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PubMedDate not supplied

Fixed and dynamic equinus in cerebral palsy: evaluation of ankle function after multilevel surgery.

Multilevel surgery for gait improvement was performed on 29 ambulatory children with diplegic cerebral palsy. Patients were divided into two groups based on the presence of dynamic equinus (12 cases) and fixed equinus deformity (17 cases). Dynamic equinus deformities were not corrected surgically, and fixed deformities were corrected by intramuscular gastrosoleus lengthening. Ankle function was evaluated by clinical examination and gait analysis before surgery and a minimum of 3 years after surgery. Positive changes in ankle function were observed in both the groups. Conservative management of dynamic equinus deformities resulted in significant improvements in ankle function. Intramuscular lengthening of fixed equinus deformities does not cause a weakening of the muscle and improves static and dynamic function of the ankle.

Cerebral Palsy↗
PubMed1998

Outcome analysis of noninstrumented anterior cervical discectomy and interbody fusion in 348 patients.

STUDY DESIGN: Twenty-one outcome and outcome-relevant variables (fusion and patient satisfaction) were evaluated in a subset of 348 of 514 patients operated on by one surgeon during a 22-year period, using Cloward's anterior cervical discectomy and dowel interbody fusion. Minimum patient follow-up was 2 years; average length of follow-up was 5.2 years. This retrospective analysis is accompanied by a comprehensive review of the literature (1975-1996) of noninstrumented anterior cervical fusions, excluding fibular grafts alone in the interbody space. OBJECTIVES: To provide data on outcome (with regard to patient satisfaction and radiologically supported fusion) and risks of noninstrumented anterior cervical discectomy and fusion for intractable cervical nerve root and spinal cord compression symptoms at single or multiple levels, using the results from a single surgeon. METHODS: Three experienced spine radiologists determined fusion rates in one to five levels in 348 patients on the basis of the results of plain film analysis. Patient self-assessment was used to determine degree of patient satisfaction and other related variables. From a comprehensive review of the literature, 43 clinical reports meeting requirements for comparison of findings with those in the current study were selected from more than 1600 reports. RESULTS: The mean fusion rate for 348 patients in the current study ranged from 75% (multilevel) to 88% (one level; n = 202). The overall fusion rate was 83%. The persistent complication rate was 0.1%, and patient self-assessments showed that 78% were satisfied with the outcome and that 83% returned to work. The overall fusion rate for 2037 patients evaluated in the comprehensive literature review is 92%. CONCLUSIONS: Results of this study indicate that better outcome in noninstrumented anterior cervical discectomy and fusion is associated with solid fusion, fewer fused levels, nonsmoking patients, higher education levels, and absence of secondary economic gain. There was no correlation between fusion status and bone graft source or use of cervical collar.

Adult↗
PubMed2026

Prostate morcellation devices: a systematic review and meta-analysis of clinical outcomes and efficiency.

