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PubMed2000

Release of metal in vivo from stressed and nonstressed maxillofacial fracture plates and screws.

OBJECTIVES: To analyze the release of metal into the adjacent tissues from stressed and nonstressed titanium and stainless steel miniplates and screws. STUDY DESIGN: Two miniplates were inserted into the cranial vaults of 12 beagle dogs while they were under general endotracheal anesthesia. One miniplate was shaped to fit the curvature of the skull (control). Another miniplate, made of the same material, was bent in a curve until the midpoint was raised 3 mm above the ends. Screws were inserted and tightened until the plate conformed to the skull curvature, creating stresses in the system. Four animals (2 each, having titanium or stainless steel plates and screws) were killed after 4, 12, and 24 weeks. Metallosis of adjacent soft tissues was assessed qualitatively. Miniplates and screws were removed, and adjacent soft tissue and bone was excised. Titanium, iron, chromium, nickel, and aluminum levels were assayed by ultraviolet/visible light and atomic absorption spectrophotometry. Nonparametric statistical methods were used for data analysis. RESULTS: There was no clear relationship between pigmentation of soft tissue adjacent to the miniplates and screws and the concentrations of metal present. The data did not demonstrate any consistent differences in the concentrations of metallic elements next to stressed and nonstressed (control) miniplates and screws of either material. CONCLUSION: Stresses arising through poor contouring of miniplates do not appear to influence the extent of release of metal into the adjacent tissues.

Aluminum↗
PubMed2000

Cherubism: a 36-year long-term follow-up of 2 generations in different families and review of the literature.

OBJECTIVE: To clarify the relationships between the varying clinical or radiographic features of cherubism. STUDY DESIGN: Nonparametric statistics were used in a long-term follow-up of 18 patients through 2 generations from 6 Danish families. RESULTS: The radiographic grade of cherubism was significantly related to sex, maximal buccal bone expansion, course of cherubism, and number of aplasia or ectopic impacted teeth, but it was not related to families. Normal dentition in nonaffected regions was present or was obtained in 14 of 14 patients (age, >14 years). Surgical treatment did not provoke growth of lesional tissue in 22 of 22 cases. Radiographically, the bone structure in the lesional areas was related to age in all grades of cherubism: new bone formation in radiolucent areas (age, >20 years), normal bone structure with multilocular sketches (age, 32 to 39 years), and completely normal bone structure (age, >41 years), also found in 7 of 7 carriers of cherubism (age, >32 years). CONCLUSIONS: This group analysis verifies the knowledge of cherubism previously based on cumulative reviews of findings in single-family and case reports.

Adolescent↗
PubMed2002

Relation of sleep state to hypoxemic episodes in ventilated extremely-low-birth-weight infants.

OBJECTIVE: To determine whether hypoxemic episodes in ventilated extremely-low-birth-weight infants correlate with specific behavioral states. STUDY DESIGN: Three-hour video-electroencephalography-polysomnography was performed on 13 ventilated extremely-low-birth-weight infants with mean postconceptional age of 28.3 weeks. The electroencephalogram was scored for discontinuity. Rapid eye movements, body, head, and limb movements were scored from synchronized video. Sleep states were defined from electroencephalography, rapid eye movements, and movement criteria. Nonparametric statistics were used to test for differences in the proportion of time hypoxemic (oxygen saturation </=85%) between behavioral states. RESULTS: The proportions of time hypoxemic were 0.6% during quiet sleep, 4.4% during active sleep, 10.7% during indeterminate sleep, and 16.7% during arousal. There was a significant overall difference between the states (P =.004) and a significant difference between active sleep and indeterminate sleep in a pairwise comparison (P =.001). CONCLUSIONS: Higher proportions of hypoxemia were found during indeterminate sleep and arousal compared with active sleep and quiet sleep. We speculate that motor activity during sleep disruption could prevent effective mechanical delivery of ventilator breaths and contribute to episodes of hypoxemia. Our results suggest that strategies promoting uninterrupted sleep cycling analogous to the intrauterine state could improve ventilatory stability.

