The psychometric function describes how an experimental variable, such as stimulus strength, influences the behaviour of an observer. Estimation of psychometric functions from experimental data plays a central role in fields such as psychophysics, experimental psychology and in the behavioural neurosciences. Experimental data may exhibit substantial overdispersion, which may result from non-sta...

BACKGROUND Psychometric testing is used to identify patients with cirrhosis who have developed hepatic encephalopathy (HE). Most batteries consist of a series of paper-and-pencil tests, which are cumbersome for most clinicians. A modern, easy-to-use, computer-based battery would be a helpful clinical tool, given that in its minimal form, HE has an impact on both patients' quality of life and th...

This study systematically reviewed the clinical and psychometric properties of manual function outcome measures for children with developmental coordination disorder (DCD) aged 3-18 years. Three electronic databases were searched to identify manual function tools at the ICF-CY body function, activity and participation level used in children with DCD. Study selection and data extraction was cond...

BACKGROUND Depression can interfere with the normal expression of cognitive abilities in adults of all ages, but it is unclear if depression in demented people, which is common, is associated with reduced cognitive performance beyond the effect of the dementia itself. OBJECTIVE To determine if depression adds to the cognitive deficit in dementia. DESIGN Performance on psychometric tests of ...

Several English and Spanish language tests currently used in bilingual education and some less known tests are reviewed, looking at both historic and psychometric factors. It is suggested that practitioners have commonly assumed that all language tests are basically valid, which contributed to the commercial success of some tests of questionable validity, ill-suited to the purpose of educationa...

The psychometric function relates an observer's performance to an independent variable, usually some physical quantity of a stimulus in a psychophysical task. This paper, together with its companion paper (Wichmann & Hill, 2001), describes an integrated approach to (1) fitting psychometric functions, (2) assessing the goodness of fit, and (3) providing confidence intervals for the function's pa...

The therapeutic efficacy of orally administered branched-chain amino acids in patients with liver cirrhosis and chronic encephalopathy was examined in a double blind, randomised crossover study. Seven patients with manifest hepatic cirrhosis and encephalopathy of six months' duration or longer ingested 30 g branched-chain amino acids or placebo during two 14-day periods. Psychometric tests and ...

[Purpose] The evaluation of sitting balance is important for the prevention of falls in older adults, especially those who have a disability involving the lower extremities. However, no studies have been designed to assess a patient's dynamic sitting balance using a sequential protocol. The objective of this study was to investigate the psychometric properties of the sequential weight-shifting ...