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PubMed2001

Prevalence and determinants of erectile dysfunction in hemodialysis patients.

BACKGROUND: The prevalence of erectile dysfunction (ED) among patients with end-stage renal disease (ESRD) is not known. METHODS: A cross-sectional study was conducted to determine the prevalence of ED among a community-based hemodialysis (HD) population using a two-stage cluster random sampling design. The presence and severity of ED were assessed among 302 ESRD patients using the self-administered International Index of Erectile Function-5 (IIEF-5). Logistic regression was used to examine and test associations between ED and other medical conditions. RESULTS: The prevalence of any level of ED was 82% (95% CI, 76 to 87%) for all HD subjects. The prevalence of severe ED was 45% (CI, 36 to 55%). Subjects younger than 50 years had a prevalence of ED of 63% (CI, 53 to 71%), while in subjects 50 years or older, it was 90% (CI, 84 to 94%). A multivariable analysis demonstrated increasing age (50 to 59, OR = 2.04, 95% CI, 1.3 to 3.1; 60 to 69, OR = 5.5, 95% CI, 1.9 to 15.6) and diabetes (OR = 2.0, 95% CI, 1.2 to 3.3) to be independently associated with the presence of any level of ED. However, neither the subjects' age nor history of diabetes predicted the severity of ED among subjects with ED. The use of angiotensin-converting enzyme inhibitors (ACEIs) was inversely associated with ED (OR = 0.41, 95% CI, 0.17 to 0.98). Poor functional status (Karnofsky score or the Index of Physical Impairment) was not associated with ED. CONCLUSIONS: ED is extremely prevalent among HD patients. Increasing age, diabetes, and nonuse of ACEIs were associated with higher prevalence of ED. The high prevalence of ED was seen even among patients with good functional status.

Adult↗
PubMed1998

Longitudinal and cross-sectional variability in markers of joint metabolism in patients with knee pain and articular cartilage abnormalities.

OBJECTIVE: To determine the within- and between-patient variability in the concentrations of synovial fluid, serum and urine markers of joint tissue metabolism in a cohort of patients with knee pain and cartilage changes consistent with early-stage knee osteoarthritis. DESIGN: Samples of synovial fluid, serum, and urine were obtained from 52 patients on eight different occasions during 1 year, as part of a clinical trial in patients with cartilage abnormalities and knee pain. In joint fluid, aggrecan fragments were quantified by dye precipitation and enzyme-linked immunosorbent assay (ELISA), and matrix metalloproteinases-1 and -3, and tissue inhibitor of metalloproteinases-1 by sandwich ELISAs. In serum, keratan sulfate was quantified by ELISA. Type I collagen N-telopeptide cross-links in urine were determined by ELISA. RESULTS: The degree of cross-sectional variability in marker concentrations did not vary between the different sampling occasions, and did not differ between the periods of weeks 0 (baseline), 1-4 (treatment) and 13-26 (follow-up). Both between-patient and within-patient coefficients of variation varied for markers in different body fluid compartments, with the lowest variability for serum keratan sulfate, followed by urine type I collagen N-telopeptide crosslinks, and the highest for synovial fluid markers. For synovial fluid, aggrecan fragments showed the least variability, and matrix metalloproteinases the highest. One patient with septic arthritis showed a fivefold peak increase in joint fluid aggrecan fragment concentrations, while the concentration of matrix metalloproteinase-3 increased 100-fold. CONCLUSIONS: Molecular markers of joint tissue metabolism have been suggested as, for example, outcome measures for clinical trials of disease-modifying drugs in osteoarthritis. This report is the first to present data on between- and within-patient variability for such molecular markers in three different body fluid compartments in stable cohort of patients. The availability of such data enables calculations to determine the number of patients needed in prospective studies using these markers as outcome measures.

Adult↗
PubMed2000

The effect of cardiovascular health promotion on health behaviors in elementary school children: an integrative review.

