Age-based medical screening of drivers in Switzerland: an ecological study comparing accident rates with Austria and Germany.

BACKGROUND: In Switzerland, as in various other countries throughout the world, elderly drivers have to pass a medical screening assessment every two years to keep their driver's licence. The scientific literature shows no clear evidence that these policies improve road safety. This study evaluated the effects of the Swiss screening policy by comparing the accident and injury rates of elderly road users in Switzerland with those in Austria and Germany, two neighbouring countries without systematic age-based screening policies. The aims of this study were to examine if the screening policy is associated with a reduced risk of elderly car drivers causing serious accidents (research question 1) or with an increased risk of elderly pedestrians or (e-)cyclists being seriously or fatally injured (research question 2). METHODS: In all three countries, data on accidents were taken from official statistics based on police reports and mileage data from national mobility surveys. An accident was defined as serious if at least one person is seriously or fatally injured in it. Accident and injury rates were calculated using distances driven and population size as measurement of exposure. Multiple Poisson regression models were used to examine the association between the Swiss policy and the accident or injury risk of elderly persons. RESULTS: We found no association between the screening policy for elderly drivers in Switzerland and their risk of causing a serious accident (incidence rate ratio [IRR] 1.24, 95% confidence interval [CI] 0.79-1.94). Contrary to other studies, however, the Swiss policy was not associated with an increased risk of elderly pedestrians (IRR 1.16, 95% CI 0.80-1.68) and (e-)cyclists (IRR 0.79, 95% CI 0.56-1.12) being seriously or fatally injured. CONCLUSIONS: The intended positive effect of the Swiss screening policy on accident rates of elderly drivers could not be demonstrated in this study. These findings serve as a basis for discussion on how to proceed with the policy in the future.

Long-term antibiotic treatment for Crohn's disease: systematic review and meta-analysis of placebo-controlled trials.

BACKGROUND: We investigated the effectiveness of long-term antibiotic treatment in patients with Crohn's disease. METHODS: We performed a systematic review and meta-analysis of randomized clinical trials. Data sources were Medline (from 1966 through June 2009), EMBASE (from 1980 through June 2009), Cochrane Central Register of Controlled Trials (issue 3, 2009), and references from relevant publications. Trials that compared antibiotic therapy during at least 3 months with placebo were included. Outcomes were remission in patients with active disease and relapse in patients with inactive disease. Results from intention-to-treat analyses were combined in a random-effects meta-analysis, stratified by class of drug. Odds ratios (ORs) >1 indicate superiority of antibacterial treatment over placebo. Numbers needed to treat for 1 year to keep 1 additional patient in remission were calculated. RESULTS: Sixteen trials that examined 13 treatment regimens in 865 patients were included in the meta-analysis. The median duration of treatment was 6 months (range, 3-24 months). Three trials of nitroimidazoles showed benefit, with a combined OR of 3.54 (95% confidence interval [CI], 1.94-6.47). Similarly, the combined OR from 4 trials of clofazimine was 2.86 (95% CI, 1.67-4.88). For patients with active disease, the number needed to treat was 3.4 (95% CI, 2.3-7.0) for nitroimidazoles and 4.2 (95% CI, 2.7-9.3) for clofazimine. The corresponding numbers needed to treat for inactive disease were 6.1 (95% CI, 5.0-9.7) and 6.9 (95% CI, 5.4-12.0). No benefit was evident for classic drugs against tuberculosis (3 trials; OR, 0.58; 95% CI, 0.29-1.18). Results for clarithromycin were heterogeneous (I(2)=77%; P=.005) and not combined in the meta-analysis. CONCLUSIONS: Long-term treatment with nitroimidazoles or clofazimine appears to be effective in patients with Crohn's disease.

Publication and non-publication of clinical trials: longitudinal study of applications submitted to a research ethics committee.

