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The development and implementation of school policies is considered a key strategy for the promotion of physical activity (PA) in children and adolescents. This study aimed to systematically review and synthesise existing literature focusing on the associations between formal written school-based PA policies and (a) school PA practices and (b) PA behaviours of school-aged children and adolescents. Fifty-one papers reporting on 52 studies met the eligibility criteria. All but two studies were from high income countries, most used cross-sectional designs and demonstrated fair methodological quality, and just over a third examined language aspects of policies. Findings predominantly indicated a lack of or inconclusive associations between the various characteristics examined and PA outcomes. Inconclusive associations were identified between both PA practice and behaviour outcomes and state level policies, policies focusing on PE and school-day PA, and in studies examining language aspects of policies. Inconclusive associations with both types of outcomes were more likely to be identified compared to a lack of associations in studies using self-report measures and in studies not providing information about the quality of exposure and outcome measures used. Overall, findings highlight the need for further research that acknowledges the complex relationship between school policies and PA outcomes and employs robust methodological approaches to enhance our understanding of this area.  相似文献   
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Purpose

A hydrogel rectal spacer (HRS) is a medical device that is approved by the U.S. Food and Drug Administration to increase the separation between the prostate and rectum. We conducted a cost-effectiveness analysis of HRS use for reduction in radiation therapy (RT) toxicities in patients with prostate cancer (PC) undergoing external beam RT (EBRT).

Methods and Materials

A multistate Markov model was constructed from the U.S. payer perspective to examine the cost-effectiveness of HRS in men with localized PC receiving EBRT (EBRT alone vs EBRT + HRS). The subgroups analyzed included site of HRS placement (hospital outpatient, physician office, ambulatory surgery center) and proportion of patients with good baseline erectile function (EF). Data on EF, gastrointestinal and genitourinary toxicities incidence, and potential risks associated with HRS implantation were obtained from a recently published randomized clinical trial. Health utilities and costs were derived from the literature and the 2018 Physician Fee Schedule and were discounted 3% annually. Quality-adjusted life years (QALYs) and costs were modeled for a 5-year period from receipt of RT. Probabilistic sensitivity analysis and value-based threshold analyses were conducted.

Results

The per-patient 5-year incremental cost for spacers administered in a hospital outpatient setting was $3578, and the incremental effectiveness was 0.0371 QALYs. The incremental cost-effectiveness ratio was $96,440/QALY for patients with PC undergoing HRS insertion in a hospital and $39,286/QALY for patients undergoing HRS insertion in an ambulatory facility. For men with good baseline EF, the incremental cost-effectiveness ratio was $35,548/QALY and $9627/QALY in hospital outpatient and ambulatory facility settings, respectively.

Conclusions

Based on the current Medicare Physician Fee Schedule, HRS is cost-effective at a willingness to pay threshold of $100,000. These results contain substantial uncertainty, suggesting more evidence is needed to refine future decision-making.  相似文献   
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