Transformation of indwelling peritoneal catheter placement for malignant ascites from an inpatient to a day-case service: analysis of patient risk and financial implication.

AIM: To investigate the impact on patient outcomes, costs, and resources/infrastructure of inserting indwelling peritoneal catheters (IPC) during a day-case instead of an inpatient service. MATERIALS AND METHODS: A single-centre, retrospective analysis of patients receiving IPCs over a 4-year period was performed. Patients undergoing a day-case procedure were admitted in the morning for pre-procedural investigations, a 15.5 F PleurX IPC (BD, Wokingham, UK) was inserted, all accessible fluid drained and patients discharged the same day, barring any complications. Using electronic patient records, outcomes and complications (immediate/post-procedural) were recorded. Expenses and re-imbursement tariffs were obtained from the income department. RESULTS: Of 138 IPC procedures, 45.6% were undertaken after formal inpatient admission, 54.3% were undertaken as a day-case. The mean hospital stay was 2.51 bed-days for inpatient procedures (n=63) and 0.31 bed-days for day-case procedures (n=75; p<0.001). Day-case procedures saved 165 bed-days per year. Complication rates were 15.9% and 16% for inpatient and day-case procedures respectively (p=0.98). There was an estimated savings of £1,850.46 per day-case procedure or £138,784.50 annually. CONCLUSION: The placement of IPCs can safely be performed as a day-case procedure. There were substantial economic benefits as well as improved patient satisfaction, with no compromise in patient outcomes. Day-case IPC insertion is now standard practice at The Christie NHS Trust.

Building a Networked Improvement Community: Lessons in Organizing to Promote Diversity, Equity, and Inclusion in Science, Technology, Engineering, and Mathematics.

In 2016, 10 universities launched a Networked Improvement Community (NIC) aimed at increasing the number of scholars from Alliances for Graduate Education and the Professoriate (AGEP) populations entering science, technology, engineering, and mathematics (STEM) faculty careers. NICs bring together stakeholders focused on a common goal to accelerate innovation through structured, ongoing intervention development, implementation, and refinement. We theorized a NIC organizational structure would aid understandings of a complex problem in different contexts and accelerate opportunities to develop and improve interventions to address the problem. A distinctive feature of this NIC is its diverse institutional composition of public and private, predominantly white institutions, a historically Black university, a Hispanic-serving institution, and land grant institutions located across eight states and Washington, DC, United States. NIC members hold different positions within their institutions and have access to varied levers of change. Among the many lessons learned through this community case study, analyzing and addressing failed strategies is as equally important to a healthy NIC as is sharing learning from successful interventions. We initially relied on pre-existing relationships and assumptions about how we would work together, rather than making explicit how the NIC would develop, establish norms, understand common processes, and manage changing relationships. We had varied understandings of the depth of campus differences, sometimes resulting in frustrations about the disparate progress on goals. NIC structures require significant engagement with the group, often more intensive than traditional multi-institution organizational structures. They require time to develop and ongoing maintenance in order to advance the work. We continue to reevaluate our model for leadership, climate, diversity, conflict resolution, engagement, decision-making, roles, and data, leading to increased investment in the success of all NIC institutions. Our NIC has evolved from the traditional NIC model to become the Center for the Integration of Research, Teaching and Learning (CIRTL) AGEP NIC model with five key characteristics: (1) A well-specified aim, (2) An understanding of systems, including a variety of contexts and different organizations, (3) A culture and practice of shared leadership and inclusivity, (4) The use of data reflecting different institutional contexts, and (5) The ability to accelerate infrastructure and interventions. We conclude with recommendations for those considering developing a NIC to promote diversity, equity, and inclusion efforts.

Competition between Allowed and First-Forbidden ß Decay: The Case of

The ß decay of ^{208}Hg into the one-proton hole, one neutron-particle _{81}^{208}Tl_{127} nucleus was investigated at CERN-ISOLDE. Shell-model calculations describe well the level scheme deduced, validating the proton-neutron interactions used, with implications for the whole of the N>126, Z<82 quadrant of neutron-rich nuclei. While both negative and positive parity states with spin 0 and 1 are expected within the Q_{ß} window, only three negative parity states are populated directly in the ß decay. The data provide a unique test of the competition between allowed Gamow-Teller and Fermi, and first-forbidden ß decays, essential for the understanding of the nucleosynthesis of heavy nuclei in the rapid neutron capture process. Furthermore, the observation of the parity changing 0^{+}→0^{-}ß decay where the daughter state is core excited is unique, and can provide information on mesonic corrections of effective operators.