BACKGROUND: Not all clinical trials are published, which may distort the evidence that is available in the literature. We studied the publication rate of a cohort of clinical trials and identified factors associated with publication and nonpublication of results. METHODS: We analysed the protocols of randomized clinical trials of drug interventions submitted to the research ethics committee of University Hospital (Inselspital) Bern, Switzerland from 1988 to 1998. We identified full articles published up to 2006 by searching the Cochrane CENTRAL database (issue 02/2006) and by contacting investigators. We analyzed factors associated with the publication of trials using descriptive statistics and logistic regression models. RESULTS: 451 study protocols and 375 corresponding articles were analyzed. 233 protocols resulted in at least one publication, a publication rate of 52%. A total of 366 (81%) trials were commercially funded, 47 (10%) had non-commercial funding. 346 trials (77%) were multi-centre studies and 272 of these (79%) were international collaborations. In the adjusted logistic regression model non-commercial funding (Odds Ratio [OR] 2.42, 95% CI 1.14-5.17), multi-centre status (OR 2.09, 95% CI 1.03-4.24), international collaboration (OR 1.87, 95% CI 0.99-3.55) and a sample size above the median of 236 participants (OR 2.04, 95% CI 1.23-3.39) were associated with full publication. CONCLUSIONS: In this cohort of applications to an ethics committee in Switzerland, only about half of clinical drug trials were published. Large multi-centre trials with non-commercial funding were more likely to be published than other trials, but most trials were funded by industry.

Mycobacterium avium subspecies paratuberculosis and Crohn's disease: a systematic review and meta-analysis.

This systematic review assesses the evidence for an association between Mycobacterium avium subspecies paratuberculosis (MAP) and Crohn's disease. We analysed 28 case-control studies comparing MAP in patients with Crohn's disease with individuals free of inflammatory bowel disease (IBD) or patients with ulcerative colitis. Compared with individuals free of IBD, the pooled odds ratio (OR) from studies using PCR in tissue samples was 7.01 (95% CI 3.95-12.4) and was 1.72 (1.02-2.90) in studies using ELISA in serum. ORs were similar for comparisons with ulcerative colitis patients (PCR, 4.13 [1.57-10.9]; ELISA, 1.88 [1.26-2.81]). The association of MAP with Crohn's disease seems to be specific, but its role in the aetiology of Crohn's disease remains to be defined.

Placebo-controlled trials of Chinese herbal medicine and conventional medicine comparative study.

BACKGROUND: Chinese herbal medicine (CHM) is increasingly used in the West, but the evidence on its effectiveness is a matter of debate. We compared the characteristics, study quality and results of clinical trials of CHM and conventional medicine. METHODS: Comparative study of placebo-controlled trials of CHM and conventional medicine. Eleven bibliographic databases and searches by hand of 48 Chinese-language journals. Conventional medicine trials matched for condition and type of outcome were randomly selected from the Cochrane Controlled Trials Register (issue 1, 2003). Trials described as double-blind, with adequate generation of allocation sequence and adequate concealment of allocation, were assumed to be of high quality. Data were analysed using funnel plots and multivariable meta-regression models. RESULTS: 136 CHM trials (119 published in Chinese, 17 published in English) and 136 matched conventional medicine trials (125 published in English) were analysed. The quality of Chinese-language CHM trials tended to be lower than that of English-language CHM trials and conventional medicine trials. Three (2%) CHM trials and 10 (7%) conventional medicine trials were of high quality. In all groups, smaller trials showed more beneficial treatment effects than larger trials. CHM trials published in Chinese showed considerably larger effects than CHM trials published in English (adjusted ratio of ORs 0.29, 95% confidence intervals 0.17-0.52). CONCLUSIONS: Biases are present both in placebo-controlled trials of CHM and conventional medicine, but may be most pronounced in CHM trials published in Chinese-language journals. Only few CHM trials of adequate methodology exist and the effectiveness of CHM therefore remains poorly documented.