Advancing the science of spatial neglect rehabilitation: an improved statistical approach with mixed linear modeling
Valid research on neglect rehabilitation demands a statistical approach commensurate with the characteristics of neglect rehabilitation data: Neglect arises from impairment in distinct brain networks leading to large between-subject variability in baseline symptoms and recovery trajectories. Studie...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2013-05-01
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| Series: | Frontiers in Human Neuroscience |
| Subjects: | |
| Online Access: | http://journal.frontiersin.org/Journal/10.3389/fnhum.2013.00211/full |
| _version_ | 1819085173167226880 |
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| author | Kelly M Goedert Ray eBoston A M Barrett |
| author_facet | Kelly M Goedert Ray eBoston A M Barrett |
| author_sort | Kelly M Goedert |
| collection | DOAJ |
| description | Valid research on neglect rehabilitation demands a statistical approach commensurate with the characteristics of neglect rehabilitation data: Neglect arises from impairment in distinct brain networks leading to large between-subject variability in baseline symptoms and recovery trajectories. Studies enrolling medically-ill, disabled patients, may suffer from missing, unbalanced data, and small sample sizes. Finally, assessment of rehabilitation requires a description of continuous recovery trajectories. Unfortunately, the statistical method currently employed in most studies of neglect treatment (repeated-measures ANOVA) does not well-address these issues. Here we review an alternative, mixed linear modeling (MLM), that is more appropriate for assessing change over time. MLM better accounts for between-subject heterogeneity in baseline neglect severity and in recovery trajectory. MLM does not require complete or balanced data, nor does it make strict assumptions regarding the data structure. Furthermore, because MLM better models between-subject heterogeneity it often results in increased power to observe treatment effects with smaller samples. After reviewing current practices in the field, and the assumptions of repeated-measures ANOVA, we provide an introduction to MLM. We review its assumptions, uses, advantages and disadvantages. Using real and simulated data, we illustrate how MLM may improve the ability to detect effects of treatment over ANOVA, particularly with the small samples typical of neglect research. Furthermore, our simulation analyses result in recommendations for the design of future rehabilitation studies. Because between-subject heterogeneity is one important reason why studies of neglect treatments often yield conflicting results, employing statistical procedures that model this heterogeneity more accurately will increase the efficiency of our efforts to find treatments to improve the lives of individuals with neglect. |
| first_indexed | 2024-12-21T21:00:08Z |
| format | Article |
| id | doaj.art-418cd374051e4e69bbc3135ed1954eff |
| institution | Directory Open Access Journal |
| issn | 1662-5161 |
| language | English |
| last_indexed | 2024-12-21T21:00:08Z |
| publishDate | 2013-05-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Human Neuroscience |
| spelling | doaj.art-418cd374051e4e69bbc3135ed1954eff2022-12-21T18:50:28ZengFrontiers Media S.A.Frontiers in Human Neuroscience1662-51612013-05-01710.3389/fnhum.2013.0021148435Advancing the science of spatial neglect rehabilitation: an improved statistical approach with mixed linear modelingKelly M Goedert0Ray eBoston1A M Barrett2Seton Hall UniversityUniversity of PennsylvaniaKessler Foundation Research CenterValid research on neglect rehabilitation demands a statistical approach commensurate with the characteristics of neglect rehabilitation data: Neglect arises from impairment in distinct brain networks leading to large between-subject variability in baseline symptoms and recovery trajectories. Studies enrolling medically-ill, disabled patients, may suffer from missing, unbalanced data, and small sample sizes. Finally, assessment of rehabilitation requires a description of continuous recovery trajectories. Unfortunately, the statistical method currently employed in most studies of neglect treatment (repeated-measures ANOVA) does not well-address these issues. Here we review an alternative, mixed linear modeling (MLM), that is more appropriate for assessing change over time. MLM better accounts for between-subject heterogeneity in baseline neglect severity and in recovery trajectory. MLM does not require complete or balanced data, nor does it make strict assumptions regarding the data structure. Furthermore, because MLM better models between-subject heterogeneity it often results in increased power to observe treatment effects with smaller samples. After reviewing current practices in the field, and the assumptions of repeated-measures ANOVA, we provide an introduction to MLM. We review its assumptions, uses, advantages and disadvantages. Using real and simulated data, we illustrate how MLM may improve the ability to detect effects of treatment over ANOVA, particularly with the small samples typical of neglect research. Furthermore, our simulation analyses result in recommendations for the design of future rehabilitation studies. Because between-subject heterogeneity is one important reason why studies of neglect treatments often yield conflicting results, employing statistical procedures that model this heterogeneity more accurately will increase the efficiency of our efforts to find treatments to improve the lives of individuals with neglect.http://journal.frontiersin.org/Journal/10.3389/fnhum.2013.00211/fullRehabilitationSpatial neglectstatistical methodsmixed linear modelingpower simulationType I error simulation |
| spellingShingle | Kelly M Goedert Ray eBoston A M Barrett Advancing the science of spatial neglect rehabilitation: an improved statistical approach with mixed linear modeling Frontiers in Human Neuroscience Rehabilitation Spatial neglect statistical methods mixed linear modeling power simulation Type I error simulation |
| title | Advancing the science of spatial neglect rehabilitation: an improved statistical approach with mixed linear modeling |
| title_full | Advancing the science of spatial neglect rehabilitation: an improved statistical approach with mixed linear modeling |
| title_fullStr | Advancing the science of spatial neglect rehabilitation: an improved statistical approach with mixed linear modeling |
| title_full_unstemmed | Advancing the science of spatial neglect rehabilitation: an improved statistical approach with mixed linear modeling |
| title_short | Advancing the science of spatial neglect rehabilitation: an improved statistical approach with mixed linear modeling |
| title_sort | advancing the science of spatial neglect rehabilitation an improved statistical approach with mixed linear modeling |
| topic | Rehabilitation Spatial neglect statistical methods mixed linear modeling power simulation Type I error simulation |
| url | http://journal.frontiersin.org/Journal/10.3389/fnhum.2013.00211/full |
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