OBJECTIVE: To systematically evaluate the efficiency and safety of different prostate morcellators used during prostate enucleation for benign prostatic hyperplasia (BPH). METHODS: A systematic review was performed according to the Preferred Reporting Items for Systematic Review and Meta-analyses guidelines. PubMed/Medline, Scopus, and Web of Science were searched for studies published between October 2012 and May 2025. Studies reporting clinical outcomes of morcellators used during prostate enucleation were included. Primary outcome was morcellation efficiency (g/min). Secondary outcomes included intraoperative complications, device malfunction, and cost when available. Risk of bias (RoB) was assessed using the Risk Of Bias In Non-randomised Studies of Interventions (ROBINS-I), RoB 2 tool, and European Association of Urology case-series criteria. Random-effects meta-analyses and multilevel meta-regression adjusted for prostate volume were conducted. RESULTS: A total of 22 studies comprising 5980 patients were included, most undergoing holmium laser enucleation of the prostate. The most frequently evaluated devices were the Piranha™ (Richard Wolf GmbH, Knittlingen, Germany) and Lumenis VersaCut™ (Lumenis Ltd., Yokneam, Israel; 12 and 13 studies, respectively), followed by DrillCut™ (Karl Storz SE & Co. KG, Tuttlingen, Germany), MultiCut™ (Asclepion Laser Technologies GmbH, Jena, Germany), and Cyber Blade™ (Quanta System SpA, Milan, Italy) systems. Unadjusted weighted mean morcellation efficiency was 7.80 g/min (95% confidence interval [CI] 6.26-9.34 g/min) for Piranha, 4.70 g/min (95% CI 3.61-5.79 g/min) for VersaCut, 5.90 g/min (95% CI 3.16-8.64 g/min) for DrillCut, and 9.59 g/min (95% CI 4.78-14.39 g/min) for MultiCut. In volume-adjusted meta-regression using Piranha as reference, VersaCut remained significantly less efficient (-2.75 g/min; 95% CI -4.58 to -0.92 g/min; P = 0.003), with an even greater difference in prostates >70 mL (-4.34 g/min). Bladder mucosal injury was the most frequently reported complication; however, relatively rare across all devices. Meta-analysis demonstrated a significantly higher risk with VersaCut compared to Piranha (risk ratio 3.22, 95% CI 1.81-5.71), with low heterogeneity. CONCLUSION: This systematic review provides a contemporary clinical benchmark of the efficiency and safety of currently available prostate morcellators. Oscillating blade systems, particularly the Piranha morcellator, demonstrated higher morcellation efficiency and a more favourable safety profile than reciprocating blade devices, with the largest performance differences observed in patients with larger prostates.

Humans↗
PubMed2002

Role of individual and contextual effects in injury mortality: new evidence from small area analysis.

OBJECTIVE: To analyse the role of individual and contextual variables in injury mortality inequalities from a small area analysis perspective, looking at the data for the city of Barcelona (Spain) for 1992-98. SETTING: Barcelona (Spain). METHODS: All injury deaths in residents older than 19, which occurred in the period 1992-98 were included (n=4393). Age and sex specific mortality rates were calculated for each educational level and each cause of death (traffic injuries, falls, drug overdose, suicide, other injuries). The contextual variables included were the proportion of men unemployed, and the proportion of men in jail, in each neighbourhood. Multilevel Poisson regression models were fitted using data grouped by age, educational level, and neighbourhood for each sex. RESULTS: Death rates were higher in males, at the extremes of the age distribution (under 44 and over 74 years), and for lower educational levels. The results of the Poisson multilevel models indicate that inequalities by educational level follow a gradient, with higher risks for the population with no schooling, after having adjusted for the contextual variables of the neighbourhood. Such inequalities were more important in the youngest age group (20-34 years), as relative risk of 5.41 (95% confidence interval (CI) 3.9 to 7.4) for all injury causes in males and 4.38 (95% CI 2.3 to 8.4) in females. The highest relative risks were found for drug overdose. There was a contextual neighbourhood effect (the higher the deprivation, the higher the mortality) after having taken into account individual variables. CONCLUSION: The findings underscore the need to implement injury prevention strategies not only at the individual level taking into account socioeconomic position, but also at the neighbourhood level.

Adult↗
PubMed1976

2. The data base for rehabilitation services.

Rehabilitation is a long-term multidisciplinary, and outcome-oriented process, which requires a more complex data base than one derived from a strictly medical model of diagnosis, treatment, and cure. The rehabilitation data base must document need and potential for benefit, reasons for encounter, intensity of services, response to services in terms of outcome and durability of rehabilitation, and significant modifiers related to the individual and his environment that affect intake, outcome, and follow-through. Research has shown the potential value of functional indices as components of this data base and has illustrated approaches to their validation. A central question is whether a data base designed for patient care can also have utility for institutional management and policy formulation in view of differences in content, level of detail, and timing. Other problems that have become obvious in the past decade of experimentation at the Texas Institute for Rehabilitation and Research include the burden of data collection on professional and technical staff, cost effectiveness of data systems, validity and reliability, too much or irrelevant data in the system, and behavioral obstacles to new systems and their effective use. Despite these problems, multilevel information systems that can be expanded or contracted in detail and are designed to provide data of established utility are clearly needed in rehabilitation.

Activities of Daily Living↗
PubMed2004

The role of the Genial Bone Advancement Trephine system in conjunction with uvulopalatopharyngoplasty in the multilevel management of obstructive sleep apnea.