Female↗
PubMed2000

Improving walking ability and ankle brachial pressure indices in symptomatic peripheral vascular disease with intermittent pneumatic foot compression: a prospective controlled study with one-year follow-up.

PURPOSE: Intermittent pneumatic foot compression (IPC(foot)) augments arterial leg inflow. It has been suggested that prolonged use of impulse leg compression at home might ameliorate claudication caused by peripheral vascular disease by improving collateral circulation. The purpose of this study was to determine the effect of IPC(foot) treatment on claudication distance and arterial hemodynamics in patients with intermittent claudication caused by peripheral vascular disease. METHODS: Thirty-seven patients with stable intermittent claudication were admitted to this prospective controlled study. Of these, 25 patients received IPC(foot) (>4 hr/d) for 4.5 months (group 1), and the other 12 patients acted as control patients (group 2). Both groups were advised to exercise unsupervised for a minimum of 1 hour daily and received aspirin (75 mg/d). Groups were matched for age, sex, risk factors, claudication distances, and ankle pressures at baseline. In each patient, initial claudication distance (ICD), absolute claudication distance (ACD), resting ankle brachial index (r-ABI), ankle brachial pressure index after exercise (p-eABI), and popliteal artery volume flow were measured at day 0, 2 weeks, and 1, 2, 3, and 4.5 months. On completion of the treatment period (4.5 months), both groups continued with aspirin (75 mg/d) and unsupervised exercise and were re-examined after 12 months. Data analysis is based on nonparametric statistics, the Wilcoxon signed ranks test, and the Mann-Whitney test for intragroup and intergroup comparisons, respectively. Results are expressed as median and interquartile ranges. RESULTS: Over the 4.5 months of active treatment, (1) median ICD in group 1 increased by 146% (P <.001), from 78 m (interquartile range, 65-102 m) at baseline to 191.5 m (interquartile range, 127-254 m); ICD did not significantly increase in group 2; (2) median ACD in group 1 improved by 106% (P <.001), from 124 m (interquartile range, 100-160 m) to 255 m (interquartile range, 149-398 m); no significant changes were documented in group 2; (3) median r-ABI in group 1 rose by 18% (P <.001), from 0.57 (interquartile range, 0.48-0.62) to 0.67 (interquartile range, 0.64-0.70); no improvement was noted in group 2; (4) median p-eABI in group 1 rose by 110% (P <.001), from 0.21 (interquartile range, 0.07-0.27) to 0.44 (interquartile range, 0. 36-0.52); no changes were noted in group 2; and (5) median popliteal artery volume flow in group 1 improved by 36% (P <.001), from 100 mL/min (interquartile range, 59-163 mL/min) to 136 mL/min (interquartile range, 99.5-173.4 mL/min); no significant changes were found in group 2. At 4.5 months, ICD, ACD, r-ABI, and p-eABI in group 1 were all significantly better than those in group 2 (P <.01). Twelve months' posttreatment, walking ability and ABIs in group 1 were not statistically different from those at 4.5 months and remained significantly better than those of control subjects. CONCLUSION: Intermittent pneumatic foot compression used at home for 4.5 months increases claudication distance by over 100%. Associated increases in r-ABI by 18%, p-eABI by 110%, and arterial calf inflow by 36% suggest an improved collateral circulation. Maximum benefit seems to be offered over the initial 3 months. Treatment benefits are maintained 1 year after treatment. A multicenter study is indicated to quantify actual benefits and to demonstrate cost effectiveness.

Aged↗
PubMed2006

Qi-training and immunological parameters: a cross-sectional study.

This article examined the effects of qi-training on peripheral T lymphocyte concentrations in a cross-sectional study involving three groups of subjects: normal healthy subjects (n = 22) and two groups of qi trainees (group Q1: qi-training for 1-12 months, n = 52; and group Q2: qi-training for >12 months, n = 63). Nonparametric statistical tests revealed significant differences between the groups in TH/TS/C ratio (p < .001) and in the ratio of memory TH lymphocytes (CD45RA-) to naïve TH lymphocytes (CD45RA+) (p < .001). These findings suggest that qi-training modulates peripheral T lymphocyte concentrations. However, the functional modulation of T helper lymphocytes should be tested in a larger population and compared with other interventions.

