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Objective: The purpose of this study was to accumulate behavioral validity evidence for physical activity Stage of Change (SOC)., Design: Nine studies used a common physical activity SOC measure and examined self-report, objective, and performance physical activity indicators to accumulate behavioral validity evidence for SOC. Type of measure, the strength of the expected relationship between the measure and SOC, and the predicted SOC differences were examined. Validity evidence for the SOC was also examined by population and sampling method., Main Outcome Measures: Validity evidence for physical activity SOC was classified with respect to the type of measurement instrument and the hypothesized magnitude of the relationship between the measure and the SOC., Results: Physical activity SOC was found to be behaviorally valid as evidenced by self-reported physical activity, self-reported exercise, self-reported sedentary behaviors, pedometers, and physical functioning. Physical activity SOC does not appear to be related to physical fitness or weight indicators., Conclusions: This study highlights a successful multi-site collaboration. Physical activity data from nine large-scale, health trials was combined and accumulated behavioral validation evidence for the physical activity SOC., ((Copyright) 2008 APA.)

A. Bellg, B. Borrelli, et al. (2004) previously developed a framework that consisted of strategies to enhance treatment fidelity of health behavior interventions. The present study used this framework to (a) develop a measure of treatment fidelity and (b) use the measure to evaluate treatment fidelity in articles published in 5 journals over 10 years. Three hundred forty-two articles met inclusion criteria; 22% reported strategies to maintain provider skills, 27% reported checking adherence to protocol, 35% reported using a treatment manual, 54% reported using none of these strategies, and 12% reported using all 3 strategies. The mean proportion adherence to treatment fidelity strategies was .55; 15.5% of articles achieved greater than or equal to .80. This tool may be useful for researchers, grant reviewers, and editors planning and evaluating trials., (((c) 2005 APA, all rights reserved).)

Purpose: To evaluate prospectively the safety and effectiveness of aortoiliac magnetic resonance (MR) angiography enhanced with MS-325 (gadofosveset trisodium) at a dose of 0.03 mmol/kg; effectiveness was defined as accuracy relative to the reference standard, conventional angiography., Materials and Methods: Study was approved by institutional review boards of participating institutions, and required national approvals were obtained. Study protocol conformed to Good Clinical Practice guidelines, and informed patient consent was obtained. Patients with known or suspected peripheral vascular disease received 0.03 mmol/kg MS-325 for aortoiliac MR angiography. They were also examined with conventional angiography. MS-325-enhanced MR was evaluated for safety and effectiveness. Along with unenhanced two-dimensional time-of-flight MR angiography, it was compared with conventional angiography for presence of vascular stenosis. Student t tests were used to identify significant improvement in diagnostic sensitivity, specificity, and accuracy, as well as quantitative characterization of stenoses by three blinded readers. Correlations between readers of conventional angiograms were calculated and compared with MR results., Results: In 174 patients, MS-325-enhanced MR angiography showed significant improvement (P < or = .001) in sensitivity, specificity, and accuracy for diagnosis of clinically significant (> or =50%) stenosis, compared with unenhanced MR. For all readers, areas under the receiver operating characteristic curve for both quantitative and qualitative measures of significant disease increased (P < .001) for MS-325-enhanced MR compared with time-of-flight MR. All readers also expressed higher confidence in diagnosis (P < .001) and found fewer images uninterpretable with MS-325 enhancement. All measures of interpretation accuracy approached corresponding measures of correlation between readers of conventional angiograms. Incidence of severe and serious adverse events with MS-325 was low. No patients were withdrawn from study due to adverse events or abnormalities in laboratory results. There were no clinically important trends in findings at hematology, blood chemistry, urinalysis, electrocardiography, or physical examination., Conclusion: MR angiography with MS-325 provides significant improvement in effectiveness over unenhanced MR (and minimal and transient side effects) at a dose of 0.03 mmol/kg and was safe and effective for MR evaluation of patients with aortoiliac occlusive disease.

The purpose of this study was to identify the population prevalence across the stages of change (SoC) for regular physical activity and to establish the prevalence of people at risk. With support from the National Institutes of Health, the American Heart Association, and the Robert Wood Johnson Foundation, nine Behavior Change Consortium studies with a common physical activity SoC measure agreed to collaborate and share data. The distribution pattern identified in these predominantly reactively recruited studies was Precontemplation (PC) = 5% (+/- 10), Contemplation (C) = 10% (+/- 10), Preparation (P) = 40% (+/- 10), Action = 10% (+/- 10), and Maintenance = 35% (+/- 10). With reactively recruited studies, it can be anticipated that there will be a higher percentage of the sample that is ready to change and a greater percentage of currently active people compared to random representative samples. The at-risk stage distribution (i.e., those not at criteria or PC, C, and P) was approximately 10% PC, 20% C, and 70% P in specific samples and approximately 20% PC, 10% C, and 70% P in the clinical samples. Knowing SoC heuristics can inform public health practitioners and policymakers about the population's motivation for physical activity, help track changes over time, and assist in the allocation of resources.

Treatment fidelity plays an important role in the research team's ability to ensure that a treatment has been implemented as intended and that the treatment has been accurately tested. Developing, implementing, and evaluating a treatment fidelity plan can be challenging. The treatment fidelity workgroup within the Behavior Change Consortium (BCC) developed guidelines to comprehensively evaluate treatment fidelity in behavior change research. The guidelines include evaluation of treatment fidelity with regard to study design, training of interventionists, delivery and receipt of the intervention, and enactment of the intervention in real-life settings. This article describes these guidelines and provides examples from four BCC studies as to how these recommended guidelines for fidelity were considered. Future work needs to focus not only on implementing treatment fidelity plans but also on quantifying the evaluations performed, developing specific criteria for interpretation of the findings, and establishing best practices of treatment fidelity.

Nuclear magnetic resonance pixel intensity and contrast-to-noise has been computed and presented in graphical form for various tissues in the normal central nervous system, on the assumption that the signal intensity is proportional to the macroscopic transverse spin magnetization at the time of detection. T1, T2, and spin density values were experimentally determined using chi-square minimization techniques. Additionally, spin density was derived from partial saturation scans obtained with a long repetition time compared with the spin-lattice relaxation time. Pulse sequences discussed comprise partial saturation, saturation recovery, spin echo, and Carr- Purcell - Meiboom -Gill ( CPMG ). The complicated dependence of signal and contrast-to-noise on the pulse timing parameters and the specific pulse sequence makes it appear desirable to display image intensity so that the dependence on the extrinsic (operator-selectable parameter) is eliminated. Whereas T2 images can be derived from CPMG scans without excessive time penalty, this is not the case for T1 and spin density.