The short-term effects of a mass reach physical activity campaign: an evaluation using hierarchy of effects model and intention profiles.

BACKGROUND: Mass reach physical activity campaigns are designed to deliver physical-activity related messages to a large population across different media including print, television, radio, and websites. Few evaluations have examined the short-term effects of a mass reach campaign on participants who were engaged with the campaign. The current research examined the short-term effects of the ParticipACTION 150 Play List, a mass reach physical activity campaign, on participants who registered with the campaign website. METHODS: Participants (N = 7801) completed a registration questionnaire measuring demographic information, awareness and recall of physical activity and sport advertising, and self-reported number of activities tried or planned to try from the 150 Play List. A follow-up survey was completed by 1298 participants from the original sample. Additional questions assessed experience with the 150 Play List and attitudes towards campaign advertisements. RESULTS: Approximately 14.5% of participants cited the ParticipACTION 150 Play List and 23.6% mentioned a 'getting active' message when recalling advertisements. Those who named the 150 Play List or getting active reported more activities tried and more activities planned than those who did not. They were also more likely to say they had tried a new activity and planned ongoing participation. It was also found that participants with a disability were more likely to have tried a new activity compared to those not in a minority group. Other correlates of trying new activities at follow-up were younger age, more positive reported experience with the 150 Play List, and more favourable attitudes towards campaign advertisements. Those who did not intend continued participation, or who were unsure at baseline and then decided against continued participation at follow-up, reported they were less sedentary or encouraging others to be active. CONCLUSIONS: This research addresses the gap in evidence regarding the efficacy of mass reach physical activity campaigns by informing whether a year-long campaign like the 150 Play List can be effective in influencing the behavior of those engaged with the campaign. The results reinforce the idea that 'top of mind' awareness should be measured. Investigating intention profiles can help inform campaign impacts and continuation intentions.

First Accurate Normalization of the ß-delayed α Decay of

The ^{12}C(α,γ)^{16}O reaction plays a central role in astrophysics, but its cross section at energies relevant for astrophysical applications is only poorly constrained by laboratory data. The reduced α width, γ_{11}, of the bound 1^{-} level in ^{16}O is particularly important to determine the cross section. The magnitude of γ_{11} is determined via sub-Coulomb α-transfer reactions or the ß-delayed α decay of ^{16}N, but the latter approach is presently hampered by the lack of sufficiently precise data on the ß-decay branching ratios. Here we report improved branching ratios for the bound 1^{-} level [b_{ß,11}=(5.02±0.10)×10^{-2}] and for ß-delayed α emission [b_{ßα}=(1.59±0.06)×10^{-5}]. Our value for b_{ßα} is 33% larger than previously held, leading to a substantial increase in γ_{11}. Our revised value for γ_{11} is in good agreement with the value obtained in α-transfer studies and the weighted average of the two gives a robust and precise determination of γ_{11}, which provides significantly improved constraints on the ^{12}C(α,γ) cross section in the energy range relevant to hydrostatic He burning.

What older adolescents expect from physical activity: Implicit cognitions regarding health and appearance outcomes.

OBJECTIVE: To explore older adolescents' reflective and impulsive thoughts about health- and social/appearance-related physical activity (PA) outcomes and investigate how those thoughts relate to their PA behavior. PARTICIPANTS: One hundred and forty-four undergraduate students (109 women; 35 men) aged 17-19 years (M = 18.11, SD = 0.65) participated in this study in October 2015. METHODS: Participants completed a Go/No-go Association Task that assessed automaticity of associations between PA words and either health outcomes or social/appearance outcomes. Questionnaires assessing PA behavior, attitudes, outcome expectations, and body image were also completed. RESULTS: Participants demonstrated a positive automatic association between PA and social/appearance outcomes, F(1, 136) = 4.403, p < .05, η2 = .031, but they showed no difference in their associations between PA and desirable or undesirable health outcomes, F(1, 136) = 2.405, p = .123, η2 = .017. CONCLUSIONS: Older adolescents implicitly attend to the social/appearance outcomes of PA more than potential health outcomes, indicating that social recognition and a desirable physique may be the key PA motivators for adolescents.

