Estimation of data adaptive minimal clinically important difference with a nonconvex optimization procedure

2019 ◽  
Vol 29 (3) ◽  
pp. 879-893 ◽  
Author(s):  
Zehua Zhou ◽  
Jiwei Zhao ◽  
Leslie J. Bisson
Keyword(s):  
Clinical Significance ◽  
Statistical Significance ◽  
A Priori ◽  
Optimization Procedure ◽  
Adaptive Method ◽  
Individual Level ◽  
Gradient Based ◽  
Data Adaptive ◽  
The Individual ◽  
Important Significance

Understanding the limitation of solely relying on statistical significance, researchers have proposed methods to draw biomedical conclusions based on clinical significance. The minimal clinically important significance is one of the most fundamental concepts to study clinical significance. Based on an anchor question usually available in the patients' reported outcome, Hedayat et al. presented a method to estimate minimal clinically important significance using the classification technique. However, their method implicitly requires that the binary outcome of the anchor question is equally likely, i.e. the balanced outcome assumption. This assumption cannot be guaranteed a priori when one designs the study; hence, it cannot be satisfied in general. In this paper, we propose a data adaptive method, which can overcome this limitation. Compared to Hedayat et al., our method uses a faster gradient based algorithm and adopts a more flexible structure of the minimal clinically important significance at the individual level. We conduct comprehensive simulation studies and apply our method to the chondral lesions and meniscus procedure study to demonstrate its usefulness and also its outperformance.

scholarly journals Predicting the duration of sickness absence spells due to back pain: a population-based study from Sweden

2019 ◽  
Vol 77 (2) ◽  
pp. 115-121
Author(s):  
Annina Ropponen ◽  
Katalin Gémes ◽  
Paolo Frumento ◽  
Gino Almondo ◽  
Matteo Bottai ◽  
...  
Keyword(s):  
Back Pain ◽  
Sickness Absence ◽  
A Priori ◽  
Population Based ◽  
Final Model ◽  
Individual Level ◽  
Discriminatory Accuracy ◽  
C Statistic ◽  
International Statistical Classification ◽  
The Individual

ObjectivesWe aimed to develop and validate a prediction model for the duration of sickness absence (SA) spells due to back pain (International Statistical Classification of Diseases and Related Health Problems 10th Revision: M54), using Swedish nationwide register microdata.MethodsInformation on all new SA spells >14 days from 1 January 2010 to 30 June 2012 and on possible predictors were obtained. The duration of SA was predicted by using piecewise constant hazard models. Nine predictors were selected for the final model based on a priori decision and log-likelihood loss. The final model was estimated in a random sample of 70% of the SA spells and later validated in the remaining 30%.ResultsOverall, 64 048 SA spells due to back pain were identified during the 2.5 years; 74% lasted ≤90 days, and 9% >365 days. The predictors included in the final model were age, sex, geographical region, employment status, multimorbidity, SA extent at the start of the spell, initiation of SA spell in primary healthcare and number of SA days and specialised outpatient healthcare visits from the preceding year. The overall c-statistic (0.547, 95% CI 0.542 to 0.552) suggested a low discriminatory capacity at the individual level. The c-statistic was 0.643 (95% CI 0.634 to 0.652) to predict >90 days spells, 0.686 (95% CI 0.676 to 0.697) to predict >180 spells and 0.753 (95% CI 0.740 to 0.766) to predict >365 days spells.ConclusionsThe model discriminates SA spells >365 days from shorter SA spells with good discriminatory accuracy.

scholarly journals Under fire –simultaneous volatilome and transcriptome analysis unravels fine-scale responses of tansy chemotypes to dual herbivore attack

2020 ◽  
Author(s):  
Mary V. Clancy ◽  
Georg Haberer ◽  
Werner Jud ◽  
Bishu Niederbacher ◽  
Simon Niederbacher ◽  
...  
Keyword(s):  
De Novo ◽  
A Priori ◽  
Insect Community ◽  
Aphid Infestation ◽  
Voc Emissions ◽  
Individual Level ◽  
Herbivore Attack ◽  
Pre Treatment ◽  
Insect Interactions ◽  
The Individual