This report provides on an integrative review of health promotion studies relevant to elementary school children published between 1986 and 1998. The 22 research articles represented several disciplines including public health and nursing. The studies varied in research design, sample characteristics, and approaches to health education. The most common interventions targeted behavioral risk factors for cardiovascular disease, but it also was evident from the literature that family and community involvement both played a significant role in health behaviors of children. Health promotion studies were under-represented in the nursing literature, a gap that creates an impetus to study children and families to identify the ways they learn primary preventive behaviors.

Cardiovascular Diseases↗
PubMedDate not supplied

The effect of recombinant equine growth hormone on the biomechanical properties of healing superficial digital flexor tendons in horses.

OBJECTIVE: To evaluate the effect of recombinant equine growth hormone (rEGH) on the in vitro biomechanical properties of healing superficial digital flexor tendon (SDFT) in horses. STUDY DESIGN: Completely randomized design. SAMPLE POPULATION: Twelve Standardbred horses, 3 to 7 years of age, with ultrasonographically normal forelimb SDFT. METHODS: One week after induction of collagenase (2,000 U) induced superficial flexor tendonitis, horses were randomly divided into groups of 6. One group was administered intramuscular rEGH (10 microg/kg/day for 1 week, then 20 microg/kg/day for 5 weeks), whereas the other group (control subjects) were administered an equivalent volume of saline (0.9% NaCl) solution. At the end of this 6-week treatment, horses were killed and one forelimb SDFT from each horse was harvested for biomechanical testing under uniaxial tension. Results were analyzed using an unpaired Student's t test; significance was set at P <or=.05. RESULTS: SDFT from horses treated with rEGH had significantly larger mean cross-sectional areas and lower mean values for ultimate and yield tensile stress, whereas tendons from the control group were biomechanically stiffer than those from the rEGH-treated horses. CONCLUSIONS: Administration of rEGH to horses for 6 weeks, 1 week after collagenase induced injury to the SDFT, resulted in a significant increase in tendon cross-sectional area, a concomitant reduction in ultimate and yield tensile stress, and reduced tendon stiffness. CLINICAL RELEVANCE: Using this model of tendonitis, rEGH had a negative effect on the biomechanical properties of equine SDFT in the early phases of healing. Based on our results, administration of rEGH to treat superficial flexor tendonitis cannot be recommended.

Animals↗
PubMedDate not supplied

Recombinant equine growth hormone does not affect the in vitro biomechanical properties of equine superficial digital flexor tendon.

OBJECTIVE: To evaluate the effect of recombinant equine growth hormone (rEGH) on the in vitro biomechanical properties of normal adult equine superficial digital flexor tendon (SDFT). STUDY DESIGN: Completely randomized design. SAMPLE POPULATION: Nine Standardbred horses, 6 to 9 years of age with ultrasonographically normal forelimb SDFT. METHODS: Six horses were administered intramuscular (IM) rEGH at 10 microg/kg/day for 1 week, and then 20 microg/kg/day for another 5 weeks; 3 horses (control subjects) were administered an equivalent daily volume of sterile water IM. Horses were killed at the end of the 6-week treatment period, and both forelimb SDFT were harvested and stored at -70 degrees C. In vitro biomechanical testing was performed under uniaxial tension. Results were analyzed using a general linear model of analysis of variance; significance was set at P <.05. RESULTS: There were no differences in cross-sectional area, maximal load at failure, yield load, ultimate and yield tensile strain, ultimate and yield tensile stress, or stiffness between tendons from control and treated horses. CONCLUSIONS: Administration of rEGH to adult Standardbred horses for 6 weeks had no detectable effect on the in vitro biomechanical properties of normal SDFT. CLINICAL RELEVANCE: Administration of rEGH does not modulate the in vitro biomechanical properties of SDFT from adult Standardbred horses.