Adolescent↗
PubMed2006

Is there any difference in the effects of Qi therapy (external Qigong) with and without touching? A pilot study.

The aim of this study was to evaluate differences in the effects of Qi therapy without touching or with touching on anxiety, mood, neurohormones, and cellular immune function. Twenty-four healthy male subjects were randomly assigned to either QTN (n = 12) or QTT (n = 12). They received Qi therapy (external Qigong) without touching (QTN) or with touching (QTT). Nonparametric statistical tests revealed no significant differences between the effects of QTN and QTT (all p > .05). Separate Wilcox signed rank tests for each intervention revealed significant effects on anxiety, alertness, depression, fatigue, tension, cortisol levels, and NK cell cytotoxicity for both QTN and QTT, and on neutrophil function for QTN only. These findings suggest that there are few differences between the effects of QTN and QTT. However, the reproducibility of the findings should be tested with multiple sessions, and long-term follow-up tests.

Adult↗
PubMed1998

Recovery and rehabilitation following subarachnoid haemorrhage. Part I: Outcome after inpatient rehabilitation.

BACKGROUND AND PURPOSE: Although subarachnoid haemorrhage (SAH) is a subtype of stroke, functional outcome following rehabilitation for SAH must be considered distinct from that of cerebral infarction because of the younger age and the difference in pathology and resultant neurologic deficits. The purposes of this study were to: (1) describe the demographic and clinical characteristics of SAH patients receiving rehabilitation; (2) describe functional outcomes following inpatient rehabilitation; and (3) investigate possible relationships between patient characteristics and functional outcomes. METHODS: Retrospective chart review of SAH patients admitted to inpatient rehabilitation. Functional Outcomes rated by the Functional Independence Measures (FIM). Analysis with descriptive and nonparametric statistics. RESULTS: Eighty patients with SAH admitted to a rehabilitation unit with a mean age of 54 years. Fifty-seven had identified aneurysms as a cause of SAH. Seventy-four subjects (93%) presented with Hunt and Hess grades of 3-5. The median length of stay was 26 days in acute care and 49 days in rehabilitation. Seventy patients (88%) were discharged home. The mean admission FIM was 59.5 and mean discharge FIM 91.0. The FIM efficiency (aggregate change in FIM/day) was 0.62/day and the average rate of FIM gain 0.97 points/day. Hydrocephalus negatively influenced outcome (p = 0.05). There was a trend for subjects with worse Hunt and Hess scores at onset to have poorer discharge FIM scores. CONCLUSION: SAH patients receiving inpatient rehabilitation make functional gains, although the rate of gain is less than for TBI or stroke. These SAH patients represent a subgroup with more severe SAH at onset than the total population of SAH survivors. The presence of hydrocephalus negatively impacts on outcome. Further detailed study of functional and neuropsychological outcome in SAH survivors is needed.

Activities of Daily Living↗
PubMed2001

Clinical outcomes and patient perceptions of acupuncture and/or massage therapies in HIV-infected individuals.

This paper uses an innovative methodology to evaluate clinical outcomes and patient perceptions of acupuncture and massage therapies in an HIV medical outpatient setting. Using a quasi-experimental retrospective case control design, treatment subjects were matched by intake date and CD4 count with non-treatment subjects. All subjects had equal opportunity to access HAART therapies and other standard treatments for HIV. There were three treatment groups: acupuncture-only (n = 8), massage-only (n = 34) and acupuncture-and-massage (n = 21). Pre-treatment and post-treatment measures were compared within groups, and treatment and non-treatment group clinical outcomes were compared with each other. Using nonparametric statistical analysis, it was found that the means of the treatment groups' differences in pre- and post-CD4 counts showed improvement when compared with the non-treatment control group's pre- and post-CD4 counts. Treatment subjects were then interviewed and asked to rate their experiences of the therapies; the subjective experience was very positive. The reasons for these findings may be complex, including the possibility that some people may choose to manage their disease more aggressively, and may select a range of treatments. While no large claims are made for this study, these findings may be of interest both to clinicians and funders of acupuncture and/or massage therapies.

