1,720,995 research outputs found
Graphical sensitivity analysis with different methods of imputation for a trial with probable non-ignorable missing data
No full textGraphical sensitivity analyses have recently been recommended for clinical trials with non-ignorable missing binary outcome. We demonstrate an adaptation of this methodology for a continuous outcome of a trial of three cognitive-behavioural therapies for mild depression in primary care, in which one arm had unexpectedly high levels of missing data. Fixed value and multiple imputation from a normal distribution (assuming either varying mean and fixed SD, or fixed mean and varying SD) were used to obtain contour plots of the contrast estimates with their P values superimposed; their confidence interval; and the root mean square error. Imputation was based on both the outcome value alone, or on change from baseline. The plots showed fixed value imputation to be more sensitive than imputing from a normal distribution, but the normally distributed imputations were subject to sampling noise. The contours of the sensitivity plots were close to linear in appearance with the slope approximately equal to the ratio of the proportions of subjects with missing data in each trial arm
The influence of attention deficits on functional recovery post stroke during the first 12 months after discharge from hospital
No full textBackground: Attention deficits have been linked to poor recovery after stroke and may predict outcome. We explored the influence of attention on functional recovery post stroke in the first 12 months after discharge from hospital.Methods: People with stroke completed measures of attention, balance, mobility and activities of daily living (ADL) ability at the point of discharge from hospital, and 6 and 12 months later. We used correlational analysis and stepwise linear regression to explore potential predictors of outcome.Results: We recruited 122 men and women, mean age 70 years. At discharge, 56 (51%) had deficits of divided attention, 45 (37%) of sustained attention, 43 (36%) of auditory selective attention and 41 (37%) had visual selective attention deficits. Attention at discharge correlated with mobility, balance and ADL outcomes 12 months later. After controlling for the level of the outcome at discharge, correlations remained significant in only five of the 12 relationships. Stepwise linear regression revealed that the outcome measured at discharge, days until discharge and number of medications were better predictors of outcome: in no case was an attention variable at discharge selected as a predictor of outcome at 12 months.Conclusions: Although attention and function correlated significantly, this correlation was reduced after controlling for functional ability at discharge. Furthermore, side of lesion and the attention variables were not demonstrated as important predictors of outcome 12 months later.<br/
A systematic review of vanadium oral supplements for glycaemic control in type 2 diabetes mellitus
No full textObjective: To assess the effectiveness of oral vanadium supplementation for glycaemic control in type 2 diabetes by conducting a systematic review of the literature. Design and Methods: Eligible studies were identified by searching 14 databases using standardized terms. Experts, study authors and manufacturers were also contacted. Hand-searching was not undertaken. Selection criteria for inclusion in the review were controlled human trials of vanadium vs. placebo in adults with type 2 diabetes of minimum 2 months duration, and a minimum of 10 subjects per arm. Data extraction, assessment of study quality and outcome analysis were undertaken by two independent reviewers. Results: One hundred and fifty one studies were found but none met the inclusion criteria. We proceeded to summarize the state of existing evidence and plan for a future clinical trial by applying revised, less restrictive criteria to our search, for clinical trials of 30150 mg daily oral vanadium supplementation in diabetic humans. Only five were identified. These demonstrated significant treatment-effects, but due to poor study quality, must be interpreted with caution. Treatment with vanadium often results in gastrointestinal side-effects. Conclusion: There is no rigorous evidence that oral vanadium supplementation improves glycaemic control in type 2 diabetes. The routine use of vanadium for this purpose cannot be recommended. A large-scale randomized controlled trial is needed to address this clinical question
Graphical sensitivity analysis with different methods of imputation for a trial with probable non-ignorable missing data
No full textGraphical sensitivity analyses have recently been recommended for clinical trials with non-ignorable missing outcome. We demonstrate an adaptation of this methodology for a continuous outcome of a trial of three cognitive-behavioural therapies for mild depression in primary care, in which one arm had unexpectedly high levels of missing data. Fixed-value and multiple imputations from a normal distribution (assuming either varying mean and fixed standard deviation, or fixed mean and varying standard deviation) were used to obtain contour plots of the contrast estimates with their?P-values superimposed, their confidence intervals, and the root mean square errors. Imputation was based either on the outcome value alone, or on change from baseline. The plots showed fixed-value imputation to be more sensitive than imputing from a normal distribution, but the normally distributed imputations were subject to sampling noise. The contours of the sensitivity plots were close to linear in appearance, with the slope approximately equal to the ratio of the proportions of subjects with missing data in each trial arm
Dowrick et al. found no relationship between the scores on the Depression Attitude Questionnaire and GPs' ability to identify depressed individuals in the surgery
No full textDoes the use of a constraint mitten, to encourage use of the hemiplegic upper limb, improve arm function in adults with sub-acute stroke?
