Dealing with missing standard deviation and mean values in meta-analysis of continuous outcomes: a systematic review.

Background: Rigorous, informative meta-analyses rely on availability of appropriate summary statistics or individual participant data. For continuous outcomes, especially those with naturally skewed distributions, summary information on the mean or variability often goes unreported. While full reporting of original trial data is the ideal, we sought to identify methods for handling unreported mean or variability summary statistics in meta-analysis.

Inter-arm blood pressure difference and mortality: a cohort study in an asymptomatic primary care population at elevated cardiovascular risk.

Background: Differences in blood pressure between arms are associated with increased cardiovascular mortality in cohorts with established vascular disease or substantially elevated cardiovascular risk.

Aim: To explore the association of inter-arm difference (IAD) with mortality in a community-dwelling cohort that is free of cardiovascular disease.

Design And Setting: Cohort analysis of a randomised controlled trial in central Scotland, from April 1998 to October 2008.

Oxygen saturation targets in infants with bronchiolitis (BIDS): a double-blind, randomised, equivalence trial.

Background: The American Academy of Pediatrics recommends a permissive hypoxaemic target for an oxygen saturation of 90% for children with bronchiolitis, which is consistent with the WHO recommendations for targets in children with lower respiratory tract infections. No evidence exists to support this threshold. We aimed to assess whether the 90% or higher target for management of oxygen supplementation was equivalent to a normoxic 94% or higher target for infants admitted to hospital with viral bronchiolitis.

Effect of a lifestyle intervention on weight change in south Asian individuals in the UK at high risk of type 2 diabetes: a family-cluster randomised controlled trial.

Background: The susceptibility to type 2 diabetes of people of south Asian descent is established, but there is little trial-based evidence for interventions to tackle this problem. We assessed a weight control and physical activity intervention in south Asian individuals in the UK.

Methods: We did this non-blinded trial in two National Health Service (NHS) regions in Scotland (UK).

Reduction of adverse effects from intravenous acetylcysteine treatment for paracetamol poisoning: a randomised controlled trial.

Background: Paracetamol poisoning is common worldwide. It is treated with intravenous acetylcysteine, but the standard regimen is complex and associated with frequent adverse effects related to concentration, which can cause treatment interruption. We aimed to ascertain whether adverse effects could be reduced with either a shorter modified acetylcysteine schedule, antiemetic pretreatment, or both.

Advancing care for traumatic brain injury: findings from the IMPACT studies and perspectives on future research.

Research in traumatic brain injury (TBI) is challenging for several reasons; in particular, the heterogeneity between patients regarding causes, pathophysiology, treatment, and outcome. Advances in basic science have failed to translate into successful clinical treatments, and the evidence underpinning guideline recommendations is weak. Because clinical research has been hampered by non-standardised data collection, restricted multidisciplinary collaboration, and the lack of sensitivity of classification and efficacy analyses, multidisciplinary collaborations are now being fostered.

Smoking, hypercholesterolaemia and hypertension as risk factors for cognitive impairment in older adults.

Background: the prevalence of all types of cognitive impairment, including dementia, is increasing but knowledge of aetiological factors is still evolving.

Objective: this study aimed to evaluate the association between cardiovascular risk factors and cognitive function in older persons.

Design, Setting And Subjects: a population-based cohort design involving 2,312 men and women (aged 50-75) enrolled in the University of Edinburgh Aspirin for Asymptomatic Atherosclerosis trial.

Prediction of outcome after moderate and severe traumatic brain injury: external validation of the International Mission on Prognosis and Analysis of Clinical Trials (IMPACT) and Corticoid Randomisation After Significant Head injury (CRASH) prognostic models.

Objective: The International Mission on Prognosis and Analysis of Clinical Trials and Corticoid Randomisation After Significant Head injury prognostic models predict outcome after traumatic brain injury but have not been compared in large datasets. The objective of this is study is to validate externally and compare the International Mission on Prognosis and Analysis of Clinical Trials and Corticoid Randomisation after Significant Head injury prognostic models for prediction of outcome after moderate or severe traumatic brain injury.

Design: External validation study.

Does the extended Glasgow Outcome Scale add value to the conventional Glasgow Outcome Scale?

The Glasgow Outcome Scale (GOS) is firmly established as the primary outcome measure for use in Phase III trials of interventions in traumatic brain injury (TBI). However, the GOS has been criticized for its lack of sensitivity to detect small but clinically relevant changes in outcome. The Glasgow Outcome Scale-Extended (GOSE) potentially addresses this criticism, and in this study we estimate the efficiency gain associated with using the GOSE in place of the GOS in ordinal analysis of 6-month outcome.

Pain in patients attending a specialist cancer service: prevalence and association with emotional distress.

Context: We know little about how many outpatients of a modern cancer center suffer from clinically significant unrelieved pain and the characteristics of these patients to guide better care.

Objectives: To determine the prevalence of clinically significant pain (CSP) in the outpatients of a regional cancer center and the association with distress and other variables.

Methods: A secondary analysis of cross-sectional, self-reported and clinical data from 2768 patients reattending selected clinics of a regional National Health Service cancer center in the U.

Large between-center differences in outcome after moderate and severe traumatic brain injury in the international mission on prognosis and clinical trial design in traumatic brain injury (IMPACT) study.

Background: Differences between centers in patient outcome after traumatic brain injury are of importance for multicenter studies and have seldom been studied.

Objective: To quantify the differences in centers enrolling patients in randomized clinical trials (RCTs) and surveys.

Methods: We analyzed individual patient data from 9578 patients with moderate and severe traumatic brain injury enrolled in 10 RCTs and 3 observational studies.