Acupuncture Therapy↗
PubMedDate not supplied

Limitations in application of Spearman's rank correlation to bioaerosol sampling data.

Bioaerosol sampling from various building sites, some of which were subjected to water damage and microbial growth, provided the opportunity to evaluate current recommendations for interpreting bioaerosol sampling data. Data from the ambient environment, a control building, and areas known to have microbial contamination were used as source data for random simulations. The simulations generated two comparison zones from microbial data from the same environment as a test model to identify the failure rate for Spearman's rank correlation. The results of the simulation indicated a failure rate approaching 60%, depending on the number of samples assigned to each zone by the simulation. The simulations indicated that nonparametric statistical treatment of bioaerosol data as currently recommended for building assessment purposes has limitations. An inordinately high Type II error (failure to reject a null hypothesis which is actually not true) is especially apparent when there are small numbers of samples. For example, in applying this methodology to clearance air sampling, a work zone subjected to removal of all moldy materials and a thorough particulate cleaning would still have a significant chance of failure solely due to the variability of the data, if individual samples are evaluated to identify "localized" contamination. This is significant with regard to the number of samples collected and the interpretation of individual samples in rendering evaluations of microbial contamination.

Aerosols↗
PubMed2005

The patient: a novel source of error in clinical temperature measurement using infrared aural thermometry.

INTRODUCTION: The vital signs are an important component of patient assessment. With respect to body temperature; there has been a move away from mercury-in-glass thermometers toward the relatively inexpensive, safer to use infrared tympanic, auricular, or ear thermometer. Although already in widespread use, the reliability of these devices has increasingly been called into question. Few studies, however, have considered that the problem might reside outside the device itself. OBJECTIVE: To investigate the correlation between left ear temperature and right ear temperature using an infrared tympanic thermometer (ITT). DESIGN: A prospective, single-blind trail with randomized assignment of the first ear to be assessed. SETTING/LOCATION: Welsh Institute of Chiropractic (WIOC), University of Glamorgan. SUBJECTS: One hundred and thirty two (132) asymptomatic subjects who were opportunistically sampled on entry into the WIOC. None of the subjects had any neurologic deficit, or any known underlying pathologic problems. All were students at the University of Glamorgan (age range, 18-48 years). A smaller sample of the same cohort was used on a separate occasion to compare ITTs from 2 different manufacturers using the same protocol. INTERVENTION: Measurement of ear (ear canal/tympanic) temperature bilaterally using an ITT. OUTCOME MEASURES: Bilateral asymmetry in ear canal temperature. Analysis consisted of nonparametric statistical tests, using Spearman's correlation for comparison and the Wilcoxon matched pairs test for differences. RESULTS: In 132 subjects who completed the main study, although a degree of correlation was found, the relationship did not extrapolate through zero. At temperatures more than 0.4 degrees C above or below 36.7 degrees C, there was a significant difference in temperature in the left compared with the right ear. Additionally, the left ear tended to register a lower temperature than the right ear at temperatures below 36.7 degrees C, whereas the left ear tended to read a higher temperature than the right ear above 36.7 degrees C. CONCLUSIONS: The authors suggest that clinicians consider measuring both ears, and take the greater of the readings to be a more accurate reflection of the patient's core temperature. The difference may perhaps even be related to the person's health. This change in methodology should increase the reliability of the measurement and go some way toward restoring confidence in the use of ITT devices.

Adult↗
PubMed1997

Overexpression of C/EBPbeta-LIP, a naturally occurring, dominant-negative transcription factor, in human breast cancer.

