diagnosed with diabetes before January 1, 2000 (inception) who met predefined criteria for hypertension at inception and who received primary care in the ensuing 3-year study period (January 1, 2000, to February 31, 2002). Using the mean of all BP values between January 1, 2002, and December 31, 2002, subjects were divided into two groups: those with controlled BP and those with uncontrolled BP. The distribution of clinical predictors was compared between the two groups. Independent predictors were identified using multivariate logistic regression. RESULTS: Predictors of poor BP control were as follows: 1) isolated systolic hypertension at inception (OR= 0.62, CI = 0.47 to 0.82); 2) uncontrolled BP at inception (OR = 0.71, CI = 0.55 to 0.93); 3) use of oral hypoglycemic drugs versus diet and exercise alone or insulin use (OR = 0.73, CI = 0.56 to 0.95); 4) use of three or more antihypertensive drugs (OR = 0.74, CI = 0.56 to 0.97); and 5) older age (OR = 0.98, CI = 0.97 to 0.99). Predictors of better control were 1) use of nitrates (OR = 1.82, CI = 1.26 to 2.64); 2) history of coronary heart disease (OR = 1.47, CI = 1.08 to 2.00); and 3) at least one annual visit to subspecialist physician (OR = 1.43, CI = 1.09 to 1.88). CONCLUSIONS: Patients with both diabetes and hypertension who are older, have isolated systolic hypertension, use oral hypoglycemic drugs, or use three or more antihypertensive drugs should be targeted for better BP control. The roles of nitrate medication and subspecialist physicians in achieving better BP control needs further study.

Aged↗

PubMed2005

Use of complementary and alternative medical therapies by patients referred to a fibromyalgia treatment program at a tertiary care center.

OBJECTIVE: To evaluate the frequency and pattern of complementary and alternative medicine (CAM) use in patients referred to a fibromyalgia treatment program at a tertiary care center. PATIENTS AND METHODS: Patients referred to the Mayo Fibromyalgia Treatment Program between February 2003 and July 2003 were invited on their initial visit to participate in a survey regarding CAM use during the previous 6 months. An 85-question survey that addressed different CAM domains was used. RESULTS: Of the 304 patients invited to participate, 289 (95%) completed the survey (263 women and 26 men). Ninety-eight percent of the patients had used some type of CAM therapy during the previous 6 months. The 10 most frequently used CAM treatments were exercise for a specific medical problem (48%), spiritual healing (prayers) (45%), massage therapy (44%), chiropractic treatments (37%), vitamin C (35%), vitamin E (31%), magnesium (29%), vitamin B complex (25%), green tea (24%), and weight-loss programs (20%). CONCLUSION: CAM use is common in patients referred to a fibromyalgia treatment program.

Adolescent↗

PubMed2005

The interpersonal, cognitive and efficiency domains of clinical teaching: construct validity of a multi-dimensional scale.

BACKGROUND: We are unaware of any hypothesis-driven studies showing that teaching assessments are comprised solely of interpersonal and cognitive domains. Moreover, previous teaching assessments have been biased by heterogeneous samples of evaluators. Consequently, we investigated the construct validity of faculty assessments comprised of interpersonal and cognitive domains, utilising evaluations obtained from resident doctors on an internal medicine hospital service. METHODS: A total of 1000 inpatient evaluations were completed on 60 general internal medicine faculty members. Education theory supported a 2-dimensional, 14-item scale. Principal factor analysis was used to explore the scale's dimensionality. Internal reliability and interobserver agreement were determined. Relationships between domains and instructor characteristics were also examined. RESULTS: Principal factor analysis revealed interpersonal, clinical teaching and efficiency domains. Internal reliabilities of all domains are high (alpha > 0.90). Interobserver agreement is good (range 0.64-0.83). In the interpersonal domain there is a trend towards higher scores for lower ranking faculty. Significant findings are higher overall scores in the interpersonal domain (P < 0.001), higher scores for assistant professors in the interpersonal domain (P = 0.008) and higher scores for male than female faculty in the interpersonal (P = 0.041) and clinical teaching (P = 0.008) domains. CONCLUSIONS: Clinical teaching evaluations are reducible to interpersonal, clinical teaching and efficiency domains. Evidence for construct validity includes predicted domains and high internal and interobserver reliabilities. Utilising a homogenous sample of evaluators minimised variance. Interestingly, lower ranking faculty scored higher in the interpersonal domain, suggesting that lower ranking faculty may focus more attention on teaching activities than full professors do.