Enhanced Quadrupole and Octupole Strength in Doubly Magic

The first 2^{+} and 3^{-} states of the doubly magic nucleus ^{132}Sn are populated via safe Coulomb excitation employing the recently commissioned HIE-ISOLDE accelerator at CERN in conjunction with the highly efficient MINIBALL array. The ^{132}Sn ions are accelerated to an energy of 5.49 MeV/nucleon and impinged on a ^{206}Pb target. Deexciting γ rays from the low-lying excited states of the target and the projectile are recorded in coincidence with scattered particles. The reduced transition strengths are determined for the transitions 0_{g.s.}^{+}→2_{1}^{+}, 0_{g.s.}^{+}→3_{1}^{-}, and 2_{1}^{+}→3_{1}^{-} in ^{132}Sn. The results on these states provide crucial information on cross-shell configurations which are determined within large-scale shell-model and Monte Carlo shell-model calculations as well as from random-phase approximation and relativistic random-phase approximation. The locally enhanced B(E2;0_{g.s.}^{+}→2_{1}^{+}) strength is consistent with the microscopic description of the structure of the respective states within all theoretical approaches. The presented results of experiment and theory can be considered to be the first direct verification of the sphericity and double magicity of ^{132}Sn.

Improving thermoelectric performance of TiNiSn by mixing MnNiSb in the half-Heusler structure.

The thermoelectric properties of the n-type semiconductor TiNiSn were optimized by partial substitution with metallic MnNiSb in the half Heusler structure. Herein, we study the transport properties and intrinsic phase separation in the Ti1-xMnxNiSn1-xSbx system. The alloys were prepared by arc-melting and annealed at temperatures obtained from differential thermal analysis and differential scanning calorimetry results. The phases were characterized using powder X-ray diffraction patterns, energy-dispersive X-ray spectroscopy, and differential scanning calorimetry. After annealing, the majority phase was TiNiSn with some Ni-rich sites, and the minority phases were primarily Ti6Sn5, Sn and MnSn2. The Ni-rich sites were caused by Frenkel defects; this led to metal-like behavior in the semiconductor specimens at low temperature. For x ≤ 0.05 the samples showed an activated conduction, whereas for x > 0.05 they showed metallic character. The figure of merit for x = 0.05 was increased by 61% (zT = 0.45) in comparison with the pure TiNiSn.

The impact of HENRY on parenting and family lifestyle: A national service evaluation of a preschool obesity prevention programme.

OBJECTIVES: One in five children in England are overweight/obese at school entry. Tackling obesity is therefore a priority. Right from the Start with HENRY is a widely-commissioned programme delivered by trained facilitators to small groups of parents over eight weekly sessions. It is designed to provide parents of infants and preschool children with the skills, knowledge and confidence required for a healthier family lifestyle. The aim of this work was to investigate programme impact using data collected routinely for quality control purposes. STUDY DESIGN: Analysis of routinely collected pre-post data from programmes delivered in the UK from January 2012 to February 2014. METHODS: Data were analysed from 144 programmes, including questionnaires relating to parenting, family eating behaviours, dietary intake, and physical activity/screen time. RESULTS: Over 24 months, 1100 parents attended programmes running in 86 locations. 788 (72%) completed >5 sessions of whom 624 (79%) provided baseline and completion questionnaires. Parents reported increases in healthiness of family lifestyle, parenting attributes, and emotional wellbeing following attendance (all P < .001). Both parents and children were reported to have increased their daily fruit/vegetable consumption, and reduced their consumption of high fat/sugar foods (both P < .001). There were also positive changes in eating behaviours, physical activity (P < .001) and children's screen time (P < .001). CONCLUSIONS: Significant changes were reported in all domains similar to those reported in a previous, smaller study in locations selected for experience and quality. The HENRY approach appears to have a beneficial impact even when delivered at scale in non-selected locations. Such changes, if maintained, may serve to protect against later obesity.

Simulated Wear of Self-Adhesive Resin Cements.