OBJECTIVES: The successful surgical management of obstructive sleep apnea (OSA) requires surgical procedures that address both retropalatal and retrolingual airway obstruction. The Genial Bone Advancement Trephine (GBAT) system is a new, 1-step system that allows for isolation and advancement of the genioglossus muscle via a guided trephine system. The purpose of this project was to describe our experience using the GBAT system to perform genioglossus advancement (GGA) in conjunction with uvulopalatopharyngoplasty (UPPP) in the surgical management of OSA. STUDY DESIGN: Retrospective analysis of 35 consecutive patients undergoing GGA using the GBAT system in conjunction with UPPP for the management of OSA during a 3-year period (1999 to 2002). RESULTS: Twenty-four patients had complete preoperative and postoperative polysomnographic data. A 70% reduction in the Respiratory Disturbance Index (RDI) and Apnea Index (AI) in the preoperative versus postoperative PSG (RDI, 52.9 +/- 17.1 versus 15.9 +/- 7.5; AI, 20.1 +/- 6.7 versus 6.1 +/- 4.5; P < or = 0.0001). The lowest oxygen desaturation increased from 80% to 88% (P = 0.0002), and the posterior airway increased from 7.9 to 12.6 mm (P < 0.0001). With a surgical cure defined as a greater than 50% reduction in the RDI and a final postoperative RDI of less than 20 events per hour, the true surgical cure rate was 67% (16 of 24 patients). CONCLUSIONS: The GBAT system performed in conjunction with UPPP can produce significant reductions in RDI and AI while improving the oxygen desaturation and enlarging the posterior airway space. The effective cure rates using the GBAT system are in agreement with previous reports in the literature using various GGA techniques. The GBAT may have some advantages in terms of simplicity and safety.

Adult↗
PubMed1993

Violence by and against women: a comparative and cross-national analysis.

Drawing from different kinds and levels of analysis, this article synthesizes current knowledge on women's violent offending and victimization cross-nationally. Individual-level data indicate characteristics and situations that put women at risk for violence within particular countries. Aggregate-level data concentrate on women's risks of violent encounters across nations and the societal-level factors that are associated with these risks. This multinational, multilevel approach reveals substantial gaps between our understanding of the types of encounters in which women are at greatest risk for violence and the societal correlates that predict gender distributions in violence across nations.

Adolescent↗
PubMed2003

Multilevel temperature-controlled radiofrequency therapy of soft palate, base of tongue, and tonsils in adults with obstructive sleep apnea.

OBJECTIVES/HYPOTHESIS: The concept of two-level pharyngeal collapse in patients with obstructive sleep apnea is too simplified. Aggressive multilevel surgeries addressing several airway segments, including skeletal surgery, demonstrate improved success rates. STUDY DESIGN: The study aimed to evaluate the safety and efficacy of multilevel radiofrequency application to soft palate, tonsils, and base of tongue in 16 white patients (mean age, 56.9 +/- 11.1 y; mean body mass index, 27.3 +/- 2.6 kg/m2) with obstructive sleep apnea. There was one dropout. Therapeutic effects after one treatment session were assessed 20.6 +/- 12.6 weeks postoperatively. Treatment outcome measurements were based on Epworth Sleepiness Scale, Likert scales, and polysomnography. METHODS: Every patient received 16 treatment sites with a total dose of 9750 J radiofrequency energy into soft palate, base of tongue, and tonsils. Success was defined as respiratory disturbance index equal to or less than 20 or at least 50% improvement if baseline respiratory disturbance index was less than 20. Statistical analysis was determined with the Spearman rank test. RESULTS: Mean score on Epworth Sleepiness Scale decreased from 11.1 to 8.2 (P =.0001). Of the patients, 53.3% reported improvement of their daytime sleepiness. Snoring was assessed with 10-point Lickert scale, and score decreased from 7.5 to 4.9 (P =.08). Mean respiratory disturbance index decreased from 32.6 +/- 17.4 to 22.0 +/- 15.0 (P =.003). By our definition of success, 5 of 15 patients (33%) have been treated successfully surgically and 4 of 15 (27%) had remarkable improvement after one treatment session; 1 patient (6.6%) demonstrated deterioration. There were two adverse effects, one superficial ulceration of the soft palate and one unilateral tonsillar abscess formation, with an overall complication rate of 13.3% for our patients and 0.41% for all treatment sites (n = 240). CONCLUSION: Moderate to severe obstructive sleep apnea usually requires multilevel pharyngeal surgery. Radiofrequency offers the potential of altering the upper airway on different sites.