Abstract BackgroundTansy plants (Tanacetum vulgare L.) are known for their high intraspecific chemical variation, especially of volatile organic compounds (VOC) from the terpenoid compound group. These VOCs are closely involved in plant-insect interactions and, when profiled, can be used to classify plants into groups known as chemotypes. Tansy chemotypes have been shown to influence plant-aphid interactions, however, to date no information is available on the response of different tansy chemotypes to simultaneous herbivory by more than one insect species.ResultsUsing a multi-cuvette system, we investigated the responses of five tansy chemotypes to feeding by sucking and/or chewing herbivores (aphids and caterpillars; Metopeurum fuscoviride Stroyan and Spodoptera littoralis Boisduval). Herbivory by caterpillars following aphid infestation led to a plant chemotype-specific change in the patterns of terpenoids stored in trichome hairs and in VOC emissions. The transcriptomic analysis of a plant chemotype represents the first de novo assembly of a transcriptome in tansy and demonstrates priming effects of aphids on a subsequent herbivory. Overall, we show that the five chemotypes do not react in the same way to the two herbivores. As expected, we found that caterpillar feeding increased VOC emissions, however, a priori aphid infestation only led to a further increase in VOC emissions for some chemotypes.ConclusionsWe were able to show that different chemotypes respond to the double herbivore attack in different ways, and that pre-treatment with aphids had a priming effect on plants when they were subsequently exposed to a chewing herbivore. If neighbouring chemotypes in a field population react differently to herbivory/dual herbivory, this could possibly have effects from the individual level to the group level. Individuals of some chemotypes may respond more efficiently to herbivory stress than others, and in a group environment these "louder" chemotypes may affect the local insect community, including the natural enemies of herbivores, and other neighbouring plants.

scholarly journals Role Ambiguity in Sport Teams

2003 ◽  
Vol 25 (4) ◽  
pp. 534-550 ◽  
Author(s):  
Mark A. Eys ◽  
Albert V. Carron ◽  
Mark R. Beauchamp ◽  
Steven R. Bray
Keyword(s):  
Role Ambiguity ◽  
A Priori ◽  
Operational Definition ◽  
General Purpose ◽  
Future Research ◽  
First Year ◽  
Individual Level ◽  
Sport Teams ◽  
Definition Of ◽  
The Individual

The general purpose of the present study was to examine the nature of role ambiguity in sport teams and to explore the construct validity of the operational definition of role ambiguity developed by Beauchamp, Bray, Eys, and Carron (2002). Role ambiguity was operationalized as a multidimensional construct (Scope of Responsibilities, Behavioral Responsibilities, Evaluation of Performance, and Consequences of Not Fulfilling Responsibilities) that occurs in two contexts, offense and defense. Consistent with the a priori hypothesis, perceptions of role ambiguity exhibited some degree of within-group consistency and group-level variability, but most of the variance in role ambiguity was seen at the individual level. Also, perceptions of role ambiguity decreased from early to late season. Finally, veteran athletes experienced less role ambiguity than first-year athletes at the beginning of the season, but not at the end. Implications of the findings and suggestions for future research are discussed.

scholarly journals Under fire–simultaneous volatilome and transcriptome analysis unravels fine-scale responses of tansy chemotypes to dual herbivore attack.

2020 ◽  
Author(s):  
Mary V. Clancy ◽  
Georg Haberer ◽  
Werner Jud ◽  
Bishu Niederbacher ◽  
Simon Niederbacher ◽  
...  
Keyword(s):  
De Novo ◽  
A Priori ◽  
Insect Community ◽  
Aphid Infestation ◽  
Voc Emissions ◽  
Individual Level ◽  
Herbivore Attack ◽  
Pre Treatment ◽  
Insect Interactions ◽  
The Individual