Animals↗
PubMedDate not supplied

Fixation technique influences the monotonic properties of equine mandibular fracture constructs.

OBJECTIVE: To determine the optimal fixation technique for equine interdental space fractures by evaluating the biomechanical characteristics of 4 fixation techniques. STUDY DESIGN: In vitro randomized block design. SAMPLE POPULATION: Twenty-seven adult equine mandibles. METHODS: Mandibles with interdental osteotomies were randomly divided into 4 fixation groups (n = 6/group). Fixation techniques were the following: (1) dynamic compression plates (DCP), (2) external fixator (EF), (3) external fixator with interdental wires (EFW), and (4) intraoral splint with interdental wires (ISW). Three intact (nonosteotomized) mandibles were tested as controls. Mandibles were subjected to monotonic cantilever bending until failure. Angular displacement data (radians) were derived from continuously recorded gap width measurements provided by extensometers placed across the osteotomy site. Osteotomy gap width data (mm) at 50 and 100 Nm were selected for standardized comparison of gap width before the yield point and failure point, respectively of all constructs tested. Stiffness (Nm/radian), yield strength (Nm), and failure strength (Nm) were determined from bending moment-angular displacement curves and were compared using ANOVA with appropriate post hoc testing when indicated. Radiographs were obtained prefixation, postfixation, and posttesting. RESULTS: Bending stiffness, yield, and ultimate failure loads were greatest for intact mandibles. Among osteotomized mandibles, stiffness was greatest for DCP constructs (P <.05) and was not significantly different among EF, EFW, and ISW constructs. Yield load was greatest for ISW constructs (P <.05) and was not significantly different among DCP and EFW constructs. Yield and ultimate failure loads were lowest (P <.05) and osteotomy gap width at 50 and 100 Nm were greatest for EF constructs (P =.09 and P <.05, respectively). There was no significant difference in failure loads and osteotomy gap widths among DCP, EFW, and ISW constructs (P <.05). Failure occurred through the screw-bone interface (DCP), acrylic splint (ISW), acrylic connecting bar and/or pin-bone interface (EF, EFW), and wire loosening (EFW). All 3 intact mandibles fractured through the vertical ramus at its attachment to the testing apparatus. CONCLUSIONS: Among osteotomized mandibles, DCP fixation had the greatest stiffness under monotonic bending to failure; however, the relatively low yield value may predispose it to earlier failure in fatigue testing without supplemental fixation. Techniques using tension-band wiring (EFW and ISW) were similar to DCP constructs in yield, failure, and osteotomy displacement, whereas EF constructs were biomechanically inferior to all other constructs. CLINICAL RELEVANCE: DCP fixation is most likely the most stable form of fixation for comminuted interdental space fractures. However, for simple interdental space fractures, ISW fixation may provide adequate stability with minimal invasiveness and decreased expense. Tension-band wiring significantly enhances the strength of type II external skeletal fixators and should be used to augment mandibular fracture repairs.

Animals↗
PubMed1997

National Averages for Process and Outcome in Radiation Oncology: Methodology of the Patterns of Care Study.

The purpose of this article is to describe the methodology used by the Patterns of Care Study to conduct surveys of the practice of radiation oncology that not only provide national averages for process and outcome measures but also allow comparisons among important subgroups. The article describes how the sample design assures that these analyses are possible and presents methods used for data collection and analysis.

Journal Article↗
PubMedDate not supplied

[The hospital service misuse problem in orthopedics].

In a representative study for all German acute hospitals the amount of inappropriate (medically not necessary) patient care was estimated. The data material, sampling design, weighting technic and the appropriateness expert rating (retrospective, consent judging) was controlled. An overall proportion of inappropriate days of care of 18.45% were found but for orthopedic diseases this rate was 31.9% and even 37.7% for the younger than 60 orthopedic patients. Similar high rates for orthopedic diseases were found in US hospital studies of inappropriateness and should lead to an analysis of their reasons.