Adult↗
PubMed2004

Income inequality at neighbourhood level and quality of life--a contextual analysis.

OBJECTIVE: Associations were examined between neighbourhood income inequality and neighbourhood socioeconomic deprivation on the one hand and (mental) health related quality of life (QoL) on the other, in Maastricht, the Netherlands. METHODS: Three different data sources were used: 1) neighbourhood socioeconomic indicators, 2) house prices per postal code area aggregated to an inequality measure at neighbourhood level, and 3) individual data measured in a family cohort study. Maastricht families with children aged approximately 11 years received questionnaires including the parents' QoL and family socioeconomic status (response rate: 60%). Multilevel analyses were conducted using neighbourhood level, family level, and individual level data. RESULTS: Income inequality at neighbourhood level was not associated with QoL, whereas socioeconomic deprivation was associated with environment-related QoL. CONCLUSION: The relative income hypothesis, according to which it is the contrast in deprivation rather than the absolute level of deprivation that influences health outcomes, does not hold at the neighbourhood level. Income inequality may only have an effect in larger areas containing sufficient socioeconomic contrast.

Adult↗
PubMed2006

Quality control using a multilevel logistic model for the Danish pig Salmonella surveillance antibody-ELISA programme.

In Denmark, the level of Salmonella infection in pig herds is monitored with a surveillance programme using an indirect antibody ELISA. Our purpose with the present study was to determine whether sample results from the programme were useful in the quality control of this ELISA. Test results from the year 2003, in which the laboratory experienced a technical problem with an automatic microtitre-plate washing machine, were examined statistically. We chose 3 months for the analysis: January, where the problem was moderate, June with the problem more serious, and November, where the problem had been solved. A logistic analysis was carried out with outcome 0 for a negative test result and 1 for a positive test result. Row and column on the microtitre plates, multiprobe robot, and their interactions were included as fixed effects, and date, plate, and slaughterhouse were included as random effects. Backward elimination was carried out using alpha=0.05 to achieve a final model for each month. The row and the column were significant in January and June, and a robot effect was also included in the model for January. In June, an interaction between row and column was identified. In November, none of the fixed effects was significant. Breaking the months January and June into shorter time intervals showed that the row and column effects were significant also when data were from only 1 week, whereas the robot main effect was not significant in most periods and the interaction effects were not significant throughout. Analysis of the test results from the wells with test samples gave good information on systematic errors across the microtitre plates, and severe errors appeared significant even when data from short time periods were used.

Animals↗
PubMed2005

Cervical spondylotic myelopathy: 10 years of prospective outcome analysis of anterior decompression and fusion.

BACKGROUND: Fifty-one patients with cervical spondylotic myelopathy (CSM) treated by anterior cervical corpectomy with fusion (ACWF) at our institution were included in a study during a period of 10 years to evaluate neurological, anatomical, and functional outcomes including satisfaction levels. METHODS: We have completed a prospective evaluation of 39 patients with spondylotic myelopathy submitted to ACWF during the period of 1989-2000. The data were analyzed for age, duration of symptoms, severity of preoperative neurological deficit, and single-level or multilevel compressive status looking for possible association with prognostic surrogate data and clinical outcome that were evaluated with the Nurick score and a survey of level of satisfaction. RESULTS: Of the 51 patients, 39 fullfilled the intended follow-up being 28 men (71.8%) and 11 women (28.2%). The average age was 63.5 years. Duration of symptoms ranged from 1 to 240 months (mean, 38.1 months). The mean preoperative Nurick scale score was 2.97; the mean postoperative score was 2.1. The most frequently involved vertebral body was C5 (71.7%). The follow-up period was longer than 18 months for all patients. Postoperative nonneurological complications occurred in 8 patients (15.6%). The mortality rate was 1.9% (n = 1). Postoperative results showed improvement in 25 patients (64.1%), no change in 13 (33.3%), and worsening in 1 (2.6%). The correlation coefficient of preoperative and postoperative Nurick scores was 0.733 (R(2) = 0.53). Of the 39 patients, 31 answered the questionnaire for quality of life-19 (61.2%) were very satisfied, 6 were satisfied (19.35%), and 6 were not satisfied (19.35%). CONCLUSION: Most patients (80.6%) were very satisfied or satisfied with the outcome and would decide again for the surgery (87%) if the results were previously known. Anterior cervical corpectomy with fusion was a reliable and rewarding procedure for CSM, with functional improvement in most patients. Excellent long-term outcome results in cervical fusion can be achieved without the use of hardware instrumentation.