Abstract BackgroundTansy plants (Tanacetum vulgare L.) are known for their high intraspecific chemical variation, especially of volatile organic compounds (VOC) from the terpenoid compound group. These VOCs are closely involved in plant-insect interactions and, when profiled, can be used to classify plants into groups known as chemotypes. Tansy chemotypes have been shown to influence plant-aphid interactions, however, to date no information is available on the response of different tansy chemotypes to simultaneous herbivory by more than one insect species.ResultsUsing a multi-cuvette system, we investigated the responses of five tansy chemotypes to feeding by sucking and/or chewing herbivores (aphids and caterpillars; Metopeurum fuscoviride Stroyan and Spodoptera littoralis Boisduval). Herbivory by caterpillars following aphid infestation led to a plant chemotype-specific change in the patterns of terpenoids stored in trichome hairs and in VOC emissions. The transcriptomic analysis of a plant chemotype represents the first de novo assembly of a transcriptome in tansy and demonstrates priming effects of aphids on a subsequent herbivory. Overall, we show that the five chemotypes do not react in the same way to the two herbivores. As expected, we found that caterpillar feeding increased VOC emissions, however, a priori aphid infestation only led to a further increase in VOC emissions for some chemotypes.ConclusionsWe were able to show that different chemotypes respond to the double herbivore attack in different ways, and that pre-treatment with aphids had a priming effect on plants when they were subsequently exposed to a chewing herbivore. If neighbouring chemotypes in a field population react differently to herbivory/dual herbivory, this could possibly have effects from the individual level to the group level. Individuals of some chemotypes may respond more efficiently to herbivory stress than others, and in a group environment these "louder" chemotypes may affect the local insect community, including the natural enemies of herbivores, and other neighbouring plants.

scholarly journals Ecological Correlates of Preschooler Obesity: A Multilevel Study

2019 ◽  
Vol 11 (13) ◽  
pp. 50
Author(s):  
Yunhee Park
Keyword(s):  
Sedentary Behavior ◽  
Screen Time ◽  
Statistical Significance ◽  
Population Group ◽  
Organizational Level ◽  
Obesity Risk ◽  
Individual Level ◽  
Risk Reduction Intervention ◽  
The Individual ◽  
A Prospective Study

BACKGROUND: The risk factors for preschooler obesity at various levels have been identified, but little is known about the organizational-level factors of environments in which preschoolers spend long periods of time. METHODS: This study focused on factors at the organizational level and attempted multilevel modeling to appropriately estimate the effects with individual-level factors controlled. In 2013 and 2019, data from 295 and 112 preschoolers aged 2–5 years were collected, combined, and analyzed. RESULTS: At the individual level, mother’s sedentary behavior was a significant factor, while at the organizational level, teacher’s sedentary behavior was a significant factor. CONCLUSION: Focus should be placed on developing obesity risk reduction intervention for this population group. Although there no statistical significance was observed, there is a need to improve the organizational environment such as reducing screen time and shortening the duration of study-focused programs. Moreover, further investigation in a prospective study is required to determine the evidence of these proposed interventions.

scholarly journals Under fire-simultaneous volatilome and transcriptome analysis unravels fine-scale responses of tansy chemotypes to dual herbivore attack.

2020 ◽  
Author(s):  
Mary V. Clancy ◽  
Georg Haberer ◽  
Werner Jud ◽  
Bishu Niederbacher ◽  
Simon Niederbacher ◽  
...  
Keyword(s):  
De Novo ◽  
A Priori ◽  
Insect Community ◽  
Aphid Infestation ◽  
Voc Emissions ◽  
Individual Level ◽  
Herbivore Attack ◽  
Pre Treatment ◽  
Insect Interactions ◽  
The Individual

