Psychometric validation of the work productivity and activity impairment questionnaire in ulcerative colitis: results from a systematic literature review.

Patients with ulcerative colitis, a type of inflammatory bowel disease, report negative impacts of disease symptoms on work-related outcomes, including absenteeism and presenteeism. As a way to better understand the impact of this disease and its treatment on work-related outcomes, the current review examines the use of the Work Productivity and Activity Impairment Questionnaire (WPAI), a patient-reported outcomes measure of absenteeism, presenteeism, and impairment in other activities, in studies of patients with ulcerative colitis. This review assesses the measurement properties of the WPAI in this patient population: its reliability, construct validity, ability to detect change, and responsiveness to effective treatments. Relevant data were extracted from 13 sources (journal articles and conference posters) identified following a systematic review of the published and gray literature. The evidence supports the WPAI as having test-retest reliability (reproducibility) over time; convergent validity, as indicated by moderate correlations with measures of quality of life and moderate-to-strong correlations with measures of disease activity; known-groups validity, as indicated by differences in WPAI scores between patients with active and inactive disease; ability (sensitivity) to detect change, as indicated by substantial improvement in scores for patients who achieve remission, accompanied by substantial worsening of scores for patients who relapse; and, responsiveness to treatment, with improvements in scores following treatments that reduce disease activity. Limitations included a lack of available evidence from randomized-controlled trials that could speak more directly to the WPAI's responsiveness to treatment. In conclusion, we recommend the use of the WPAI for measuring work outcomes in both observational studies and interventional trials that include patients with ulcerative colitis.

A meta-analytic review of measurement equivalence study findings of the SF-36® and SF-12® Health Surveys across electronic modes compared to paper administration.

PURPOSE: Patient-reported outcome (PRO) measures originally developed for paper administration are increasingly being administered electronically in clinical trials and other health research studies. Three published meta-analyses of measurement equivalence among paper and electronic modes aggregated findings across hundreds of PROs, but there has not been a similar meta-analysis that addresses a single PRO, partly because there are not enough published measurement equivalence studies using the same PRO. Because the SF-36(R) Health Survey (SF-36) is a widely used PRO, the aim of this study was to conduct a meta-analysis of measurement equivalence studies of this survey. METHODS: A literature search of several medical databases used search terms for variations of "SF-36" or "SF-12" and "equivalence" in the title or abstract of English language publications. The eight scale scores and two summary measures of the SF-36 and SF-12 were transformed to norm-based scores (NBS) using developer guidelines. A threshold of within ± 2 NBS points was set as the margin of equivalence. Comprehensive meta-analysis software was used. RESULTS: Twenty-five studies were included in the meta-analysis. Results indicated that mean differences across domains and summary scores ranged from 0.01 to 0.39 while estimates of agreement ranged from 0.76 to 0.91, all well within the equivalence threshold. Moderator analyses showed that time between administration, survey language, and type of electronic device did not influence equivalence. CONCLUSIONS: The results of the meta-analysis support equivalence of paper-based and electronic versions of the SF-36 and SF-12 across a variety of disease populations, countries, and electronic modes.

Frontostriatal and mediotemporal lobe contributions to implicit higher-order spatial sequence learning declines in aging and Parkinson's disease.

Sequence learning depends on the striatal system, but recent findings also implicate the mediotemporal lobe (MTL) system. Schendan, Searl, Melrose, and Stern (2003) found higher-order associative, learning-related activation in the striatum, dorsolateral prefrontal cortex, and the MTL during the early acquisition phase of both implicit and explicit variants of a serial response time task. This functional MRI (fMRI) study capitalized on this task to determine how changes in MTL function observed in aging and compromised frontostriatal function characteristic of patients with Parkinson's disease (PD) impacts sequence learning and memory under implicit instructions. Brain activity was compared between "sequence" and "random" conditions in 12 nondemented patients with PD and education- and gender-matched healthy control participants of whom 12 were age matched (MC) and 14 were younger (YC). Behaviorally, sequence-specific learning of higher-order associations was reduced with aging and changed further with PD and resulted primarily in implicit knowledge in the older participants. fMRI revealed reduced intensity and extent of sequence learning-related activation in older relative to younger people in frontostriatal circuits and the MTL. This was because signal was greater for the sequence than random condition in younger people, whereas older people, especially those with PD, showed the opposite pattern. Both older groups also showed increased activation to the task itself relative to baseline fixation. In addition, right MTL showed hypoactivation and left MTL hyperactivation in PD relative to the MC group. The results suggest changes in frontostriatal and MTL activity occur during aging that affect task-related activity and the initial acquisition phase of implicit higher-order sequence learning. In addition, the results suggest that Parkinson's disease adversely affects processes in the MTL including sequence learning and memory.

Object knowledge during entry-level categorization is activated and modified by implicit memory after 200 ms.

The timing of activating memory about visual objects is important for theories of human cognition but largely unknown, especially for tasks like entry level categorization that activate semantic memory. We tested an implicit memory-categorization "equivalence" hypothesis of multiple memory systems theory that a cortical system that stores structural knowledge to support entry level categorization also stores long-term, perceptual implicit memory, resulting in priming of this knowledge. Event-related brain potentials (ERPs) were recorded to impoverished pictures of new and repeated objects that were similar in perceptual properties but differed in categorization success. The cortical dynamics of object knowledge were defined using categorization ratings and naming. As predicted, rating, naming, and repetition effects on a frontocentral N350 show that implicit memory modifies the object knowledge network supporting categorization. This ERP is a complex of components between 200 and 500 ms indexing temporally overlapping substates from more perceptual to more conceptual knowledge. A frontopolar N350 subcomponent defines the first substate of a process of object model selection from occipitotemporal cortex based on shape similarity, and indicates that implicit memory in this system is greater with better categorization success. Afterwards, parietal positivity and a slow wave index secondary, post-model selection processes, like evaluating the success of a decision or memory match, and working memory for overt report, respectively. Altogether, ERP findings support the equivalence hypothesis and a two-state interactive account of visual object knowledge, and delineate the timing of multiple memory systems.