Adult↗
PubMed2000

Image-processing algorithms for behavior analysis of group-housed pigs.

Computational algorithms of image processing were developed and evaluated to select, by motion detection, images of resting artificial pigs and to segment the pigs (mixture of black and white pigs) from their background. Motion detection of the pigs was implemented by detecting interframe differences of postural behavioral images. This algorithm combines the advantages of likelihood ratio method and shading model method and shows a stable performance under noisy and dynamic illumination conditions. Segmentation of the pigs from their background was implemented by employing multilevel thresholding and background reference techniques. The algorithm automatically determines the number of thresholds needed and produces satisfactory segmentation when both black and white pigs with different image intensities are present at the same time (the most complicated situation). The reference background image is updated so that temporal changes in illumination and/or spatial changes of the pen condition have little effect on the performance of image segmentation. The algorithm employs statistical models of the pigs and background and Bayes hypothesis testing to obtain and update the exposed portion of the reference background. Linear filters were used in this process for updating the parameters. These algorithms will serve as essential components for a novel, behavior-based, interactive approach to assess and control thermal comfort of group-housed pigs, which is expected to result in enhanced animal health and well-being.

Algorithms↗
PubMed2006

One-male units and clans in a colony of hamadryas baboons (Papio hamadryas hamadryas): effect of male number and clan cohesion on feeding success.

In the multilevel societies of hamadryas baboons, adult males can be attached to single one-male units (OMUs) or to clans containing several such OMUs. This paper examines the effect of male number and rivalry between males within a clan on their ability to compete for access to a clumped food resource. The data come from a study of a multilevel colony of hamadryas baboons (Papio hamadryas hamadryas) housed at the Madrid Zoo. The colony consisted of 12 harem-holding males and 40 sexually mature females, and was organized into five single OMUs and two clans (containing three and four OMUs, respectively). The top-ranking male of one of the clans was removed and later reintroduced, so the study involved an analysis of the composition of clans and OMUs and of the males' use of the feeding area across three study periods: preseparation, separation, and reintroduction. The findings reported indicate that both males and females derived clear advantages in the context of contest competition for access to clumped food if they were members of clans, because the males and females from large clans had a feeding advantage over those from smaller clans and single OMUs. Furthermore, rivalry among males within the clan reduced their ability to compete for food against males outside their clan. This paper provides empirical evidence for one of the potential advantages that hamadryas males may enjoy if they are attached to clans, and also provides empirical support for the general hypothesis that a large number of males in a group may provide fitness-related benefits to the group members, provided they are able to cooperate with each other.

Animals↗
PubMed2004

Religious attendance and depressive symptoms among community dwelling elderly in Taiwan.