Bed Occupancy↗
PubMed2002

Tumor necrosis factor-alpha and interleukin-1beta levels in recurrent and persistent otitis media with effusion.

OBJECTIVE: Based on interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha levels in effusions, our goals were to specify either recurrent or persistent otitis media with effusion (OME) is a mid stage in the development of chronic disease and to identify the factors that have an influence on cytokine levels. STUDY DESIGN: Samples from groups with recurrent (n = 15) and persistent (n = 39) OME were assayed for IL-1beta and TNF-alpha. Children were also grouped with respect to age, sex, quality of effusion, and the presence of pharyngeal adenoid tissue. SETTING: Tertiary referral center. RESULTS: In recurrent and persistent OME groups, IL-1beta was higher than TNF-alpha (P < 0.01). IL-beta was higher in recurrent OME than in persistent OME (P < 0.05). CONCLUSION: Recurrent OME seems to be closer to the chronic stage of the disease relative to persistent OME in terms of higher IL-1beta levels. Each exacerbation of acute disease in recurrent otitis media is likely to be mediated by IL-1beta. SIGNIFICANCE: We were able to clarify that recurrent OME is a stage that occurs before chronic OME. Therefore, the prevention of acute attacks in recurrent disease would also impede long-term damage to the middle ear.

Age Factors↗
PubMed2000

Comparison of infrared spectroscopic and fluorescence depolarization assays for fetal lung maturity.

OBJECTIVE: Infrared spectroscopic analysis of amniotic fluid was recently shown to be a potential useful method for the determination of fetal lung maturity. Those studies used thin-layer chromatography as a reference method for the calibration of the infrared-based technique. However, thin-layer chromatography is compromised by large intra-assay and interlaboratory coefficients of variation. Therefore in this study we have used a reference method that is based on fluorescence depolarization, the TDx FLM II assay, to verify the sensitivity and precision of infrared spectroscopy for assessment of fetal lung maturity status. STUDY DESIGN: Samples of amniotic fluid were obtained by amniocentesis from 101 patients between the 24th and 40th weeks of pregnancy. Small volumes (35 microL) of amniotic fluid specimens were dried, and the infrared spectra were measured with a commercial infrared spectrometer. The fetal lung surfactant/albumin ratio was determined separately for each specimen with the TDx FLM II assay. The proposed infrared method was then calibrated and tested with a partial least-squares regression analysis to quantitatively correlate the infrared spectra with the surfactant/albumin ratios provided by the TDx FLM II assays. RESULTS: A total of 144 training spectra were used to build the partial least-squares calibration model. The correlation coefficient for the training set was excellent (r = 0.92), with an SE between infrared-predicted and reference surfactant/albumin ratios of 17 mg/g. The model was then validated on a set of 69 test spectra and yielded an SE of 14 mg/g (r = 0.86). The final partial least-squares model included the 900- to 1500-cm(-1) and 2800- to 3200-cm(-1) spectral ranges and 6 partial least-squares factors. CONCLUSION: Because the infrared-based fetal lung maturity measurements correlated well with assays from both of the current standard clinical techniques (thin-layer chromatography and fluorescence depolarization) and the procedure is less labor and training intensive, we concluded that infrared spectroscopy has the potential to emerge as the method of choice for prediction of fetal lung maturity from amniotic fluid analysis.

Albumins↗
PubMed2002

The effect of elective cesarean delivery and intrapartum infection on fetal lymphocyte activation and susceptibility to HIV infection.

