Transient errors are caused by variations in feelings, moods, and mental states over time. If these errors are present, coefficient alpha is an inflated estimate of reliability. A true-score model is presented that incorporates transient errors for test-retest data, and a reliability estimate is derived. This estimate, referred to as the test-retest alpha, is less than coefficient alpha if tran...

We investigated retest learning (i.e., performance improvement through retest practice) in the absence of item-specific effects (i.e., learning through memorizing or becoming familiar with specific items) with older adults. Thirty-one older adults (ages 60-82 years, M = 71.10, SD = 6.27) participated in an eight-session self-guided retest program. To eliminate item-specific effects, parallel ve...

Background: Positron emission tomography (PET) is a molecular imaging technology that enables in vivo quantification of metabolic activity or receptor density, among other applications. Examples of applications of PET imaging in neuroscience include studies of neuroreceptor/neurotransmitter levels in neuropsychiatric diseases (e.g., measuring receptor expression in schizophrenia) and of misfold...

Computerized neuropsychological testing has become an important tool in the identification and management of sports-related concussions; however, the psychometric effect of repeat testing has not been studied extensively beyond test-retest statistics. The current study analyzed data from Division I collegiate athletes who completed Immediate Post-Concussion Assessment and Cognitive Testing (ImP...

....... The Canadian Forces Aptitude Test (CFAT) retest policy required by Personnel Psychology Directive (PPD) 203 was changed on January 2007. Specifically, the length of the test-retest interval following the initial assessment was reduced from three months to seven days. Previous research suggests that when the length of the test-retest interval is short, an increase in test score on retest...

Test-retest performance on the Wechsler Adult Intelligence Scale (WAIS) of two groups of adult epilepsy patients are presented and compared. In one group, Seizures Improved (SI) group, seizure frequency had decreased during the test-retest interval, and in the other group, Seizures Unimproved (SU) group, the number of seizures had either increased or stayed the same over the test-retest interva...

INTRODUCTION Benign paroxysmal positional vertigo (BPPV) is the most common cause of peripheral vestibular dysfunction. OBJECTIVE To assess whether the performance of the Dix-Hallpike maneuver after the Epley positioning maneuver has prognostic value in the evolution of unilateral ductolithiasis of posterior semicircular canal. METHODS A prospective cohort study in monitored patients at oto...

OBJECTIVE Self-reported information from questionnaires is frequently used in epidemiological studies, but few of these studies provide information on the reproducibility of individual items contained in the questionnaire. We studied the test-retest reliability of self-reported diabetes among 33,919 participants in Norwegian Women and Cancer Study. METHODS The test-retest reliability of self-...