Abstract：
:The return to play (RTP) process may occur during longitudinal studies tracking recovery after concussion. This factor, which is often omitted within statistical designs, could affect the fit and overall interpretation of the statistical model. This article demonstrates the difference in results and interpretation between 2 linear mixed-model designs: (1) a between-group longitudinal (GROUP) analysis and (2) a between-group longitudinal model that used an inflection point to account for changes around the time of RTP (RTP analysis). These analyses were conducted on instrumented balance data collected on 23 concussed athletes and 25 controls over 8 weeks following concussion. Total sway area and the range of mediolateral acceleration were used as outcome measures. No significant findings were found in the GROUP design for either outcome measure. In contrast, the RTP analysis revealed significant effects of time (P = .007) and RTP change (P = .007), and group*time (P = .028) and group*RTP change (P = .022) interactions for total sway area, and effects of group (P = .011), time (P = .010), and RTP change (P = .014), and group*time (P = .013) and group*RTP change interactions (P = .013) for range of mediolateral acceleration. For both outcomes, the RTP model fit the data significantly better on comparison of likelihood ratios (P ≤ .027). These results suggest that allowing for an inflection point in the statistical design may assist understanding of what happens around clinically meaningful time points. The choice of statistical model had a considerable effect on the interpretation of findings, and provokes discussion around the best method for analyzing longitudinal datasets when important clinical time points like RTP exist.
journal_name
Scand J Med Sci Sportsjournal_title
Scandinavian journal of medicine & science in sportsauthors
Parrington L,Fino NF,Fino PC,Murchison CF,Chesnutt JC,King LAdoi
10.1111/sms.13239subject
Has Abstractpub_date
2018-11-01 00:00:00pages
2436-2442issue
11eissn
0905-7188issn
1600-0838journal_volume
28pub_type
杂志文章abstract：:We aimed to investigate markers of oxidative stress and levels of endogenous and dietary antioxidants in 16 elite female soccer players in response to a 90-min game (average intensity 82+/-3% HRpeak). Blood samples were taken before, immediately and 21 h after the game. Plasma-oxidized glutathione, the ratio of reduce...
journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/j.1600-0838.2009.00987.x
更新日期：2010-08-01 00:00:00
abstract：:To determine if in-season changes in heart rate recovery (HRR) are related to aerobic fitness and performance in collegiate rowers. Twenty-two female collegiate rowers completed testing before and after their competitive season. Body fat percentage (BF%) was determined by dual-energy X-ray absorptiometry. Maximal aero...
journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/sms.12934
更新日期：2018-02-01 00:00:00
abstract：:Among young athletes, sudden deaths are predominantly associated with cardiomyopathies, coronary artery abnormalities and myocarditis, but coronary heart disease is a reality already in this group. The absolute risk of sudden death is, however, low and the benefits of routine medical screening are small. If an athlete...
journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章,评审
doi：10.1111/j.1600-0838.1995.tb00045.x
更新日期：1995-10-01 00:00:00
abstract：:The purpose of this study was to (a) assess the feasibility of recruitment/retention of participants, protocol/resource management, and participant safety, and (b) estimate the size of the effect between the experimental and control groups. This was a feasibility study conducted as a prospective pilot double-blind ran...
journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章,随机对照试验
doi：10.1111/sms.12827
更新日期：2017-12-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/sms.12572
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/j.1600-0838.1999.tb00256.x
更新日期：1999-12-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/sms.13758
更新日期：2020-10-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章,评审
doi：10.1034/j.1600-0838.2003.02477.x
更新日期：2003-04-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1034/j.1600-0838.2002.10178.x
更新日期：2002-12-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/j.1600-0838.2007.00756.x
更新日期：2009-02-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章,评审
doi：10.1111/j.1600-0838.2004.381.x
更新日期：2004-04-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/sms.13229
更新日期：2018-11-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/j.1600-0838.1998.tb00192.x
更新日期：1998-08-01 00:00:00
abstract：:The measurement of physical fitness (PF) is an important factor from many different perspectives. PF is a determinant of healthy child development as it is related to several health outcomes. However, existing taxonomies of the construct and frequently used fitness assessments vary concerning their theoretical assumpt...
journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/sms.12889
更新日期：2018-01-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 临床试验,杂志文章,随机对照试验
doi：10.1111/j.1600-0838.1999.tb00237.x
更新日期：1999-08-01 00:00:00
abstract：:The effects of cardiopulmonary baroreceptors and muscle mechanoreceptors stimulation on cardiac baroreflex sensitivity (BRS), and heart rate variability (HRV) were evaluated by measuring continuously and non-invasively systolic blood pressure (SBP) and pulse interval (PI) during upright and supine passive cycling. BRS...
journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/j.1600-0838.2009.00902.x
更新日期：2010-06-01 00:00:00
abstract：:This study was guided by the Theory of Planned Behavior (TPB) to assess the predictors of rehabilitation intention and adherence following anterior cruciate ligament (ACL) reconstructive surgery in athletes. Participants (n=87; mean age=28.95±7.7 years) volunteered to participate following their first post-surgery phy...
journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/j.1600-0838.2010.01236.x
更新日期：2012-06-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章,随机对照试验
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journal_title：Scandinavian journal of medicine & science in sports
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章,随机对照试验
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更新日期：2007-02-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/j.1600-0838.2006.00616.x
更新日期：2007-12-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/sms.12981
更新日期：2018-03-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/sms.12812
更新日期：2017-12-01 00:00:00
abstract：:The primary objective of this study was to establish sex- and age-specific physical fitness percentiles for French children. The secondary aim was to assess sex, weight status, and age differences for physical fitness levels in French children. A sample of 31 484 children (16 023 boys, 15 461 girls) aged 6-11 years pa...
journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/sms.13607
更新日期：2020-04-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/sms.13418
更新日期：2019-07-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/sms.12361
更新日期：2015-12-01 00:00:00
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journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/j.1600-0838.2006.00597.x
更新日期：2007-10-01 00:00:00
abstract：:Entheses are regions of high-stress concentration that are commonly affected by overuse injuries in sport. This review summarizes current knowledge of their structure-function relationships - at the macroscopic, microscopic and molecular levels. Consideration is given to how stress concentration is reduced at fibrocar...
journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章,评审
doi：10.1111/j.1600-0838.2007.00689.x
更新日期：2007-08-01 00:00:00
abstract：:Laboratory methods that are required to calculate highly precise jump heights during experimental research have never been sufficiently compared and examined. Our first aim was to compare jumping outcome measures of the same jump, using four different methods (double integration from force plate data, rigid-body model...
journal_title：Scandinavian journal of medicine & science in sports
pub_type： 杂志文章
doi：10.1111/sms.13556
更新日期：2020-01-01 00:00:00
