Understanding urban accessibility: A community-engaged pilot study of entrance features.

The accessibility of the built environment is an equity issue. Accessibility standards for buildings exist, but often apply to new buildings or major renovations. This renders historic neighborhoods inaccessible.

Correction to: Sample size estimation for randomised controlled trials with repeated assessment of patient-reported outcomes: what correlation between baseline and follow-up outcomes should we assume?

Following publication of the original article [1], we have been notified that one of an error in the Conclusions section of the Abstract.

Sample size estimation for randomised controlled trials with repeated assessment of patient-reported outcomes: what correlation between baseline and follow-up outcomes should we assume?

Background: Patient-reported outcome measures (PROMs) are now frequently used in randomised controlled trials (RCTs) as primary endpoints. RCTs are longitudinal, and many have a baseline (PRE) assessment of the outcome and one or more post-randomisation assessments of outcome (POST). With such pre-test post-test RCT designs there are several ways of estimating the sample size and analysing the outcome data: analysis of post-randomisation treatment means (POST); analysis of mean changes from pre- to post-randomisation (CHANGE); analysis of covariance (ANCOVA).

Statistical design and analysis in trials of proportionate interventions: a systematic review.

Background: In proportionate or adaptive interventions, the dose or intensity can be adjusted based on individual need at predefined decision stages during the delivery of the intervention. The development of such interventions may require an evaluation of the effectiveness of the individual stages in addition to the whole intervention. However, evaluating individual stages of an intervention has various challenges, particularly the statistical design and analysis.

Appropriate statistical methods for analysing partially nested randomised controlled trials with continuous outcomes: a simulation study.

Background: In individually randomised trials we might expect interventions delivered in groups or by care providers to result in clustering of outcomes for participants treated in the same group or by the same care provider. In partially nested randomised controlled trials (pnRCTs) this clustering only occurs in one trial arm, commonly the intervention arm. It is important to measure and account for between-cluster variability in trial design and analysis.

What is an ROC curve?

The paper by Body is concerned with the evaluation of decision aids, which can be used to identify potential acute coronary syndromes (ACS) in the ED. The authors previously developed the Manchester Acute Coronary Syndromes model (MACS) decision aid, which uses several clinical variables and two biomarkers to 'rule in' and 'rule out' ACS. However, one of the two biomarkers (heart-type fatty acid bindingprotein, H-FABP) is not widely used so a revised decision aid has been developed (Troponin-only Manchester Acute Coronary Syndromes, T-MACS), which include a single biomarker hs-cTnT.

Evaluation of biases present in the cohort multiple randomised controlled trial design: a simulation study.

Background: The cohort multiple randomised controlled trial (cmRCT) design provides an opportunity to incorporate the benefits of randomisation within clinical practice; thus reducing costs, integrating electronic healthcare records, and improving external validity. This study aims to address a key concern of the cmRCT design: refusal to treatment is only present in the intervention arm, and this may lead to bias and reduce statistical power.

Methods: We used simulation studies to assess the effect of this refusal, both random and related to event risk, on bias of the effect estimator and statistical power.

Cohort Multiple Randomised Controlled Trials (cmRCT) design: efficient but biased? A simulation study to evaluate the feasibility of the Cluster cmRCT design.

Background: The Cohort Multiple Randomised Controlled Trial (cmRCT) is a newly proposed pragmatic trial design; recently several cmRCT have been initiated. This study tests the unresolved question of whether differential refusal in the intervention arm leads to bias or loss of statistical power and how to deal with this.

Methods: We conduct simulations evaluating a hypothetical cluster cmRCT in patients at risk of cardiovascular disease (CVD).

Collider Bias Is Only a Partial Explanation for the Obesity Paradox.

Background: "Obesity paradox" refers to an association between obesity and reduced mortality (contrary to an expected increased mortality). A common explanation is collider stratification bias: unmeasured confounding induced by selection bias. Here, we test this supposition through a realistic generative model.

The jurisprudential nature of fraud in biomedical publishing.

When instances of fraud in biomedical publishing come to light there is widespread indignation, not least because the consequences seem usually only to be internal enquiries and professional displeasure. A number of bodies have been constituted to improve publishing ethics and but these are largely advisory. Potentially though, actions in the tort of deceit and negligence, possibly misfeasance in a public office, and loss of chance could be brought against those responsible.