One of the primary areas of concern with luting agents is marginal gap erosion and attrition. The purpose of this laboratory study was to evaluate bulk and marginal slit (gap) generalized wear of self-adhesive resin cements. Three self-adhesive resin cements were used in this study: G-CEM LinkAce (LA), Maxcem Elite (ME), and RelyX Unicem2 Automix (RU). A custom stainless-steel fixture with a cavity 4.5 mm in diameter and 4 mm deep was used for simulated generalized (bulk) wear. For simulated marginal gap wear, a two-piece stainless-steel custom fixture was designed with a slit (gap) 300 µm wide and 3 mm in length. For both wear models, 20 specimens each for each of the three adhesive cements were made for both light-cure and chemical-cure techniques. The cured cements were polished with a series of carbide papers to a 4000-grit surface and subjected to 100,000 cycles using the slit (gap) wear model and 400,000 cycles for generalized (bulk) wear in a Leinfelder-Suzuki (Alabama machine) wear simulator (maximum load of 78.5 N). Flat-ended stainless-steel antagonists were used in a water slurry of poly(methylmethacrylate) beads for simulation of generalized contact-free area wear with both wear models. Before and after the wear challenges, the specimens were profiled with a Proscan 2100 noncontact profilometer, and wear (volume loss [VL] and mean facet depth [FD]) was determined using AnSur 3D software. Two-way analysis of variance (ANOVA) and Tukey post hoc tests were used for data analysis for the two wear models. Scanning electron microscopy (SEM) was used to examine polished surfaces of the resin cements and the worn surfaces after the wear challenges. The two-way ANOVA of VL using the generalized (bulk) wear model showed a significant effect among the three resin cement materials for the factor of resin cement (p<0.001) and the interaction of the cement and cure method (p<0.001), but not for the cure method (p=0.465). The two-way ANOVA for FD also found a significant difference for the factor of resin cement (p<0.001) and the interaction of the resin cement and cure method (p<0.001), but not for the cure method (p=0.277). The simulated generalized (bulk) wear for the light-cure groups was as follows: VL (mm(3)): RU 0.631 (0.094), LA 0.692 (0.112), and ME 1.046 (0.141) and FD (µm): RU 43.6 (6.5), LA 47.0 (7.7), and ME 72.5 (9.9). The simulated generalized (bulk) wear for the chemical-cure groups was as follows: VL (mm(3)): LA 0.741 (0.105), RU 1.231 (0.234), and ME 1.305 (0.143) and FD (µm): LA 50.7 (7.2), RU 84.5 (16.1), and ME 91.7 (10.2). Simulated wear using the slit (gap) model for the light-cure groups was as follows: VL (mm(3)): RU 0.030 (0.006), LA 0.031 (0.006), and ME 0.041 (0.009) and FD (µm): RU 49.6 (5.7), LA 57.2 (8.4), and ME 70.9 (10.7). The wear values for the chemical-cure slit (gap) groups were as follows: VL (mm(3)): LA 0.031 (0.004), ME 0.038 (0.007), and RU 0.045 (0.009) and FD (µm): LA 53.9 (6.7), ME 63.5 (9.1), and RU 74.2 (12.9). Pearson correlation tests revealed a strong relationship between the two wear models for the light-cure groups and a good relationship for the chemical-cure groups. The observations using SEM showed differences in filler particle shape and size among the cements and the resultant effect of the wear challenges. The worn surfaces of each cement were essentially the same for both light-cure and chemical-cure methods. The bulk wear model and new slit (gap) model for evaluation of simulated generalized wear of luting agents demonstrated significant differences (p<0.05) in relative wear among three self-adhesive resin cements and between visible light- and chemical-cure techniques.

Exploring women's responses to online media coverage of weight loss surgery.

The purpose of this study was to understand the reactions of women to online news articles about weight loss surgery and related reader comments. Focus groups were conducted; open-ended questions were asked to elicit responses to existing online news media content related to weight loss surgery. The participants described the online articles as predominantly supportive of weight loss surgery and in response they expressed a desire to see more critical content, including different and competing perspectives. Participants felt the online comments represented extreme perspectives and were predominately negative. These were therefore not viewed as helpful or informative. Nevertheless, readers viewed comments as a form of entertainment. Because of the aggressive and anonymous nature of reader comments in response to online news stories, the participants did not feel comfortable leaving comments themselves on the news sites. Findings highlight the importance of gathering readers' perspectives in response to interactive media content and, in particular, health information.

Surface plasmon-enhanced transverse magnetic second-harmonic generation.

