On lumbar disc herniation : aspects of outcome after surgical treatment

Knowledge about sciatica has grown immensely since the days of Hippocrates. Even so one must be impressed with the anatomical insights of those ancient times. Today we are able to describe at a molecular level how the intervertebral disc degenerates and how a herniation is evolved and its physical consequences for the patient. It is now possible, at least partially, to follow the impact a herniation creates on the compressed nerve root, the course of the pain impulses through all modifying systems, up to the brain – and yet not understand the reaction it may cause in that patient! There are still many, many knowledge gaps that need to be filled! Study I: Outcome after surgery for children and adolescents was studied in the Swedish national spine register, Swespine, compared to adults 19-39 and older than 40 years. Children and adolescents were more satisfied with the surgical treatment than adult groups and there was a slight deterioration of outcome by age. Study II: Patients admitted to hospital and surgery non-electively, via the emergency ward, were compared to electively operated patients. At baseline the non-elective group, reported more pain, dysfunction and poorer quality of life, but after surgery all outcome values were almost equal, adjusted or not. Study III: Inflammation around the nerve root is an important factor in the pain elicited by disc herniation. The level of inflammation measured in serum with C-reactive protein before surgery was however not associated with outcome in a prospective study of 177 patients. On the other hand, ‘Plasminogen Activator Inhibitor 1’ (PAI-1), an important factor in fibrinolysis and scar modulation, was to some extent associated to poor outcome in the same cohort of patients. The exact reason for this association is not clear. It may be hypothesized that hypofibrinolysis is associated with excessive scar formation. Study IV: This thesis has used data from Swespine. The validity of these data may be questioned, as a fairly large proportion of patients are lost to follow-up. In an attempt to define if the loss to follow-up has an impact on the interpretation of data from Swespine, a comparison was made with a single-center study with very few patients lost to follow-up. There were some minor baseline differences between the groups, but outcome at 1 and 2 years, was almost equal in all used variables. These data indicate that non-responders in Swespine may be considered lost at random and would not influence the interpretation of data from Swespine

Eco-Hydrology Modeling in Coastal Louisiana to Assess Project Effects on the Landscape

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

An observational study on the outcome after surgery for lumbar disc herniation in adolescents compared to adults based on the Swedish Spine Register

BACKGROUND CONTEXT: Disc-related sciatica has a prevalence of about 2% in adults, but is rare in adolescents. If conservative treatment is unsuccessful, surgery is an option. PURPOSE: The aim of this study was to compare the outcomes of surgery for lumbar disc herniation in adolescents with adults in the Swedish Spine Register. STUDY DESIGN/SETTING: This is a prospective observational study: National Quality Register. PATIENT SAMPLE: This study included 151 patients, 18 years or younger, 4,386 patients, 19-39 years, and 6,078 patients, 40 years or older, followed for 1-2 years after surgery. OUTCOME MEASURES: The primary outcomes were patient satisfaction and global assessment of leg and back pain. Secondary outcomes were Visual Analog Scale ( VAS) leg pain, VAS back pain, Oswestry disability index (ODI), and EuroQol-5 dimensions (EQ-5D). METHODS: Statistical analyses were performed with the Welch F test, the chi-square test, and the Wilcoxon signed-rank test. RESULTS: At follow-up, 86% of the adolescents were satisfied compared with 78% in the younger adults and 76% in the older adults group (p < .001). According to the global assessment, significantly decreased leg pain was experienced by 87% of the adolescents, 78% of the younger adults, and 71% of the older adults (p < .001). Corresponding figures for back pain were 88%, 73%, and 70%, respectively (p < .001). All groups experienced significant postoperative improvement of VAS leg pain, VAS back pain, ODI, and EQ-5D (all p < .001). CONCLUSIONS: The adolescent age group was more satisfied with the treatment than the adult groups. There was a significant improvement in all age groups after surgery.Financial support has been received from the Swedish Society of Spine Surgeons.Accepte