BACKGROUND: When cells fail to maintain a balance between proliferation, terminal differentiation, and programmed cell death, cancer often results. The CCAAT/enhancer-binding protein (C/EBP) family of transcription factors regulates many genes involved in the processes of proliferation and terminal differentiation. The messenger RNA for C/EBPbeta is translated into two major isoforms, LAP (liver-enriched activating protein) and LIP (liver-enriched inhibitory protein). LIP levels appear to be elevated in mouse mammary tumors but not in hyperplastic mammary tissues. We tested whether LIP expression is elevated in human breast cancer and whether elevated expression is associated with biologic predictors of the aggressiveness of the disease. METHODS: Homogenates of infiltrating ductal carcinoma specimens from 39 women were analyzed for C/EBPbeta protein content by western blot analysis, and the ratio of LAP to LIP in specimens containing high levels of LIP (i.e., levels approximately 15 times higher than those in tumor specimens that express little or no LIP) was also determined. Nonparametric statistical analyses were performed. RESULTS: LIP was present at high levels in nine of 39 specimens of infiltrating ductal carcinoma. Eight of the nine specimens of infiltrating ductal carcinoma that contained high levels of LIP were negative for estrogen receptor and progesterone receptor (ER-/PR-); all nine tumors were aneuploid and poorly differentiated, and eight of nine were highly proliferative. Of the tumors that contained LIP at low or nondetectable levels, six of 30 were ER-/PR-, 17 of 29 were aneuploid, eight of 27 were highly proliferative, and 11 of 30 were poorly differentiated. IMPLICATION: LIP expression should be evaluated further as a prognostic marker for patients with breast cancer.

Blotting, Western↗
PubMed2000

Genotype-phenotype relationships in U.S. melanoma-prone families with CDKN2A and CDK4 mutations.

BACKGROUND: Two genes have been implicated in the development of cutaneous malignant melanoma (CMM). CDK4 (the gene encoding cyclin-dependent kinase 4, an oncogene) has exhibited germline mutations found in only three melanoma-prone families to date. CDKN2A is a tumor suppressor gene that encodes p16 (which inhibits activity of the cyclin D1-CDK4 complex) with germline mutations detected in 10%-25% of melanoma-prone families, some of whom are also prone to pancreatic cancer. METHODS: We compared 104 CMM patients from 17 CDKN2A families and 12 CMM case subjects from two CDK4 families. We used nonparametric statistics to test for differences in median age at first CMM diagnosis, numbers of CMMs, and numbers of nevi. The three recurrent mutations were haplotyped. All P values were two-sided. RESULTS: The median age at CMM diagnosis (P =.70) and the median numbers of CMMs (P =.73) did not differ between CMM case subjects from CDKN2A versus CDK4 families. Assessment of CMM case subjects from CDKN2A families with and without pancreatic cancer revealed no statistically significant differences in median age at diagnosis (P =.80) or in tumor number (P =.24). There was, however, a statistically significant difference in age-adjusted median numbers of nevi (P =.004), and CMM case subjects from CDKN2A families without pancreatic cancer had greater numbers of nevi. Recurrent CDKN2A mutations were a change from valine to aspartic acid at codon 126 (n = 3) and from glycine to tryptophan at codon 101 (n = 3). Six CDKN2A families had pancreatic cancer. Both CDK4 families carried a mutation resulting in an arginine-to-cysteine substitution at codon 24. Analyses of recurrent CDKN2A and CDK4 mutations suggested common haplotypes. CONCLUSIONS: The recurrent CDKN2A mutations were observed in families with and without pancreatic cancer, which suggests that other factors may be involved in the development of pancreatic cancer. Despite hypothetical differences in the mechanisms of action between CDKN2A and CDK4, clinical factors were indistinguishable between CMM case subjects from CDKN2A versus CDK4 families.

Adolescent↗
PubMed1996

Patient-doctor communication in cross-national perspective. A study in Mexico.

