Ambient polycyclic aromatic hydrocarbon exposure and breast cancer risk in a population-based Canadian case-control study.

PURPOSE: Polycyclic aromatic hydrocarbons (PAHs) represent a class of ubiquitous pollutants recognized as established human carcinogens and endocrine-disrupting chemicals. PAHs have seldom been modeled at the population-level in epidemiological studies. Fluoranthene is a prevalent PAH in urban settings and correlates with the occurrence of other PAHs. The purpose of this study was to evaluate associations between long-term residential exposure to ambient PAHs and breast cancer risk, both pre- and post-menopausal, in Canada. METHODS: Using the National Enhanced Cancer Surveillance System (NECSS), a national-scale Canadian population-based case-control study, annual fluoranthene exposures were estimated using the GEM-MACH-PAH chemical transport model on the basis of geocoded residential histories throughout a 20-year exposure window. Odds ratios (ORs) and 95% confidence intervals (CIs) controlling for potential confounders were estimated using logistic regression. Separate analyses were conducted for Ontario and national samples given a finer-resolution exposure surface and additional risk factor information available for Ontario. RESULTS: Positive associations were observed between fluoranthene exposure and premenopausal breast cancer, with inconsistent findings for postmenopausal breast cancer. For premenopausal breast cancer, adjusted ORs of 2.48 (95% CI: 1.29, 4.77) and 1.59 (95% CI: 1.11, 2.29) were observed when comparing the second highest category of exposure to the lowest, among the Ontario and national samples, respectively. For postmenopausal breast cancer, adjusted ORs were 1.10 (95% CI: 0.67, 1.80) and 1.33 (95% CI: 1.02, 1.73). Associations for the highest level of exposure, across both samples and menopausal strata, were non-significant. CONCLUSION: This study provides support for the hypothesis that ambient PAH exposures increase the risk of premenopausal breast cancer.

Treatment Effect of Zoledronic Acid in Chronic Non-bacterial Osteomyelitis of the Jaw: A Case Series.

Chronic non-bacterial osteomyelitis (CNO) is an autoinflammatory, osteolytic bone disorder sometimes localized to a unifocal site in the jaw, causing long-term pain and reduced function. The aim of this study was to describe the patients with CNO of the jaw, focusing on treatment with zoledronic acid for pain relief. An analysis of medical records of 24 patients with CNO of the jaw, including treatment with zoledronic acid and effects on pain relief. Descriptive statistics and nonparametric tests were used to describe the population and compare treatment effects, respectively. The average treatment period was 33.4 months (median 23; Q1 11.5; Q3 42.0) with an average of 4.1 infusions (median 3; Q1 2; Q3 5) of zoledronic acid. The average pain VAS score (visual analogue scale) was significantly reduced from 7.7 (median 8; Q1 6.5; Q3 8.5) to 2.5 points (median 2; Q1 0.5; Q3 4.5) (p < 0.001). At final visit, 46% of patients reported no pain and 38% reported a reduction of pain. At least 67% of patients had at least one episode of pain recurrence, and most patients experienced the first recurrence within a year of initial treatment. Four patients (16%) had no pain relief from the treatment. In this group of patients with CNO of the jaw, there was a positive response to treatment with zoledronic acid on pain relief, averaging 5.2 points on a pain VAS score, with 84% of patients treated experiencing either a partial or a total reduction in pain after about 2.5 years.

A qualitative review of social media sharing and the 2022 monkeypox outbreak: did early labelling help to curb misinformation or fuel the fire?