We present experimental studies on surface plasmon (SP) enhanced transverse magnetic second-harmonic generation (T-MSHG) in single-crystal iron films grown by molecular beam epitaxy at room temperature on MgO (001) substrates. We show that it is possible to achieve both strongly enhanced T-MSHG intensity and high magnetic contrast ratio under attenuated total reflection configuration without using complex heterostructures because MSHG is generated directly at the iron surface where SPs are present. The T-MSHG has a much larger contrast ratio than transverse magneto-optical Kerr effect (T-MOKE) and shows great potential for a new generation of bio-chemical sensors due to its very high surface sensitivity. In addition, by analyzing the experimental results and the simulations based on SP field-enhancement theory, we demonstrate that the second-order susceptibility of MSHG shows great anisotropy and the tensor χ(xzz)(odd) is dominant in our sample.

The pro-inflammatory effects of platelet contamination in plasma and mitigation strategies for avoidance.

BACKGROUND AND OBJECTIVES: Plasma and platelet concentrates are disproportionately implicated in transfusion-related acute lung injury (TRALI). Platelet-derived pro-inflammatory mediators, including soluble CD40 ligand (sCD40L), accumulate during storage. We hypothesized that platelet contamination induces sCD40L generation that causes neutrophil [polymorphonuclear leucocyte (PMN)] priming and PMN-mediated cytotoxicity. MATERIALS AND METHODS: Plasma was untreated, centrifuged (12,500 g) or separated from leucoreduced whole blood (WBLR) prior to freezing. Platelet counts and sCD40L concentrations were measured 1-5 days post-thaw. The plasma was assayed for PMN priming activity and was used in a two-event in vitro model of PMN-mediated human pulmonary microvascular endothelial cell (HMVEC) cytotoxicity. RESULTS: Untreated plasma contained 42±4·2×10(3)/µl platelets, which generated sCD40L accumulation (1·6-eight-fold vs. controls). Priming activity and HMVEC cytotoxicity were directly proportional to sCD40L concentration. WBLR and centrifugation reduced platelet and sCD40L contamination, abrogating the pro-inflammatory potential. CONCLUSION: Platelet contamination causes sCD40L accumulation in stored plasma that may contribute to TRALI. Platelet reduction is potentially the first TRALI mitigation effort in plasma manufacturing.

Rheological properties and microstructure of Cheddar cheese made with different fat contents.

Reduced- and low-fat cheeses are desired based on composition but often fall short on overall quality. One of the major problems with fat reduction in cheese is the development of a firm texture that does not break down during mastication, unlike that observed in full-fat cheeses. The objective of this investigation was to determine how the amount of fat affects the structure of Cheddar cheese from initial formation (2 wk) through 24 wk of aging. Cheeses were made with target fat contents of 3 to 33% (wt/wt) and moisture to protein ratios of 1.5:1. This allowed for comparisons based on relative amounts of fat and protein gel phases. Cheese microstructure was determined by confocal scanning laser microscopy combined with quantitative image analysis. Rheological analysis was used to determine changes in mechanical properties. Increasing fat content caused an increase in size of fat globules and a higher percentage of nonspherical globules. However, no changes in fat globules were observed with aging. Cheese rigidity (storage modulus) increased with fat content at 10°C, but differences attributable to fat were not apparent at 25°C. This was attributable to the storage modulus of fat approaching that of the protein gel; therefore, the amount of fat or gel phase did not have an effect on the cheese storage modulus. The rigidity of cheese decreased with storage and, because changes in the fat phase were not detected, it appeared to be attributable to changes in the gel network. It appeared that the diminished textural quality in low-fat Cheddar cheese is attributed to changes in the breakdown pattern during chewing, as altered by fat disrupting the cheese network.

Changes in BMI over 6 years: the role of demographic and neighborhood characteristics.