Abstract BackgroundTansy plants (Tanacetum vulgare L.) are known for their high intraspecific chemical variation, especially of volatile organic compounds (VOC) from the terpenoid compound group. These VOCs are closely involved in plant-insect interactions and, when profiled, can be used to classify plants into groups known as chemotypes. Tansy chemotypes have been shown to influence plant-aphid interactions, however, to date no information is available on the response of different tansy chemotypes to simultaneous herbivory by more than one insect species.ResultsUsing a multi-cuvette system, we investigated the responses of five tansy chemotypes to feeding by sucking and/or chewing herbivores (aphids and caterpillars; Metopeurum fuscoviride Stroyan and Spodoptera littoralis Boisduval). Herbivory by caterpillars following aphid infestation led to a plant chemotype-specific change in the patterns of terpenoids stored in trichome hairs and in VOC emissions. The transcriptomic analysis of a plant chemotype represents the first de novo assembly of a transcriptome in tansy and demonstrates priming effects of aphids on a subsequent herbivory. Overall, we show that the five chemotypes do not react in the same way to the two herbivores. As expected, we found that caterpillar feeding increased VOC emissions, however, a priori aphid infestation only led to a further increase in VOC emissions for some chemotypes.ConclusionsWe were able to show that different chemotypes respond to the double herbivore attack in different ways, and that pre-treatment with aphids had a priming effect on plants when they were subsequently exposed to a chewing herbivore. If neighbouring chemotypes in a field population react differently to herbivory/dual herbivory, this could possibly have effects from the individual level to the group level. Individuals of some chemotypes may respond more efficiently to herbivory stress than others, and in a group environment these "louder" chemotypes may affect the local insect community, including the natural enemies of herbivores, and other neighbouring plants.

scholarly journals Effect of different training modes of strength exercises on a student’s body

2020 ◽  
Vol 24 (3) ◽  
pp. 149-153
Author(s):  
Alexander A. Fedyakin ◽  
Zhanna G. Kortava ◽  
Lidia K. Fedyakina ◽  
Natalia Yu. Zaplatina
Keyword(s):  
Heart Rate ◽  
Statistical Significance ◽  
Wilcoxon Test ◽  
Male Students ◽  
Training Effect ◽  
State University ◽  
Static Mode ◽  
Individual Level ◽  
Strength Exercises ◽  
The Individual

Background and Study Aim. Scientific-methodical literature underlined the importance of improving the effectiveness of physical education’s tools and methods during the scheduled university lessons. Scientists point out the necessity to take into account every factor determining the training effect of lessons with strength exercises. The immediate training effect can be determined by measuring the heart rate during different modes of strength exercises and during recovery. The aim of this study is to analyse the strength exercises’ immediate training effect on a student’s body in the static mode and in the isotonic mode. Material and Methods.  In the study participated 47 freshman male students of the Sochi State University (Russia). The study took place in September-December 2019. Heart rate was measured with Sport Testers POLAR RS-400 during strength exercises and during recovery. The results were analysed in the computer programme SPSS Statistics v22.0. Statistical significance of the results was defined using non-parametric Wilcoxon test. Heart rate was analysed during four types of plank positions in static and isotonic modes. Results: The study determined the effect of different training modes of strength exercises on a student’s body. The immediate training effect of doing the bodyweight strength exercises in the isotonic mode compared to the static mode is characterised by a higher maximum heart rate at the end of doing the exercise (р<0,05); a higher average heart rate during the exercise and during rest until the next exercise (р<0,05); a higher combined heart rate (р<0,05). Conclusion: The isotonic mode of the bodyweight strength exercises has a more prominent training effect than the static mode due to the specific nature of muscle contractions. Due to analysed heart rate values, the authors recommend taking into account the individual level of every student’s physical fitness.

scholarly journals Under fire-simultaneous volatilome and transcriptome analysis unravels fine-scale responses of tansy chemotypes to dual herbivore attack

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Mary V. Clancy ◽  
Georg Haberer ◽  
Werner Jud ◽  
Bishu Niederbacher ◽  
Simon Niederbacher ◽  
...  
Keyword(s):  
De Novo ◽  
A Priori ◽  
Insect Community ◽  
Aphid Infestation ◽  
Voc Emissions ◽  
Individual Level ◽  
Herbivore Attack ◽  
Pre Treatment ◽  
Insect Interactions ◽  
The Individual

