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Regina Stegherr Arthur Allignol Reinhard Meister Christof Schaefer Jan Beyersmann 《Statistics in medicine》2020,39(4):481-493
Both delayed study entry (left-truncation) and competing risks are common phenomena in observational time-to-event studies. For example, in studies conducted by Teratology Information Services (TIS) on adverse drug reactions during pregnancy, the natural time scale is gestational age, but women enter the study after time origin and upon contact with the service. Competing risks are present, because an elective termination may be precluded by a spontaneous abortion. If left-truncation is entirely random, the Aalen-Johansen estimator is the canonical estimator of the cumulative incidence functions of the competing events. If the assumption of random left-truncation is in doubt, we propose a new semiparametric estimator of the cumulative incidence function. The dependence between entry time and time-to-event is modeled using a cause-specific Cox proportional hazards model and the marginal (unconditional) estimates are derived via inverse probability weighting arguments. We apply the new estimator to data about coumarin usage during pregnancy. Here, the concern is that the cause-specific hazard of experiencing an induced abortion may depend on the time when seeking advice by a TIS, which also is the time of left-truncation or study entry. While the aims of counseling by a TIS are to reduce the rate of elective terminations based on irrational overestimation of drug risks and to lead to better and safer medical treatment of maternal disease, it is conceivable that women considering an induced abortion are more likely to seek counseling. The new estimator is also evaluated in extensive simulation studies and found preferable compared to the Aalen-Johansen estimator in non–misspecified scenarios and to at least provide for a sensitivity analysis otherwise. 相似文献
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Elfil Mohamed Ahmed Nada Alapati Amritha Bahekar Rucha Kandil Mohamed Kim Christine Schaefer Sara Tinaz Sule Patel Amar S. de Figueiredo John M. Louis Elan D. Koo Brian B. 《Journal of neurology》2020,267(4):966-974
Journal of Neurology - We aimed to determine suicide risk and lifetime suicidal ideation in Parkinson disease (PD) patients versus controls and how depression, demoralization, and insomnia are... 相似文献
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Oluwatobi O Onafowokan Nicola F. Fine Francis Brooks Oliver M. Stokes Timothy WR Briggs Mike Hutton 《European spine journal》2020,29(3):564-578
To examine the strength of evidence available for multiple facet joint injections (FJIs) and medial branch blocks (MBBs), and to report on the variations in the NHS England framework using the getting it right first time (GIRFT) data. Systematic review using patient, intervention, comparison, outcome and study strategy. The literature search using Cochrane, MEDLINE and EMBASE databases using MeSH terms: lumbar spine, spinal injection and facet joint (“Appendix A”). Three studies were identified that investigated the efficacy of multiple FJIs or MBBs. None of these studies reported sustained positive outcomes at long-term follow-up. There is a paucity of levels I and II evidence available for the efficacy of multiple FJIs and MBBs in treating low back pain. GIRFT data show a high degree of variation in the use of multiple FJIs, which would not be supported by the literature. These slides can be retrieved under Electronic Supplementary Material. 相似文献
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Brink Vera van Driel Catheleine el Bouhaddani Saliha Wardenaar Klaas J. van Domburgh Lieke Schaefer Barbara van Beilen Marije Bartels-Velthuis Agna A. Veling Wim 《European child & adolescent psychiatry》2020,29(6):897-900
European Child & Adolescent Psychiatry - In the Original Publication Table 2 was incorrectly published. The correct table is given below. 相似文献
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Stephen Murphy James Smadbeck Bruce Eckloff Yean Lee Sarah Johnson Giannoula Karagouga Vishnu Serla Anurag Sharma Robert Sikkink Jesse Voss Faye Harris Janet Schaefer Kline Farhad Kosari Andrew Feldman Eric Wieben Marie Christine Aubry Benjamin Kipp Jin Jen George Vasmatzis 《The Journal of molecular diagnostics : JMD》2021,23(4):375-388
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Kienbaum Peter Schaefer Maximilian S. Weibel Stephanie Schlesinger Tobias Meybohm Patrick Eberhart Leopold H. Kranke Peter 《Der Anaesthesist》2022,71(2):123-128
Die Anaesthesiologie - Auch wenn für Anästhesiologen über Jahrzehnte die Prophylaxe und Therapie postoperativer Schmerzen im Rahmen des postoperativen Patientenkomforts an vorderster... 相似文献
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Schaefer Jordan K. Barnes Geoffrey D. Sussman Jeremy B. Saini Sameer D. Caverly Tanner J. Read Susan Zikmund-Fisher Brian J. Kurlander Jacob E. 《Journal of thrombosis and thrombolysis》2022,54(4):639-646
Journal of Thrombosis and Thrombolysis - Recent trials suggest that aspirin for primary prevention may do more harm than good for some, including adults over 70 years of age. We sought to... 相似文献