The legality of slimming advertisements in Singapore.

Governments in newly affluent countries like Singapore perceive a growing obesity problem, which in turn attracts the attention of numerous suppliers of slimming aids of dubious value. Advertisements relating to these appear in many cases to breach the Sale of Food Act and the Medicines Act. Under these provisions, oral and transdermal slimming aids which are not prescription drugs or on the General Sales List must have a permit if they are to be advertised, which is granted if the authorities are satisfied as to the existence of evidence for efficacy.

Effects of shiitake (Lentinus edodes) extract on human neutrophils and the U937 monocytic cell line.

The aqueous extract of the shiitake mushroom was found to decrease IL-1 production and apoptosis in human neutrophils, as measured by ELISA and flow cytometry respectively. It was found to increase IL-1 production and apoptosis in the U937 monocytic cell line. The extract showed no significant effects on the superoxide production of both neutrophils and U937 cells, as measured by chemiluminescence.

Carnosine and anserine as modulators of neutrophil function.

Carnosine and anserine, the bioactive peptides found in most meats and fish, were tested for their ability to modulate neutrophil and U937 cell function, specifically with respect to respiratory burst, interleukin-1 beta production and apoptosis. Both peptides increased the respiratory burst and interleukin-1 beta production of human neutrophils but not of U937 cells. They suppressed apoptosis of human neutrophils but enhanced apoptosis of U937 cells as assessed by DNA strand breaks.

Genotype associations among seven apolipoprotein B polymorphisms in a population of Orang Asli of western Malaysia.

Associations among seven apolipoprotein B (APOB) gene polymorphisms [C-T promoter site; Leu-Ala-Leu signal peptide (SP) insertion/deletion; AG C,G site at codon 71; AG A1,D site at codon 591; XbaI site at codon 2488; AG H,I site at codon 3611; and AG T,Z site at codon 4154] were investigated in 195 members of an Orang Asli (aborigine) population from western Malaysia. Frequencies of the rare alleles for all these polymorphisms turned out to be low when compared with European but not Asian populations. The AG H,I site was not polymorphic.

Plasma lipids and apolipoproteins in a population of Orang Asli ('aborigines') from West Malaysia.

Plasma total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDLC) and apolipoproteins Al (apo Al) and B (apo B) were measured in a sample of subjects from the Semai tribe of Orang Asli in peninsular Malaysia. They appeared to exhibit the lowest TC ever recorded (1.6 for males and 1.

Antioxidants in food and chronic degenerative diseases.

Both preventive and chain breaking antioxidants have a role in the limitation of free radical damage. Some of these may be regarded as "classical", like vitamins E and C but others are more recently discovered, such as the flavonoids, widespread in plant tissues, and the muscle constituents anserine and carnosine. The major conditions in which the role of antioxidants is under intense investigation include coronary artery disease, cancer and diabetes.

Erythrocyte enzymes decomposing reactive oxygen species and gestational age.

Superoxide dismutase (SOD; EC 1.15.1.

Delta bilirubin changes following phototherapy for neonatal jaundice.

The effect of phototherapy for neonatal jaundice on the serum concentrations of total, unconjugated, conjugated and delta bilirubins were studied in 91 infants. Only unconjugated bilirubin concentration declined during phototherapy, from 254.7 +/- 7.

Effect of glucose on the respiratory burst of circulating neutrophils from asthmatics.

The respiratory burst is dependent on a source of glucose. We wished to investigate the effect of glucose on the superoxide production of circulating neutrophils. Superoxide production of neutrophils was significantly enhanced by glucose concentration of from 1 to 50 mmole/liter in the medium.

Effect of apolipoprotein E variants on plasma lipids and apolipoproteins in the Orang Asli ('aborigines') of Malaysia.

Members of the Semai group of Orang Asli ('aborigines') in peninsular Malaysia were examined for apolipoprotein E (apo E) variants in relation to plasma total cholesterol (TC), high density lipoprotein cholesterol, low density lipoprotein cholesterol (LDLC), triglycerides (TG), apolipoprotein AI and apolipoprotein B (apo B). The e2 and e4 alleles were found to be higher than in most other groups as reported. The sample as a whole was normotriglyceridaemic (mean plasma TG, 1.