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BACKGROUND & AIMS: "Academic detailing" is an effective strategy for promoting the use of screening sigmoidoscopy by primary care physicians. The primary objectives of this study were to determine whether the sustained presence of an "outside" university-based gastroenterologist performing on-site screening sigmoidoscopy promoted long-term utilization and whether the provision for on-site sigmoidoscopy was an effective venue for training primary care endoscopists. METHODS: Nine urban community health centers, including 4 intervention and 5 control sites, participated in a nonrandomized controlled trial conducted over 3 years. RESULTS: By the end of year 3, overall self-reported use of screening sigmoidoscopy increased by 61% for the intervention group vs. only 25% for the comparison group (P = 0.001). Ninety-seven percent of those reporting compliance referred 1 or more asymptomatic average-risk patients for screening examinations. Only 2 of 83 (2.4%) eligible providers completed on-site training and continued performing screening examinations independently. The major barriers to participation included lack of interest, lack of time to learn or perform sigmoidoscopy, concerns about technical competence, and lack of need because of on-site availability. CONCLUSIONS: Maintenance of on-site screening sigmoidoscopy services performed by an outside gastroenterologist promotes long-term utilization but fails as venue for training primary care endoscopists. Alternative strategies for expanding capacity are needed.  相似文献   
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Background

Interventions to increase sustained physical activity are needed and should be based on proven theories.

Purpose

To gain a better understanding of the correlates of sustained physical activity in midlife women, we used longitudinal epidemiologic data to investigate links between sustained physical activity and constructs advocated by three basic behavioral and social science theories: (1) self-determination, (2) social cognitive, and (3) social networks. A random sample of 90 midlife women, stratified by level of physical activity over 15 years, was selected from the Chicago cohort of the Longitudinal Study of Women’s Health Across the Nation (SWAN).

Methods

Using data on self-reported physical activity collected over 15 years, women were categorized into consistently active, sporadically active, and sedentary. New data were collected on theory-relevant constructs, i.e., autonomous motivation (assessed by the Treatment Self-Regulation Questionnaire) and self-efficacy (assessed by the Self-Efficacy and Exercise Habits Survey). Every SWAN woman identified a close female friend who also completed the physical activity questionnaire.

Results

SWAN women with higher autonomous motivation (p?=?0.002) and higher self-efficacy (p?<?0.001) were more likely to be consistently physically active in analyses adjusted for age, race, and socioeconomic status. Sixty-one percent of SWAN women with a history of consistent physical activity had a friend who is currently highly active, versus 38 and 23 % for sporadically active and sedentary women, respectively (test for trend p?=?0.008).

Conclusion

In midlife women, constructs advocated by basic behavioral and social science theories were consistent with long-term patterns of physical activity behavior. Special focus should be given to these basic theories in the design of interventions to promote sustained physical activity in mid-life women.  相似文献   
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One of the popular designs for the distal extension partial removable dental prosthesis is the RPI clasp assembly. A modification of the RPI clasp assembly is introduced. It incorporates a mesial rest (R), proximal plate (P), and a horizontal retentive arm (H—RPH). This clasp assembly provides benefits of the RPI clasp and can be used in clinical situations where the RPI clasp is contraindicated.  相似文献   
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