OBJECTIVE: Mother-to-child transmission of the human immunodeficiency virus may be reduced with elective cesarean delivery before labor. Because immune activation enhances the human immunodeficiency virus infection, we hypothesized that fetal lymphocytes that are obtained at elective cesarean delivery may be less activated, therefore less susceptible to human immunodeficiency virus infection than cells that are obtained after normal spontaneous vaginal delivery at term. A second hypothesis was that intrapartum infection correlates with increased lymphocyte activation and susceptibility to human immunodeficiency virus infection. STUDY DESIGN: Samples were obtained after normal spontaneous vaginal delivery (n = 13), elective cesarean delivery (n = 12), chorioamnionitis (n = 5), and preterm labor (n = 6). Activation markers were measured by flow cytometry, and cord blood mononuclear cells were infected with the human immunodeficiency virus. RESULTS: Cell activation was comparable within the normal spontaneous vaginal delivery and elective cesarean delivery groups; there was no difference in susceptibility to in vitro human immunodeficiency virus infection. Intrapartum infection (chorioamnionitis, preterm labor) was associated with increased cell activation. Chorioamnionitis/preterm labor also tended to increase cord blood mononuclear cell susceptibility to human immunodeficiency virus infection. CONCLUSION: Labor did not activate fetal lymphocytes or alter susceptibility to human immunodeficiency virus infection compared with elective cesarean delivery. Intrapartum infection was associated with cell activation, and there was a trend toward increased susceptibility to human immunodeficiency virus infection. These data suggest that fetal lymphocyte activation correlates with susceptibility to human immunodeficiency virus infection and may account for the increased mother-to-child transmission of the human immunodeficiency virus that has been seen in association with chorioamnionitis and preterm labor.

Cesarean Section↗
PubMed2000

Mercury release from dental amalgam after treatment with 10% carbamide peroxide in vitro.

OBJECTIVES: The effect of 10% carbamide peroxide on mercury release from dental amalgams was assessed in vitro by using a cold-vapor atomic absorption Mercury Analyzer System. STUDY DESIGN: Samples of 4 commercial brands of dental amalgam, Megaloy (Dentsply/Caulk, Milford, Del), Mega+ (CFPM, Aulnaye, France), Nongama 2 (Silmet, Or Yehuda, Israel), and Valiant Ph.D. (Dentsply/Caulk, Milford, Del), were treated for 48 hours with 10% carbamide peroxide and compared with samples treated with phosphate buffer. RESULTS: Amalgam specimens exposed for 48 hours to 10% carbamide peroxide showed significantly higher concentrations of mercury in solution as compared with specimens treated with phosphate buffer (P <.001). Megaloy and Valiant Ph.D. yielded significantly higher mercury concentrations in solution than Mega+ and Nongama 2 (P <.001). Mega+ yielded significantly higher mercury concentrations in solution than Nongama 2 (P <.05). No significant differences were found in mercury concentrations in solution between Megaloy and Valiant Ph.D. CONCLUSIONS: Treatment with 10% carbamide peroxide bleaching agents caused an increase in mercury release from amalgam restorations, possibly increasing exposure of patients to its adverse effects. Amalgam brands differed in the amounts of mercury release after bleaching with carbamide peroxide.

Carbamide Peroxide↗
PubMed2001

"Red complex" (Bacteroides forsythus, Porphyromonas gingivalis, and Treponema denticola) in endodontic infections: a molecular approach.

OBJECTIVE: The "red complex," composed of Bacteroides forsythus, Porphyromonas gingivalis, and Treponema denticola, is implicated in severe forms of periodontal diseases. The purpose of this study was to assess the occurrence of the red complex in root canal infections through the use of a sensitive technique-the 16S rDNA-directed polymerase chain reaction (PCR). STUDY DESIGN: Samples were obtained from 50 necrotic pulps with periradicular pathosis. Ten cases were diagnosed as acute periradicular abscesses. DNA was extracted from the samples and analyzed with a PCR-based identification assay. RESULTS: At least 1 member of the red complex was found in 33 of 50 cases. T denticola, P gingivalis, and B forsythus were detected in 44%, 30%, and 26% of the cases, respectively. The red complex was found in 4 of 50 cases. No particular signs or symptoms were associated with the presence of these bacterial species. CONCLUSIONS: Despite what is indicated in reports with respect to marginal periodontitis, red complex bacteria-either singularly or collectively-was not associated with any particular pattern of clinical symptoms. However, because the bacterial species from the red complex are recognized oral pathogens, their occurrence in root canal infections suggests that they may play a role in the pathogenesis of periradicular diseases.