OBJECTIVE: To undertake a 6-year longitudinal investigation of the relationship between the built environment (perceived and objectively measured) and change in body mass index (BMI). Specifically, this research examined whether change in BMI was predicted by objectively measured neighborhood walkability and socioeconomic status (SES), and perceived neighborhood characteristics (for example, crime, traffic and interesting things to look at) in addition to other factors such as age, gender, education, physical activity, fruit and vegetable consumption and smoking. DESIGN: Longitudinal study. SUBJECTS: 500 adults who provided complete data in 2002 and 2008 and who did not move over the course of the study (47.8% female; age in 2002: 18-90 years). MEASUREMENTS: Telephone surveys in 2002 and 2008 measuring perceptions of their neighborhood environment and demographic factors. Objective measures of neighborhood characteristics were calculated using census data and geographical information systems in 2006. RESULTS: Age, neighborhood SES and perceived traffic were significantly related to increased BMI over the 6 years. Younger participants and those in lower SES neighborhoods were more likely to have increased BMI. Agreement with the statement that traffic made it difficult to walk also predicted increased BMI. CONCLUSION: This study adds to the literature to show that BMI increased in low SES neighborhoods. Although more research is needed to fully understand how neighborhood SES contributes to obesity, it is without question that individuals in socially disadvantaged neighborhoods face more barriers to health than their wealthier counterparts. This study also calls into question the relationship between walkability and changes in BMI and emphasizes the necessity of longitudinal data rather than relying on cross-sectional research.

Application of a social cognitive model in explaining physical activity in Iranian female adolescents.

Adolescent Iranian girls are at high risk for physical inactivity due to cultural barriers such as restrictions regarding exercising in public and research is needed to explore ethnic and gender-related factors associated with physical activity (PA) participation. Using social cognitive theory as the guiding model, the purpose of this study was to test the fit and strength of barriers self-efficacy, outcome expectations, self-regulation and social support in explaining PA in female Iranian adolescents (n = 558). Using path analysis, social support was modeled as an antecedent of self-efficacy and outcome expectations, while self-efficacy was modeled as an antecedent of outcome expectations, self-regulatory planning and PA. Outcome expectations and self-regulatory planning were subsequently modeled as additional antecedents of PA. The model explained 52% of the variance in PA. The two significant (P < 0.05) direct effects were from self-efficacy and outcome expectations. Social support from mothers, fathers and friends had significant indirect effects on PA through self-efficacy. These results will allow for future research and interventions not only for female Iranian adolescents but also for similar cultural and immigrant groups that have been neglected to date in the PA literature.

Search for maximal flavor violating scalars in same-charge lepton pairs in pp collisions at sqrt[s]=1.96 TeV.

Models of maximal flavor violation (MxFV) in elementary particle physics may contain at least one new scalar SU(2) doublet field Phi(FV)=(eta(0),eta(+)) that couples the first and third generation quarks (q_(1), q_(3)) via a Lagrangian term L(FV)=xi(13)Phi(FV)q(1)q(3). These models have a distinctive signature of same-charge top-quark pairs and evade flavor-changing limits from meson mixing measurements. Data corresponding to 2 fb(-1) collected by the Collider Dectector at Fermilab II detector in pp[over ] collisions at sqrt[s]=1.96 TeV are analyzed for evidence of the MxFV signature. For a neutral scalar eta(0) with m_(eta;(0))=200 GeV/c(2) and coupling xi(13)=1, approximately 11 signal events are expected over a background of 2.1+/-1.8 events. Three events are observed in the data, consistent with background expectations, and limits are set on the coupling xi(13) for m(eta(0)=180-300 GeV/c(2).

Application of the health promotion model to predict stages of exercise behaviour in Iranian adolescents.

A cluster random sample of 1073 students in the Islamic Republic of Iran (mean age 14.37 years) completed a self-report questionnaire consisting of an exercise measure, selected constructs of Pender's health promotion model and an assessment of stages of behaviour change in exercise. In multivariate discriminant analysis, exercise self-efficacy, perceived barriers to exercise, perceived benefits of exercise and exercise behaviour were significant predictors of the stage of exercise behaviour change for both female and male adolescents. The findings support the importance of self-efficacy for engaging in physical activity for both sexes of Iranian adolescents. The barriers faced by Iranian girls should be considered in interventions to increase physical activity rates.

Application of the health promotion model to predict stages of exercise behaviour in Iranian adolescents

A cluster random sample of 1073 students in the Islamic Republic of Iran [mean age 14.37 years] completed a self-report questionnaire consisting of an exercise measure, selected constructs of Pender's health promotion model and an assessment of stages of behaviour change in exercise. In multivariate discriminant analysis, exercise self-efficacy, perceived barriers to exercise, perceived benefits of exercise and exercise behaviour were significant predictors of the stage of exercise behaviour change for both female and male adolescents. The findings support the importance of self-efficacy for engaging in physical activity for both sexes of Iranian adolescents. The barriers faced by Iranian girls should be considered in interventions to increase physical activity rates