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Charles Warlow

Publications and source records attributed to Charles Warlow.

16 recordsLinked to original sources
PubMed2005

Bias from requiring explicit consent from all participants in observational research: prospective, population based study.

OBJECTIVE: To evaluate the differences between adults who consent to participate in observational research, and those who do not. DESIGN: Prospective, population based cohort study. SETTING: Primary and secondary care throughout Scotland. PARTICIPANTS: 187 adults (aged > or = 16 years) resident in Scotland at the time of their first diagnosis of a brain arteriovenous malformation in 1999-2002. INTERVENTION: Postal consent form sent via participants' general practitioner. MAIN OUTCOME MEASURES: Differences between consenters and non-consenters in demographic and clinical features at first presentation, and outcome during follow-up. RESULTS: 111 adults (59%) consented to participate in the study. These consenters were not significantly different from non-consenters in age, sex, or socioeconomic status at first presentation. However, consenters were significantly more likely than non-consenters to present alive and independent, and with a seizure. During follow-up, consenters were significantly more likely to receive interventional treatment. Although consenters' survival was significantly better, they were more likely to have a seizure during follow-up. Presentation with intracranial haemorrhage conferred a higher risk of subsequent haemorrhage when the whole cohort was analysed, but not when it was restricted to consenters. CONCLUSIONS: We have found differences between adults who consent to participate in observational records-based research and those who do not, or cannot, consent. Blanket requirements for explicit consent for the use of individuals' identifiable data can bias disease registers, epidemiological studies, and health services research.

Adolescent↗
PubMed2005

Systematic review of misdiagnosis of conversion symptoms and "hysteria".

OBJECTIVE: Paralysis, seizures, and sensory symptoms that are unexplained by organic disease are commonly referred to as "conversion" symptoms. Some patients who receive this diagnosis subsequently turn out to have a disease that explains their initial presentation. We aimed to determine how frequently this misdiagnosis occurs, and whether it has become less common since the widespread availability of brain imaging. DESIGN: Systematic review. DATA SOURCES: Medline, Embase, PsycINFO, Cinahl databases, and searches of reference lists. REVIEW METHODS: We included studies published since 1965 on the diagnostic outcome of adults with motor and sensory symptoms unexplained by disease. We critically appraised these papers, and carried out a multivariate, random effect, meta-analysis of the data. RESULTS: Twenty seven studies including a total of 1466 patients and a median duration of follow-up of five years were eligible for inclusion. Early studies were of poor quality. There was a significant (P < 0.02) decline in the mean rate of misdiagnosis from the 1950s to the present day; 29% (95% confidence interval 23% to 36%) in the 1950s; 17% (12% to 24%) in the 1960s; 4% (2% to 7%) in the 1970s; 4% (2% to 6%) in the 1980s; and 4% (2% to 6%) in the 1990s. This decline was independent of age, sex, and duration of symptom in people included in the studies. CONCLUSIONS: A high rate of misdiagnosis of conversion symptoms was reported in early studies but this rate has been only 4% on average in studies of this diagnosis since 1970. This decline is probably due to improvements in study quality rather than improved diagnostic accuracy arising from the introduction of computed tomography of the brain.

Adolescent↗
PubMed2003

Stroke.

Stroke is a major public-health burden worldwide. Prevention programmes are essential to reduce the incidence of stroke and to prevent the all but inevitable stroke epidemic, which will hit less developed countries particularly hard as their populations age and adopt lifestyles of the more developed countries. Efficient, effective, and rapid diagnosis of stroke and transient ischaemic attack is crucial. The diagnosis of the exact type and cause of stroke, which requires brain imaging as well as traditional clinical skills, is also important when it will influence management. The treatment of acute stroke, the prevention and management of the many complications of stroke, and the prevention of recurrent stroke and other serious vascular events are all improving rapidly. However, stroke management will only be most effective when delivered in the context of an organised, expert, educated, and enthusiastic stroke service that can react quickly to the needs of patients at all stages from onset to recovery.

Acute Disease↗
PubMed2002

Predicting outcome after acute and subacute stroke: development and validation of new prognostic models.

BACKGROUND AND PURPOSE: Statistical models to predict the outcome of patients with acute and subacute stroke could have several uses, but no adequate models exist. We therefore developed and validated new models. METHODS: Regression models to predict survival to 30 days after stroke and survival in a nondisabled state at 6 months were produced with the use of established guidelines on 530 patients from a stroke incidence study. Three models were produced for each outcome with progressively more detailed sets of predictor variables collected within 30 days of stroke onset. The models were externally validated and compared on 2 independent cohorts of stroke patients (538 and 1330 patients) by calculating the area under receiver operating characteristic curves (AUC) and by plotting calibration graphs. RESULTS: Models that included only 6 simple variables (age, living alone, independence in activities of daily living before the stroke, the verbal component of the Glasgow Coma Scale, arm power, ability to walk) generally performed as well as more complex models in both validation cohorts (AUC 0.84 to 0.88). They had good calibration but were overoptimistic in patients with the highest predicted probabilities of being independent. There were no differences in AUCs between patients seen within 48 hours of stroke onset and those seen later; between ischemic and hemorrhagic strokes; and between those with and without a previous stroke. CONCLUSIONS: The simple models performed well enough to be used for epidemiological purposes such as stratification in trials or correction for case mix. However, clinicians should be cautious about using these models, especially in hyperacute stroke, to influence individual patient management until they have been further evaluated. Further research is required to test whether additional information from brain imaging improves predictive accuracy.

Acute Disease↗
PubMedDate not supplied

UK neurologists and the care of adults with acute neurological problems.

In the UK, most patients admitted to hospital with acute neurological problems are not looked after or even seen by a consultant neurologist. As a result, the outcome of their care may be suboptimal. The Association of British Neurologists believes that, in order to provide a reasonable service, the number of consultant neurologists will have to increase more than threefold, to about 1,400. This should be achievable in the next 10-15 years and would bring UK neurological services up to the standards that already obtain in comparable European countries.

Clinical Competence↗
PubMedDate not supplied

Over-regulation of clinical research: a threat to public health.

Clinical research is subject to increasing regulation by research ethics committees and research and development offices which are responding to social and political pressures, as well as to new legislation, both European and national, some of which is still being worked out. The resulting bureaucracy, expense and confusion are putting insuperable hurdles in the way of clinical research and clinical care is compromised. What research is still possible will only be done in large organisations and may even be seriously biased. The solutions are to inform and seek the help of the public and to forge alliances with patient groups. Patients have far more to lose than clinical researchers who, if clinically qualified, can more easily pursue a fulfilling career as clinicians rather than researchers.

Biomedical Research↗