Adolescent↗
PubMed2002

Dialister pneumosintes can be a suspected endodontic pathogen.

OBJECTIVE: Dialister pneumosintes is a nonmotile, nonfermentative, non-spore-forming, obligately anaerobic, gram-negative bacillus that has been associated with some infections in the human body. A species-specific nested polymerase chain reaction assay was used to investigate the occurrence of D pneumosintes in primary root canal infections. STUDY DESIGN: Samples were collected from 32 teeth with carious lesions, necrotic pulps, and radiographic evidence of periradicular bone destruction. Twenty-two teeth were asymptomatic, and 10 cases were diagnosed as acute apical periodontitis. DNA extracted from the samples was initially amplified with universal 16S ribosomal DNA primers. A second round of amplification used the first polymerase chain reaction products to specifically detect D pneumosintes. RESULTS: This bacterial species was detected in 17 of 22 asymptomatic cases (77.3%) and in 4 of 10 root canals associated with acute apical periodontitis (40%). No relationship was found between the presence of this bacterial species and the occurrence of symptoms. In general, D pneumosintes was detected in 21 of 32 root canal samples (65.6%). CONCLUSION: This study is the first to report a high prevalence of D pneumosintes in root canal infections of humans. Because of this high prevalence and the apparent pathogenicity of the microorganism, we suggest the inclusion of D pneumosintes in the selected group of putative endodontic pathogens.

Acute Disease↗
PubMed2004

Neutrality, niches, and dispersal in a temperate forest understory.

A fundamental goal of ecology is to understand what controls the distribution and abundance of species. Both environmental niches and trade-offs among species in dispersal and competitive ability have traditionally been cited as determinants of plant community composition. More recently, neutral models have shown that communities of species with identical life-history characteristics and no adaptation to environmental niches can form spatial distribution patterns similar to those found in nature, so long as the species have a limited dispersal distance. If there is a strong correlation between geographic distance and change in environmental conditions, however, such spatial patterns can arise through either neutral or niche-based processes. To test these competing theories, we developed a sampling design that decoupled distance and environment in the understory plant communities of an old-growth, temperate forest. We found strong evidence of niche-structuring but almost no support for neutral predictions. Dispersal limitation acted in conjunction with environmental gradients to determine species' distributions, and both functional and phylogenetic constraints appear to contribute to the niche differentiation that structures community assembly. Our results indicate that testing a neutral hypothesis without accounting for environmental gradients will at best cause unexplained variation in plant distributions and may well provide misleading support for neutrality because of a correlation between geographic distance and environment.

Analysis of Variance↗
PubMed2002

High-throughput screening for evidence of association by using mass spectrometry genotyping on DNA pools.

To facilitate positional cloning of complex trait susceptibility loci, we are investigating methods to reduce the effort required to identify trait-associated alleles. We examined primer extension analysis by matrix-assisted laser desorptionionization time-of-flight mass spectrometry to screen single-nucleotide polymorphisms (SNPs) for association by using DNA pools. We tested whether this method can accurately estimate allele frequency differences between pools while maintaining the high-throughput nature of assay design, sample handling, and scoring. We follow up interesting allele frequency differences in pools by genotyping individuals. We tested DNA pools of 182, 228, and 499 individuals using 16 SNPs with minor allele frequencies 0.026-0.486 and allele frequency differences 0.001-0.108 that we had genotyped previously on individuals and 381 SNPs that we had not. Precision, as measured by the average standard deviation among 16 semidependent replicates, was 0.021 +/- 0.011 for the 16 SNPs and 0.018 +/- 0.008 for the 291381 SNPs used in further analysis. For the 16 SNPs, the average absolute error in predicting allele frequency differences between pools was 0.009; the largest errors were 0.031, 0.028, and 0.027. We determined that compensating for unequal peak heights in heterozygotes improved precision of allele frequency estimates but had only a very minor effect on accuracy of allele frequency differences between pools. Based on these data and assuming pools of 500 individuals, we conclude that at significance level 0.05 we would have 95% (82%) power to detect population allele frequency differences of 0.07 for control allele frequencies of 0.10 (0.50).