No full textObjective: To evaluate the effect of a constraint mitten, worn on the unaffected upper limb, on the arm and hand function of participants with hemiplegia. To estimate the sample size for a future trial. Design: An A-B-A design. Setting: Inpatient, outpatient and domiciliary setting. Subjects Ten participants with mild to moderate residual upper limb hemiparesis, between 1 and 12 months post stroke. Intervention: Following a two-week baseline period, 10 participants were advised to wear the constraint mitten on the unaffected upper limb for 9 waking hours/day for two weeks to encourage use of the hemiplegic arm. Existing levels of therapy continued during the whole study. Main measures: The primary outcome measure was the Action Research Arm Test. At the end of the intervention phase participants completed a questionnaire. Participants also recorded their daily use of the constraint mitten during the intervention phase. Results: A mean improvement in the Action Research Arm Test score of 4.0 points (95% confidence interval 1.7 to 6.2; P=00.016) was found during the intervention phase after correcting for background recovery. Mean compliance was 6.7 hours/day (74%), 90% of participants were positive about the intervention and would recommend the treatment to other stroke survivors, although 50% were relieved to stop the mitten-wearing phase. Conclusions: The use of a constraint mitten in upper limb stroke rehabilitation may be a useful adjunct to enhance functional recovery with minimal additional resources. The positive findings from this preliminary study warrant a larger randomized controlled trial of 200 participants in total. <br/
The safety and effectiveness of newer antiepileptics: a comparative postmarketing cohort study
No full textClinical trials for the newer antiepileptic drugs (AEDs) have provided inconclusive information to evaluate comparative risk benefit. The authors use data from postmarketing observational cohort studies to compare the failure of treatment with lamotrigine, vigabatrin, and gabapentin in patients with refractory epilepsy. The Drug Safety Research Unit has conducted prescription event monitoring (PEM) studies for lamotrigine, vigabatrin, and gabapentin to monitor their safety when used in primary care. The primary outcome of this study was time to treatment failure in patients who had been prescribed the drug after the start of the PEM study. Patients on gabapentin had reduced time to treatment failure compared to those on the other 2 drugs. The age- and sex-adjusted hazard ratio of failure was 1.53 (95% confidence interval [CI] = 1.38-1.70) for gabapentin compared to lamotrigine and 1.19 (95% CI = 1.10-1.30) for vigabatrin compared to lamotrigine. The observed differences between the 3 study drugs might be confounded by a higher proportion of patients treated with gabapentin having refractory epilepsy, a shorter duration of the gabapentin PEM study, and a lower relative dose of gabapentin (approved at the time of the PEM study). The current study provides information about the routine usage of newer AEDs, which complements evidence from clinical trials regarding the efficacy and safety of these AEDs. Although this study showed differences on times to treatment failure between lamotrigine, vigabatrin, and gabapentin, the results are only useful when considered together with results from other studies seeking to answer the same questions
Membership of the Royal College of General Practitioners and recognition of depression in primary care
No full textTo determine the effect of membership of the Royal College of General Practitioners (RCGP) on recognition of depression, odds ratios, Lowess-smoothed plots, and regression models were produced for recognition rates in a representative sample of 20 818 patient contacts for members and non-members of the RCGP. Membership of the RCGP did not appear to convey greater ability to discriminate between depressed and non-depressed patients, but members were more likely to recognise depression in both depressed and non-depressed individuals
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