The authors assessed the cross-national replicability previously used to study medical encounters in the United States by adapting them to Mexico. The main research questions focused on information-giving, gender and social class differences in communication, and attention to socioemotional concerns in primary encounters. Sixty-two primary care encounters were audiotaped. Questionnaires were translated into Spanish, then translated back into English. Coding and transcription techniques were taught to Spanish-speaking researchers. Measures of communication were treated as dependent variables and were related by nonparametric statistical analyses to characteristics of physicians, patients, and clinical settings. Doctors in Mexico spent an average of 2.1 minutes (+/- 1.7 standard deviation [SD]), or 16.7% (+/- 10.7 SD) of total interaction time, in information-giving. Mexican doctors asked an average of 27.3 questions per encounter (+/- 18.0 SD), whereas patients asked an average of 1.5 questions (+/- 2.0 SD). Substantial interphysician variability was observed in total time of interaction (Kruskal-Wallis analysis of variance, chi-square = 27.2, P = 0.000), physician time in information giving (chi-square = 16.4, P = 0.022), and physician questions (chi-square = 36.7, P = 0.000). Patient characteristics associated with physician information-giving included male gender (chi-square = 4.1, P = 0.04) and age (Kendall's tau-b = .17, P = 0.05) but not education (tau-b = .08, P = 0.41). Information-giving in public clinics did not differ from that in private practices (chi-square = 0.0, P = 0.91). A bootstrap approach to multiple nonlinear regression permitted additional analysis of physicians', patients', and situational characteristics in explaining measures of patient-doctor communication; this analysis further demonstrated the importance of interphysician variability in communicative behavior. Previous methods for studying patient-doctor communication can be adapted and replicated in a non-English-speaking society. With certain exceptions, findings from Mexico were similar to those obtained in the United States.

Adult↗
PubMed2000

Nursing home-to-nursing home transfers: prevalence, time pattern, and resident correlates.

OBJECTIVES: To characterize the time pattern of nursing home-to-nursing home transfers and assess which resident characteristics are associated with transfers. METHODS: Minimum Data Set assessments of all Maine and New York nursing home residents were obtained for 1994-1996. The hazard rate for nursing home transfers was estimated by nonparametric statistical techniques, censored at loss to follow-up. Comparisons of resident characteristics were made between those who transferred and those who stayed at their initial facility. RESULTS: Residents of Maine nursing homes were considerably more likely to transfer than were New York residents. Transfer rates declined during the first 2 years after admission and remained stable thereafter. Correlates of transfers were similar across states. Residents who transferred were more likely to be male, to be married, to be younger, to have better cognitive and physical health, to have Medicare or private payment sources (vs. Medicaid), and to have pressure ulcers. Rural location did not affect the likelihood of transfer. CONCLUSIONS: This study provides the most detailed information to date on the prevalence, timing, and correlates of nursing home transfers. These transitions occur most frequently early in the stay but continue at a lower rate even among long stayers. This information is useful for understanding lifetime dynamics of long-term-care utilization. Several barriers to mobility appear to be present (eg, less generous payment source, health limitations, and absence of a spouse). The higher transfer rates observed in Maine might imply that institutional or other factors limit the mobility of New York residents.

Aged↗
PubMed1999

The organizational context of non-lethal workplace violence: its interpersonal, temporal, and spatial correlates.

This article examines 993 violent incidents involving faculty, students, and staff that occurred at a highly ranked teaching and research university and its affiliated medical center. Violent incidents were included in the sample if they involved faculty, students, or staff, regardless of their specific location or context (i.e., whether they occurred on campus and/or off-campus and whether they occurred within the context of work or some other activity). The theoretical goal of the project was to compare work-related incidents with non-work-related incidents of interpersonal violence occurring in a single, multifunctioning, and professionally hierarchical organization. Data were collected over a 7-year period from three police departments (city, county, and university), university records, and criminal history records obtained from the state police. The coding protocol was developed to capture crime-scene information pertinent to each of the incidents. This included information about the victim, the perpetrator, the relationship between the victim and perpetrator, and the violent incident. The data were examined using nonparametric statistics and logistic regression to model predictive differences between the workplace and non-workplace incidents. The results suggest that the workplace incidents of violence differ from the non-workplace incidents according to their time, victim age, degree of victim injury, and whether the workplace is a medical location. The authors conclude that these differences are better explained by the movement of people in and out of the workplace who bring societal violence with them, rather than by a category or type of workplace violence.

Adult↗
PubMed2003

Evaluation of proprostate specific antigen for early detection of prostate cancer in men with a total prostate specific antigen range of 4.0 to 10.0 ng/ml.