Screening for major depression in cancer outpatients: the diagnostic accuracy of the 9-item patient health questionnaire.

Background: Systematic screening for depression has been recommended for patients who have medical conditions like cancer. The 9-item Patient Health Questionnaire (PHQ-9) is becoming widely used, but its diagnostic accuracy has not yet been tested in a cancer patient population. In this article, the authors report on the performance of the PHQ-9 as a screening instrument for major depressive disorder (MDD) in patients with cancer.

Aspirin for prevention of cardiovascular events in a general population screened for a low ankle brachial index: a randomized controlled trial.

Context: A low ankle brachial index (ABI) indicates atherosclerosis and an increased risk of cardiovascular and cerebrovascular events. Screening for a low ABI can identify an asymptomatic higher risk group potentially amenable to preventive treatments.

Objective: To determine the effectiveness of aspirin in preventing events in people with a low ABI identified on screening the general population.

A simulation study evaluating approaches to the analysis of ordinal outcome data in randomized controlled trials in traumatic brain injury: results from the IMPACT Project.

Background: Clinical trials in traumatic brain injury have a disappointing track record, with a long history of 'negative' Phase III trials. One contributor to this lack of success is almost certainly the low efficiency of the conventional approach to the analysis, which discards information by dichotomizing an ordinal outcome scale.

Purpose: Our goal was to evaluate the potential efficiency gains, which can be achieved by using techniques, which extract additional information from ordinal outcome data - the proportional odds model and the sliding dichotomy.

IMPACT recommendations for improving the design and analysis of clinical trials in moderate to severe traumatic brain injury.

Clinical trials in traumatic brain injury (TBI) pose complex methodological challenges, largely related to the heterogeneity of the population. The International Mission on Prognosis and Clinical Trial Design in TBI study group has explored approaches for dealing with this heterogeneity with the aim to optimize clinical trials in TBI. Extensive prognostic analyses and simulation studies were conducted on individual patient data from eight trials and three observational studies.

Association between raised inflammatory markers and cognitive decline in elderly people with type 2 diabetes: the Edinburgh Type 2 Diabetes Study.

Objective: To determine whether circulating levels of the inflammatory markers C-reactive protein (CRP), interleukin (IL)-6, and tumor necrosis factor (TNF)-alpha are associated with cognitive ability and estimated lifetime cognitive decline in an elderly population with type 2 diabetes.

Research Design And Methods: A cross-sectional study of 1,066 men and women aged 60-75 years with type 2 diabetes and living in Lothian, Scotland (the Edinburgh Type 2 Diabetes Study), was performed. Seven cognitive tests were used to measure abilities in memory, nonverbal reasoning, information processing speed, executive function, and mental flexibility.

Baseline characteristics and statistical power in randomized controlled trials: selection, prognostic targeting, or covariate adjustment?

Objective: Heterogeneity of patients is a common problem in randomized controlled trials (RCTs) in various fields of clinical research. We aimed to investigate the potential benefits of different approaches for dealing with heterogeneity in a case study on traumatic brain injury (TBI).

Design And Setting: Statistical modeling studies in three surveys and six randomized controlled trials.

Patient and general practitioner preferences for the treatment of depression in patients with cancer: how, who, and where?

Objective: The objective of this study was to determine and compare patient and general practitioner (GP) preferences for the treatment of depression in patients with cancer.

Methods: A treatment preference questionnaire was completed by 100 patients who had been diagnosed with both cancer and major depressive disorder and by 86 GPs who had had experience of at least 1 patient with cancer and depression. Participants were asked to rank options for how depression should be treated, who should deliver the treatment, and where treatment should occur.

The influence of enrollment criteria on recruitment and outcome distribution in traumatic brain injury studies: results from the impact study.

Substantial heterogeneity exists among patients who suffer from traumatic brain injury (TBI). Strict enrollment criteria may diminish heterogeneity in randomized controlled trials (RCTs), but will also decrease recruitment and may affect the outcome distribution. The aim of this study was to investigate the influences of commonly used enrollment criteria for RCTs in TBI on potential recruitment and on outcome distribution.

Low dose aspirin and cognitive function in middle aged to elderly adults: randomised controlled trial.

Objective: To determine the effects of low dose aspirin on cognitive function in middle aged to elderly men and women at moderately increased cardiovascular risk.

Design: Randomised double blind placebo controlled trial.

Setting: Central Scotland.

Predicting outcome after traumatic brain injury: development and international validation of prognostic scores based on admission characteristics.

Background: Traumatic brain injury (TBI) is a leading cause of death and disability. A reliable prediction of outcome on admission is of great clinical relevance. We aimed to develop prognostic models with readily available traditional and novel predictors.

Effects of Glasgow Outcome Scale misclassification on traumatic brain injury clinical trials.

The Glasgow Outcome Scale (GOS) is the primary endpoint for efficacy analysis of clinical trials in traumatic brain injury (TBI). Accurate and consistent assessment of outcome after TBI is essential to the evaluation of treatment results, particularly in the context of multicenter studies and trials. The inconsistent measurement or interobserver variation on GOS outcome, or for that matter, on any outcome scales, may adversely affect the sensitivity to detect treatment effects in clinical trial.

What explains between-school differences in rates of sexual experience?

Background: Schools have the potential to influence their pupils' behaviour through the school's social organisation and culture, as well as through the formal curriculum. This paper provides the first attempt to explain the differences between schools in rates of reported heterosexual sexual experience amongst 15 and 16 year olds. It first examined whether variations in rates of sexual experience remained after controlling for the known predictors of sexual activity.