Clinical Medicine↗

PubMed2005

What is the validity evidence for assessments of clinical teaching?

BACKGROUND: Although a variety of validity evidence should be utilized when evaluating assessment tools, a review of teaching assessments suggested that authors pursue a limited range of validity evidence. OBJECTIVES: To develop a method for rating validity evidence and to quantify the evidence supporting scores from existing clinical teaching assessment instruments. DESIGN: A comprehensive search yielded 22 articles on clinical teaching assessments. Using standards outlined by the American Psychological and Education Research Associations, we developed a method for rating the 5 categories of validity evidence reported in each article. We then quantified the validity evidence by summing the ratings for each category. We also calculated weighted kappa coefficients to determine interrater reliabilities for each category of validity evidence. MAIN RESULTS: Content and Internal Structure evidence received the highest ratings (27 and 32, respectively, of 44 possible). Relation to Other Variables, Consequences, and Response Process received the lowest ratings (9, 2, and 2, respectively). Interrater reliability was good for Content, Internal Structure, and Relation to Other Variables (kappa range 0.52 to 0.96, all P values < .01), but poor for Consequences and Response Process. CONCLUSIONS: Content and Internal Structure evidence is well represented among published assessments of clinical teaching. Evidence for Relation to Other Variables, Consequences, and Response Process receive little attention, and future research should emphasize these categories. The low interrater reliability for Response Process and Consequences likely reflects the scarcity of reported evidence. With further development, our method for rating the validity evidence should prove useful in various settings.

Education, Medical↗

PubMed2005

Evaluation of the COBAS TaqMan HCV test with automated sample processing using the MagNA pure LC instrument.

The COBAS TaqMan HCV Test (TaqMan HCV; Roche Molecular Systems Inc., Branchburg, N.J.) for hepatitis C virus (HCV) performed on the COBAS TaqMan 48 Analyzer (Roche Molecular Systems) currently relies on a manual sample processing method. Implementation of an automated sample processing method would facilitate the clinical use of this test. In this study, we evaluated the performance characteristics of TaqMan HCV following automated sample processing by the MagNA Pure LC instrument (MP; Roche Applied Science, Indianapolis, Ind.). The analytical sensitivity of TaqMan HCV following sample processing by MP was 8.1 IU/ml (95% confidence interval, 6.1 to 15.2). The assay showed good linearity (R(2) = 0.99) across a wide range of HCV RNA levels (25 to 5 x 10(6) IU/ml), with coefficients of variation ranging from 10% to 46%. Among 83 clinical specimens, the sensitivity and specificity of TaqMan HCV were 100% and 95%, respectively, when compared to the COBAS AMPLICOR hepatitis C virus test, version 2.0 (COBAS AMPLICOR; Roche Molecular Systems), with TaqMan HCV detecting two more HCV RNA-positive specimens than COBAS AMPLICOR. Both specimens were confirmed to be HCV RNA positive by the VERSANT HCV RNA qualitative test (Bayer HealthCare LLC, Tarrytown, N.Y.). There was also strong correlation (R(2) = 0.95) and good agreement between the results from TaqMan HCV and the VERSANT HCV RNA 3.0 assay (bDNA) (Bayer HealthCare LLC) among a group of 93 clinical specimens. The MP is a versatile, labor-saving sample processing platform suitable for reliable performance of TaqMan HCV.

Automation↗