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The need for randomised treatment studies in neglect research
1Institute of Work Health and Organisations, University of Nottingham, Nottingham, UK. nadina.lincoln@nottingham.ac.uk
Restorative Neurology and Neuroscience
|November 23, 2006
Summary
This review found poor methodological quality in spatial neglect rehabilitation trials. While some cognitive rehabilitation interventions showed effects on impairment, evidence for disability improvement was lacking, necessitating higher-quality future studies.
Area of Science:
- Neuroscience
- Rehabilitation Medicine
- Clinical Trials Methodology
Background:
- Spatial neglect is a common and disabling consequence of brain injury, particularly stroke.
- Effective rehabilitation strategies are crucial for improving functional outcomes in patients with spatial neglect.
- Current evidence for the effectiveness of spatial neglect rehabilitation requires critical appraisal of trial quality.
Purpose of the Study:
- To systematically review the methodological quality of existing trials evaluating rehabilitation interventions for spatial neglect.
- To determine the overall effectiveness of these interventions based on available evidence.
Main Methods:
- A systematic literature review and meta-analysis of trials published up to 2005.
- Independent assessment of trial methodological quality by two reviewers.
- Analysis of outcomes using standardized mean differences and random effects models.
Main Results:
- 25 trials (12 RCTs, 13 CCTs) were identified; overall methodological quality was poor, with only 4 trials rated as low risk of bias.
- Cognitive rehabilitation showed a small, non-significant immediate effect on disability (SMD 0.26).
- Interventions demonstrated a significant persisting effect on cancellation errors (SMD -0.76) and improved line bisection performance, though based on limited studies.
Conclusions:
- The methodological quality of spatial neglect rehabilitation trials is generally poor.
- Evidence suggests potential effects of cognitive rehabilitation on measures of impairment, but not on disability.
- Future research must prioritize robust methodologies, including bias reduction, adequate statistical power, and valid disability outcome measures.
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