Abstract Background Tansy plants (Tanacetum vulgare L.) are known for their high intraspecific chemical variation, especially of volatile organic compounds (VOC) from the terpenoid compound group. These VOCs are closely involved in plant-insect interactions and, when profiled, can be used to classify plants into groups known as chemotypes. Tansy chemotypes have been shown to influence plant-aphid interactions, however, to date no information is available on the response of different tansy chemotypes to simultaneous herbivory by more than one insect species. Results Using a multi-cuvette system, we investigated the responses of five tansy chemotypes to feeding by sucking and/or chewing herbivores (aphids and caterpillars; Metopeurum fuscoviride Stroyan and Spodoptera littoralis Boisduval). Herbivory by caterpillars following aphid infestation led to a plant chemotype-specific change in the patterns of terpenoids stored in trichome hairs and in VOC emissions. The transcriptomic analysis of a plant chemotype represents the first de novo assembly of a transcriptome in tansy and demonstrates priming effects of aphids on a subsequent herbivory. Overall, we show that the five chemotypes do not react in the same way to the two herbivores. As expected, we found that caterpillar feeding increased VOC emissions, however, a priori aphid infestation only led to a further increase in VOC emissions for some chemotypes. Conclusions We were able to show that different chemotypes respond to the double herbivore attack in different ways, and that pre-treatment with aphids had a priming effect on plants when they were subsequently exposed to a chewing herbivore. If neighbouring chemotypes in a field population react differently to herbivory/dual herbivory, this could possibly have effects from the individual level to the group level. Individuals of some chemotypes may respond more efficiently to herbivory stress than others, and in a group environment these “louder” chemotypes may affect the local insect community, including the natural enemies of herbivores, and other neighbouring plants.

scholarly journals Mechanism-based Explanations versus Autonomy in the Social Sciences

2018 ◽  
Vol 67 (1) ◽  
pp. 35-50 ◽  
Author(s):  
Ståle Gundersen
Keyword(s):  
Social Sciences ◽  
Social Science ◽  
Psychological Factors ◽  
A Priori ◽  
Individual Level ◽  
The Social ◽  
Explanatory Depth ◽  
Underlying Mechanisms ◽  
The Individual ◽  
Social Level

Mechanism-based explanations are widely discussed in contemporary social science. A virtue of mechanism-based explanations is that they can tell us how social and psychological factors are related to each other and in addition provide explanatory depth. I will argue against an argument which contends that to describe underlying mechanisms at the individual level do not contribute to improve macro-explanations at the social level. However, the critics of the mechanism approach are right that under certain conditions there can be successful explanations without mentioning underlying mechanisms. Although the mechanism approach is a reductive strategy, it does not entail that the social sciences will lose their descriptively and explanatory autonomy. The debate about reductionism and explanation often take place at an abstract philosophical level, but it is argued that to what extent the mechanism approach will influence the autonomy of the social sciences is an empirical problem and cannot be decided a priori.

scholarly journals Effect of a System-Oriented Intervention on Compliance Problems in Schizophrenia: A Pragmatic Controlled Trial

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Hanne Skarsholm ◽  
Henrik Stoevring ◽  
Bent Nielsen
Keyword(s):  
Missing Values ◽  
Reference Group ◽  
Controlled Trial ◽  
Statistical Significance ◽  
System Level ◽  
Multifactorial Intervention ◽  
Attrition Rates ◽  
Individual Level ◽  
Significant Difference ◽  
The Individual

Background. Numerous studies have been conducted with a view to developing strategies for improvement of medical compliance in patients with schizophrenia. All of the studies conducted so far have had an individual approach to compliance based on the assumption that noncompliance is determined individually due to inappropriate behavior in the patient. We conducted a pragmatic controlled trial with a system-oriented approach, to provide a new perspective on compliance and test the efficacy of a multifactorial intervention at the system level in a routine clinical setting, an approach that has not previously been used for the improvement of compliance.Methods. 30 patients were allocated to the system-oriented therapy and 40 patients were allocated to the reference intervention, which consisted of individually based compliance therapy. The follow-up period was six months. Primary endpoint was improvement in compliance, measured by improvement in a compliance scale specifically developed for the project.Results. When accounting for missing values with a multiple imputation approach, we found a tendency toward a difference in both the compliance scale and PANSS favoring the system-oriented therapy, although it did not reach statistical significance. A significant difference in incidence of adverse events and time to first readmission was found. Attrition rates were significantly higher in the reference group and nonsignificant among individuals with lower compliance, which may have diluted effect estimates. This was reflected by significant differences found in an analysis based on a last observation carried forward approach.Conclusion. This study suggests that compliance problems are better solved by a multifactorial intervention at the system level than at the individual level.

Sign in / Sign up

Export Citation Format

Share Document