PURPOSE: In contemporary screening populations a major drawback of prostate specific antigen (PSA) is its relative lack of specificity, especially in the range of 4 to 10 ng/ml, where prostate cancer is found 25% of the time. ProPSA is a derivative of free PSA (fPSA) consisting of the truncated forms (eg [-2]proPSA, [-4]proPSA or the full-length [-7]proPSA). There is increasing evidence that proPSA is associated preferentially with prostate cancer. The objective of this study was to determine whether proPSA can influence the detection of early prostate cancer. MATERIALS AND METHODS: Archival serum samples obtained from 93 men who underwent a systematic 12-core prostate biopsy (total PSA range 4.0 to 10.0 ng/ml) were assayed for percent free PSA, total PSA and the 3 forms of proPSA (Hybritech Tandem Assays Beckman Coulter Access, Beckman Coulter, Inc., Brea, California). Free PSA, the cumulative sum of individual proPSA forms ([-2], [-4] and [-7], or sum-proPSA) and derivatives were determined. Of the 93 men assessed 41 (44%) had evidence of prostate cancer (76% Gleason 5/6, 19% Gleason 7 and 5% Gleason 8). Prostate volume was measured at systematic 12-core biopsy for the detection of prostate cancer. Results were analyzed using univariate and multivariate logistic regression (LR) nonparametric statistical methods. RESULTS: Using univariate LR, fPSA, percent fPSA (%fPSA), percent sum-proPSA and prostate volume significantly (p <0.05) differentiated men with prostate cancer from those with benign disease. However, applying stepwise backward multivariate LR, total PSA, %fPSA and sum-proPSA were retained and generated a receiver operator characteristic curve with an area under the curve of 76.6%. At 90% sensitivity these 3 variables collectively achieved a specificity of 44% for the detection of prostate cancer. Individually, the 3 retained variables had a specificity of 23% (total PSA), 33% (%fPSA) and 13% (sum-proPSA). CONCLUSIONS: Sum-proPSA, total PSA and %fPSA in combination improve the specificity of early prostate cancer detection in men with a total PSA of 4 to 10 ng/ml compared with the results of individual PSA molecular forms measured.

Adenocarcinoma↗
PubMed2000

Nonparametric analysis of recurrent events and death.

This article is concerned with the analysis of recurrent events in the presence of a terminal event such as death. We consider the mean frequency function, defined as the marginal mean of the cumulative number of recurrent events over time. A simple nonparametric estimator for this quantity is presented. It is shown that the estimator, properly normalized, converges weakly to a zero-mean Gaussian process with an easily estimable covariance function. Nonparametric statistics for comparing two mean frequency functions and for combining data on recurrent events and death are also developed. The asymptotic null distributions of these statistics, together with consistent variance estimators, are derived. The small-sample properties of the proposed estimators and test statistics are examined through simulation studies. An application to a cancer clinical trial is provided.

Antineoplastic Agents, Alkylating↗
PubMed2006

Satisfaction with heart transplantation.

This research investigated patient satisfaction with heart transplantation (HT) 6 months after surgery. The authors explored whether HT patients would make the decision to have HT again and examined medical, psychosocial, and demographic factors associated with satisfaction or dissatisfaction in 257 HT recipients. Nonparametric statistics were used. Satisfaction with HT could be rated from 1 (not satisfied) to 10 (very satisfied). Eighty-seven percent of the patients were highly satisfied with HT 6 months after surgery (ratings of 8-10); 1% rated their satisfaction as low (1-3), and 12% rated it as moderate (4-7). Factors associated with less satisfaction with HT were: more symptom distress, greater disability, more stress, poor coping ability, feeling that the interventions of the HT team were not very helpful, less life satisfaction, and lower quality of life. Ninety-three percent indicated that they either definitely or probably would decide to have HT again; 7% responded "probably not" or "not sure." Factors associated with a negative perception of having another HT were: poor coping ability, less life satisfaction, lower quality of life, being male, and being married.

Adaptation, Psychological↗