Alleles↗
PubMed2006

BEME systematic review: predictive values of measurements obtained in medical schools and future performance in medical practice.

BACKGROUND: Effectiveness of medical education programs is most meaningfully measured as performance of its graduates. OBJECTIVES: To assess the value of measurements obtained in medical schools in predicting future performance in medical practice. METHODS SEARCH STRATEGY: The English literature from 1955 to 2004 was searched using MEDLINE, Embase, Cochrane's EPOC (Effective Practice and Organization of Care Group), Controlled Trial databases, ERIC, British Education Index, Psych Info, Timelit, Web of Science and hand searching of medical education journals. INCLUSION & EXCLUSIONS: Selected studies included students assessed or followed up to internship, residency and/or practice after postgraduate training. Assessment systems and instruments studied (Predictors) were the National Board Medical Examinations (NBME) I and II, preclinical and clerkship grade-point average, Observed Standardized Clinical Examination scores and Undergraduate Dean's rankings and honors society. Outcome measures were residency supervisor ratings, NBME III, residency in-training examinations, American Specialty Board examination scores, and on-the-job practice performance. DATA EXTRACTION: Data were extracted by using a modification of the BEME data extraction form study objectives, design, sample variables, statistical analysis and results. All included studies are summarized in a tabular form. DATA ANALYSIS AND SYNTHESIS: Quantitative meta-analysis and qualitative approaches were used for data analysis and synthesis including the methodological quality of the studies included. RESULTS: Of 569 studies retrieved with our search strategy, 175 full text studies were reviewed. A total of 38 studies met our inclusion criteria and 19 had sufficient data to be included in a meta-analysis of correlation coefficients. The highest correlation between predictor and outcome was NBME Part II and NBME Part III, r = 0.72, 95% CI 0.30-0.49 and the lowest between NBME I and supervisor rating during residency, r = 0.22, 95% CI 0.13-0.30. The approach to studying the predictive value of assessment tools varied widely between studies and no consistent approach could be identified. Overall, undergraduate grades and rankings were moderately correlated with internship and residency performance. Performance on similar instruments was more closely correlated. Studies assessing practice performance beyond postgraduate training programs were few. CONCLUSIONS: There is a need for a more consistent and systematic approach to studies of the effectiveness of undergraduate assessment systems and tools and their predictive value. Although existing tools do appear to have low to moderate correlation with postgraduate training performance, little is known about their relationship to longer-term practice patterns and outcomes.

Clinical Competence↗
PubMed1988

Neurobehavioral effects of central nervous system prophylactic treatment of cancer in children.

This article reviews 41 studies of the effects of prophylactic CNS treatment on the neurobehavioral development of children with cancer. This research is classified according to studies of (a) children in treatment; (b) long-term survivors; and (c) longitudinal follow-ups of children from the time of diagnosis. Studies vary considerably in design, sample, and outcome variables, so firm conclusions regarding the morbidity of CNS prophylaxis are not currently possible. However, the studies do suggest that CNS prophylaxis does impair cognitive development, particularly when cranial radiation therapy is part of the treatment. There is also evidence of greater impairment in younger children and some suggestion of more frequent impairment of non-language skills relative to language skills. The possible relationships among age, radiation, and non-language cognitive skills may be linked to disruption of white matter CNS structures apparent on autopsy and cerebral tomography following treatment.

Adolescent↗