ROC curves in cost space

The final publication is available at Springer via http://dx.doi.org/10.1007/s10994-013-5328-9ROC curves and cost curves are two popular ways of visualising classifier performance, finding appropriate thresholds according to the operating condition, and deriving useful aggregated measures such as the area under the ROC curve (AUC) or the area under the optimal cost curve. In this paper we present new findings and connections between ROC space and cost space. In particular, we show that ROC curves can be transferred to cost space by means of a very natural threshold choice method, which sets the decision threshold such that the proportion of positive predictions equals the operating condition. We call these new curves rate-driven curves, and we demonstrate that the expected loss as measured by the area under these curves is linearly related to AUC. We show that the rate-driven curves are the genuine equivalent of ROC curves in cost space, establishing a point-point rather than a point-line correspondence. Furthermore, a decomposition of the rate-driven curves is introduced which separates the loss due to the threshold choice method from the ranking loss (Kendall τ distance). We also derive the corresponding curve to the ROC convex hull in cost space; this curve is different from the lower envelope of the cost lines, as the latter assumes only optimal thresholds are chosen.We would like to thank the anonymous referees for their helpful comments. This work was supported by the MEC/MINECO projects CONSOLIDER-INGENIO CSD2007-00022 and TIN 2010-21062-C02-02, GVA project PROMETEO/2008/051, the COST-European Cooperation in the field of Scientific and Technical Research IC0801 AT, and the REFRAME project granted by the European Coordinated Research on Long-term Challenges in Information and Communication Sciences & Technologies ERA-Net (CHIST-ERA), and funded by the Engineering and Physical Sciences Research Council in the UK and the Ministerio de Economia y Competitividad in Spain.Hernández Orallo, J.; Flach ., P.; Ferri Ramírez, C. (2013). ROC curves in cost space. Machine Learning. 93(1):71-91. https://doi.org/10.1007/s10994-013-5328-9S7191931Adams, N., & Hand, D. (1999). Comparing classifiers when the misallocation costs are uncertain. Pattern Recognition, 32(7), 1139–1147.Chang, J., & Yap, C. (1986). A polynomial solution for the potato-peeling problem. Discrete & Computational Geometry, 1(1), 155–182.Drummond, C., & Holte, R. (2000). Explicitly representing expected cost: an alternative to ROC representation. In Knowl. discovery & data mining (pp. 198–207).Drummond, C., & Holte, R. (2006). Cost curves: an improved method for visualizing classifier performance. Machine Learning, 65, 95–130.Elkan, C. (2001). The foundations of cost-sensitive learning. In B. Nebel (Ed.), Proc. of the 17th intl. conf. on artificial intelligence (IJCAI-01) (pp. 973–978).Fawcett, T. (2006). An introduction to ROC analysis. Pattern Recognition Letters, 27(8), 861–874.Fawcett, T., & Niculescu-Mizil, A. (2007). PAV and the ROC convex hull. Machine Learning, 68(1), 97–106.Flach, P. (2003). The geometry of ROC space: understanding machine learning metrics through ROC isometrics. In Machine learning, proceedings of the twentieth international conference (ICML 2003) (pp. 194–201).Flach, P., Hernández-Orallo, J., & Ferri, C. (2011). A coherent interpretation of AUC as a measure of aggregated classification performance. In Proc. of the 28th intl. conference on machine learning, ICML2011.Frank, A., & Asuncion, A. (2010). UCI machine learning repository. http://archive.ics.uci.edu/ml .Hand, D. (2009). Measuring classifier performance: a coherent alternative to the area under the ROC curve. Machine Learning, 77(1), 103–123.Hernández-Orallo, J., Flach, P., & Ferri, C. (2011). Brier curves: a new cost-based visualisation of classifier performance. In Proceedings of the 28th international conference on machine learning, ICML2011.Hernández-Orallo, J., Flach, P., & Ferri, C. (2012). A unified view of performance metrics: translating threshold choice into expected classification loss. Journal of Machine Learning Research, 13, 2813–2869.Kendall, M. G. (1938). A new measure of rank correlation. Biometrika, 30(1/2), 81–93. doi: 10.2307/2332226 .Swets, J., Dawes, R., & Monahan, J. (2000). Better decisions through science. Scientific American, 283(4), 82–87

MLSys: The New Frontier of Machine Learning Systems

Machine learning (ML) techniques are enjoying rapidly increasing adoption. However, designing and implementing the systems that support ML models in real-world deployments remains a significant obstacle, in large part due to the radically different development and deployment profile of modern ML methods, and the range of practical concerns that come with broader adoption. We propose to foster a new systems machine learning research community at the intersection of the traditional systems and ML communities, focused on topics such as hardware systems for ML, software systems for ML, and ML optimized for metrics beyond predictive accuracy. To do this, we describe a new conference, MLSys, that explicitly targets research at the intersection of systems and machine learning with a program committee split evenly between experts in systems and ML, and an explicit focus on topics at the intersection of the two

A comparison of specialist rehabilitation and care assistant support with specialist rehabilitation alone and usual care for people with Parkinson's living in the community: study protocol for a randomised controlled trial

<p>Abstract</p> <p>Background</p> <p>Parkinson's Disease is a degenerative neurological condition that causes movement problems and other distressing symptoms. People with Parkinson's disease gradually lose their independence and strain is placed on family members. A multidisciplinary approach to rehabilitation for people with Parkinson's is recommended but has not been widely researched. Studies are needed that investigate cost-effective community-based service delivery models to reduce disability and dependency and admission to long term care, and improve quality of life.</p> <p>Methods</p> <p>A pragmatic three parallel group randomised controlled trial involving people with Parkinson's Disease and live-in carers (family friends or paid carers), and comparing: management by a specialist multidisciplinary team for six weeks, according to a care plan agreed between the professionals and the patient and carer (Group A); multidisciplinary team management and additional support for four months from a trained care assistant (Group B); usual care, no coordinated team care planning or ongoing support (Group C). Follow up will be for six months to determine the impact and relative cost-effectiveness of the two interventions, compared to usual care. The primary outcomes are disability (patients) and strain (carers). Secondary outcomes include patient mobility, falls, speech, pain, self efficacy, health and social care use; carer general health; patient and carer social functioning, psychological wellbeing, health related quality of life. Semi structured interviews will be undertaken with providers (team members, care assistants), service commissioners, and patients and carers in groups A and B, to gain feedback about the acceptability of the interventions. A cost - effectiveness evaluation is embedded in the trial.</p> <p>Discussion</p> <p>The trial investigates components of recent national policy recommendations for people with long term conditions, and Parkinson's Disease in particular, and will provide guidance to inform local service planning and commissioning.</p> <p>Trial registration</p> <p>ISRCTN: <a href="http://www.controlled-trials.com/ISRCTN44577970">ISRCTN44577970</a></p

[Einladungsschreiben an Pius IX. zur 600-Jahr-Feier der Gründung des Kölner Doms]

[EINLADUNGSSCHREIBEN AN PIUS IX. ZUR 600-JAHR-FEIER DER GRÜNDUNG DES KÖLNER DOMS] [Einladungsschreiben an Pius IX. zur 600-Jahr-Feier der Gründung des Kölner Doms] ( - ) Einband ( - ) Heiligster Vater! ([1]) Lithographie "Pio IX" ([2]) Lithographie ([3]) Text ([4]) S. Matthävs ([8]) S. Jacob ([9]