BACKGROUND: The purpose of this study was to investigate the unique association between religious attendance and the prevalence of depressive symptoms among community dwelling elderly persons. METHODS: Employing a multilevel stratified sampling strategy, a total of 1000 subjects, aged 65-74 and living in Taiwan, were recruited for this interview survey during the year 2001. Aside from background information, the Taiwanese Depression Questionnaire (TDQ) and the Neighborhood Quality Index were used to assess degree of depression and its correlates. RESULTS: Altogether, 863 subjects (age, M = 69.4, SD = 2.7) had complete data for analysis; 215 (24.8%) had had depressive symptoms in the past week. Among them, those who were female, (OR = 2.17, 95% CI = 1.59-2.97), illiterate(OR = 2.42, 95% CI = 1.76-3.33), unemployed (OR = 1.80, 95% CI = 1.24-2.61), or not married (OR = 1.71, 95% CI = 1.22-2.38), or those who had less family income (OR = 1.84, 95% CI = 1.24-2.73), physical illness (OR = 2.68, 95% CI = 1.86-3.86), or less social capital (OR = 0.91, 95% CI = 0.88-0.94), were at higher risk of being depressed. Moreover, those (95.2% with religious belief ) who had not attended religious activities during the past 6 months were at higher risk of being depressed than those (100% with religious belief ) who had (OR = 2.63, 95% CI = 1.41-4.91). Multivariate logistic regression disclosed that those never attending religious activities were 2.70 times more likely to be depressed when compared to those who had, after taking into consideration sociodemographics and social capital. CONCLUSION: The attending of religious activities is a protective factor for geriatric depression.

Activities of Daily Living↗
PubMed1995

Fitting Weibull duration models with random effects.

Duration time models often should include correlated failure times, due to clustered data. These random effects hierarchical models sometimes are called "frailty models" when used for survival analyses. The data analyzed here involve such correlations because patient level outcomes (the times until graft failure following kidney transplantation) are observed, but patients are clustered in different transplant centers. We describe fitting such models by combining two kinds of software, one for parametric survival regression models, and the other for doing Poisson regression in a hierarchical setting. The latter is implemented by using PRIMM (Poisson Regression and Interactive Multilevel Modeling) methods and software (Christiansen & Morris, 1994a). An illustrative example for profiling data is included with k = 11 kidney transplant centers and N = 412 patients.

Graft Survival↗
PubMed1985

Message disruptions during syntactic processing in schizophrenia.

Twenty-four schizophrenics and 24 nonschizophrenic psychiatric patients were given the Hunt test, which requires the subject to use syntactic strategies to synthesize an extended multisentence text on the basis of a controlled set of input propositions. This syntactic processing task induced many more meaning misrepresentations of input propositions in the schizophrenic group compared to the control group. These group differences could not be accounted for by confounding variables such as level of psychopathology, medication, and verbal skills. An error analysis indicated that schizophrenics were highly likely to produce meaning errors when the rewritten proposition assumed a passive syntactic form. Conceptually complex sequences of propositions also resulted in a high frequency of message errors among schizophrenics; this second factor did not account, however, for the high association of errors and passive rewrites. These data are interpreted as indicating that schizophrenics suffer from a multilevel language-production disturbance that includes higher-level message errors that are reflexively induced by lower-level syntactic processing disturbances.

Adolescent↗
PubMed2006

Depression history and coping with chronic pain: a daily process analysis.

This study examined how a previous episode of depression is related to daily pain and reactions to pain among individuals with fibromyalgia, a chronic pain syndrome. Seventy-one women with fibromyalgia (including 30 who were previously depressed) rated their pain and mood 3 times daily for 30 days. Each night, participants rated the extent to which they responded to pain by catastrophizing, how much control they had over that day's pain, their ways of coping with pain that day, and the effectiveness of their coping efforts. Multivariate multilevel regression models revealed that after controlling for neuroticism and current depressive symptoms, formerly depressed and never-depressed individuals differed in how they coped with increased pain and in how they appraised the efficacy of their coping efforts. Formerly depressed participants who also reported more current depressive symptoms showed a greater decline in pleasant mood on more painful days than did formerly depressed participants who were experiencing fewer current depressive symptoms. These findings illustrate how a history of depression can be captured in the dynamics of daily life.

Adaptation, Psychological↗
PubMed2005

Bayesian analysis of hierarchical pattern-mixture models for clinical trials data with attrition and comparisons to commonly used ad-hoc and model-based approaches.

This article addresses the problem of making scientifically sound inferences from clinical trials data with attrition, when reasons of attrition seem related to the outcomes of interest. The problem is particularly difficult when the effect of a covariate is to be estimated and if the dropout mechanism appears to operate differently at different levels of the covariate. In this context, multiple imputation under a multilevel pattern-mixture model that allows random variation across dropout groups is presented. Using simulated data generated around an alcoholic hepatitis trial, we compare the performance of this model and commonly used ad-hoc and model-based approaches.

Algorithms↗