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  • 1
    Online Resource
    Online Resource
    The net effect of alternative allocation ratios on recruitment time and trial cost
    SAGE Publications ; 2009
    In:  Clinical Trials Vol. 6, No. 2 ( 2009-04), p. 126-132
    Details
    In: Clinical Trials, SAGE Publications, Vol. 6, No. 2 ( 2009-04), p. 126-132
    Abstract: Background Increasing the proportion of subjects allocated to the experimental treatment in controlled clinical trials is often advocated as a method of increasing recruitment rates and improving the performance of trials. The presumption is that the higher likelihood of randomization to the experimental treatment will be perceived by potential study enrollees as an added benefit of participation and will increase recruitment rates and speed the completion of trials. However, studies with alternative allocation ratios require a larger sample size to maintain statistical power, which may result in a net increase in time required to complete recruitment and a net increase in total trial cost. Purpose To describe the potential net effect of alternative allocation ratios on recruitment time and trial cost. Methods Models of recruitment time and trial cost were developed and used to compare trials with 1:1 allocation to trials with alternative allocation ratios under a range of per subject costs, per day costs, and enrollment rates. Results In regard to time required to complete recruitment, alternative allocation ratios are net beneficial if the recruitment rate improves by more than about 4% for trials with a 1.5:1 allocation ratio and 12% for trials with a 2:1 allocation ratio. More substantial improvements in recruitment rate, 13 and 47% respectively for scenarios we considered, are required for alternative allocation to be net beneficial in terms of tangible monetary cost. Limitations The cost models were developed expressly for trials comparing proportions or means across treatment groups. Conclusions Using alternative allocation ratio designs to improve recruitment may or may not be time and cost-effective. Using alternative allocation for this purpose should only be considered for trial contexts where there is both clear evidence that the alternative design does improve recruitment rates and the attained time or cost efficiency justifies the added study subject burden implied by a larger sample size. Clinical Trials 2009; 6: 126—132. http://ctj.sagepub.com
    Type of Medium: Online Resource
    ISSN: 1740-7745 , 1740-7753
    URL: Article
    DOI: 10.1177/1740774509103485
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2009
    detail.hit.zdb_id: 2159773-X
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  • 2
    Online Resource
    Online Resource
    Assessing the Motor Status Score: A Scale for the Evaluation of Upper Limb Motor Outcomes in Patients after Stroke
    SAGE Publications ; 2002
    In:  Neurorehabilitation and Neural Repair Vol. 16, No. 3 ( 2002-09), p. 283-289
    Details
    In: Neurorehabilitation and Neural Repair, SAGE Publications, Vol. 16, No. 3 ( 2002-09), p. 283-289
    Abstract: The Motor Status Scale (MSS) measures shoulder, elbow (maximum score = 40), wrist, hand, and finger movements (maximum score = 42), and expands the measurement of upper extremity impairment and disability provided by the Fugl-Meyer (FM) score. This work examines the interrater reliability and criterion validity of the MSS performed in patients admitted to a rehabilitation hospital 21 ± 4 days after stroke. Using the MSS and the FM, 7 occupational therapists masked to each other’s judgments, evaluated 12 consecutive patients with stroke. Two therapists evaluated 6 additional patients on consecutive days. Intraclass correlation coefficients were significant for each group of raters for the shoulder/elbow and for the wrist/hand (P 〈 0.0001); test-retest measures were also significant for the shoulder/elbow (Pearson correlation coefficient r = 0.99, P 〈 0.004) and for the wrist/hand (Pearson correlation coefficient r = 0.99, P 〈 0.003). The internal item consistency for the overall MSS was significant (Cronbach alpha = 0.98, P 〈 0.0001). Finally the correlation between the MSS and the FM (R 2 = 0.964) was significant (P 〈 0.0001). The MSS affords a reliable and valid assessment of upper limb impairment and disability following stroke.
    Type of Medium: Online Resource
    ISSN: 1545-9683 , 1552-6844
    URL: Article
    DOI: 10.1177/154596830201600306
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2002
    detail.hit.zdb_id: 2100545-X
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  • 3
    Online Resource
    Online Resource
    One-trial 10-item free-recall performance in Taiwanese elderly and near-elderly: A potential screen for cognitive decline
    SAGE Publications ; 2005
    In:  American Journal of Alzheimer's Disease & Other Dementiasr Vol. 20, No. 4 ( 2005-07), p. 239-247
    Details
    In: American Journal of Alzheimer's Disease & Other Dementiasr, SAGE Publications, Vol. 20, No. 4 ( 2005-07), p. 239-247
    Abstract: To explore a one-trial 10-item free-recall test as a potential dementia screening tool, we analyzed recall scores and individualized serial position effects in nearelderly (N = 2,336) and elderly (N = 2,371) participants in a population-based survey in Taiwan. Age and sex were significantly associated with recall score [younger 〉 older (p 〈 0.001); men 〉 women (p 〈 0.001)]; after controlling for gender and age group, weak association between recall and education was still observed. By contrast, serial position effects (SPEs), defined for each participant and analyzed aggregated over each age group, were not associated with education and tended not to be associated with sex. Primacy effects were observed in 67 to 80 percent, and recency effects were observed in 41 to 54 percent of respondents. Because SPEs were defined for each respondent, we could determine that loss of the primacy effect was associated with significantly larger losses in total recall score in elderly persons who had exhibited both SPEs at the first survey, as compared to those who maintained both SPEs at successive surveys (p 〈 0.01). Elderly subjects showed slight longitudinal decline in free recall. A one-trial 10-item free-recall test demonstrated age-related cognitive decline in this Taiwanese population survey cohort; SPEs at the individual level may be useful markers for important cognitive change and warrant further study and benchmarking against valid and reliable tests of memory and cognitive decline.
    Type of Medium: Online Resource
    ISSN: 1533-3175 , 1938-2731
    URL: Article
    DOI: 10.1177/153331750502000410
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2005
    detail.hit.zdb_id: 2235173-5
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  • 4
    Online Resource
    Online Resource
    Neuropsychiatric Symptoms and Regional Neocortical Atrophy in Mild Cognitive Impairment and Alzheimer’s Disease
    SAGE Publications ; 2014
    In:  American Journal of Alzheimer's Disease & Other Dementiasr Vol. 29, No. 2 ( 2014-03), p. 159-165
    Details
    In: American Journal of Alzheimer's Disease & Other Dementiasr, SAGE Publications, Vol. 29, No. 2 ( 2014-03), p. 159-165
    Abstract: To assess the relationship between regional neocortical atrophy and psychotic symptoms in adults with mild cognitive impairment (MCI) and Alzheimer’s disease (AD). Methods: Rates of change in regional neocortical atrophy as measured by longitudinal magnetic resonance imaging scans and the occurrence of psychotic symptoms and/or the long-term use of antipsychotic medications in 389 outpatients with MCI or AD in Alzheimer’s Disease Neuroimaging Initiative. Results: Atrophy rate of 3 specific neocortical regions, lateral frontal, lateral parietal, and anterior cingulate gyrus, was significantly associated with the onset of psychosis including delusions, agitation, wandering, and hallucinations and/or the need for chronic antipsychotic medications. Atrophy rate of the lateral frontal lobe correlated most significantly with onset of psychotic symptoms or need for chronic antipsychotic medications. Conclusions: Psychosis was associated with volume loss in specific regions of the lateral frontal and parietal lobes as well as anterior cingulate gyrus.
    Type of Medium: Online Resource
    ISSN: 1533-3175 , 1938-2731
    URL: Article
    DOI: 10.1177/1533317513507373
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2014
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