BACKGROUND: Misinformation, defined as a claim that is false or misleading, considers information that is both shared with the intention of causing harm, and information that is false with no ill intent. Early attempts to downplay the risk of monkeypox (mpox) by singling out men who have sex with men (MSM) may have had the ill effect of stigmatising this group in discussions online. The aim of this study was to evaluate themes present on Instagram related to the 2022 mpox outbreak under #monkeypox. Specifically, this study sought to determine if the pervasive narratives surrounding the coronavirus disease 2019 (COVID-19) pandemic, particularly related to government mistrust and conspiracy, were penetrating discussions about mpox. METHODS: A total of 255 posts under #monkeypox (the top 85 posts per day, every 10days in July 2022) were collected on Instagram. A content analysis approach, which seeks to quantify themes present, was utilised to evaluate themes present in posts under #monkeypox. RESULTS: Contrary to previous research investigating public health misinformation online, the majority of posts under #monkeypox were categorised as accurate information (85.9%). Moreover, a surprising number of posts were classified as anti-misinformation (32.9%), whereby users actively worked to debunk false information being shared online related to mpox. CONCLUSIONS: We hypothesise that early labelling of the disease as one that strictly affects online MSM communities has resulted in the digital community coming together to fact-check and debunk misinformation under #monkeypox on Instagram.

Life goals as a driving force in traumatic brain injury rehabilitation: a longitudinal dyadic perspective.

BACKGROUND: Traumatic brain injury significantly impacts survivors and their families. Rehabilitation following traumatic brain injury is often complex due to the physical, psychological, and socio-economic problems survivors face. Life goals are considered a motivational factor in rehabilitation. OBJECTIVE: The aim was to explore expectations, problems, and strategies for goal setting in survivors of traumatic brain injury and their family caregivers for one-year during rehabilitation. METHODS: A longitudinal qualitative study using dyadic interviews with survivors and family caregivers was carried out at three time points during the first year following traumatic brain injury. Data was analyzed according to Braun and Clarke's thematic analysis. RESULTS: Eight survivors of traumatic brain injury and their family caregivers completed 24 interviews. Three themes and one sub-theme were identified: 1) life goals as a driving force (subtheme: dyadic discrepancies and conflicts); 2) conflicts between specific, measurable, achievable, realistic, and timed (SMART) goals and life goals; and 3) changing perceptions of the impact of impairments.Life goals are important motivation in the rehabilitation process. Health care professionals must integrate life goals and rehabilitation goals (i.e. SMART goals) to decrease barriers and survivor ambivalence about rehabilitation. Involving both survivors and family caregivers in goal setting increases rehabilitation success.

Screening-level assessment of cancer risk associated with ambient air exposure in Aamjiwnaang First Nation.

The manuscript reports findings from a screening-level assessment of cancer risk from outdoor air in Aamjiwnaang First Nation. Ambient air pollution can contribute to cardiovascular/respiratory diseases, and certain types of cancer. Certain communities may be at higher risk to the negative health impacts due to their geographical proximity to pollution sources. Outdoor air concentrations were mapped and the Lifetime Excess Cancer Risks (LECR) associated with long-term exposure to known carcinogens were estimated. LECR results for both benzene and 1,3-butadiene were above one per million. The LECR for benzene was 6.4 per million when the Health Canada slope factor was applied and 12.0 when using the US EPA. For 1,3-butadiene the LECR estimate was 8.8 per million. This work provides a better understanding of environmental exposures and potential associated cancer risks for residents in the Aamjiwnaang community and highlights the need for further air monitoring and a more detailed risk assessment.

Denosumab vs. zoledronic acid treatment in post-menopausal breast cancer: a 2-year prospective observational study.

Adjuvant treatment for post-menopausal women with early breast cancer (BC) includes aromatase inhibitors (AI), known to decrease bone mineral density (BMD). In this study, we investigate whether denosumab is a valid second option for patients unable to receive standard adjuvant i.v. zoledronic acid (ZA). In total, 212 patients have been evaluated after they did not receive ZA. Of those 194 were included. After evaluation by an endocrinologist, all patients were offered ZA as their first choice and 15% accepted (N = 29). The remaining 85% were offered denosumab (N = 165). All patients were followed prospectively with blood tests up to 24 months. DXA scans were performed at baseline and 24 months. No difference was observed between the two treatment groups at baseline, with regard to anthropometry and standard biochemistry. Markers of bone turnover (p-PINP, p-CTX, p-bone-specific alkaline phosphatase and p-osteocalcin) all showed significant suppression compared to baseline and remained suppressed throughout the 2 years. BMD showed small and significant increases at the spine (0.024 g/cm2) and total hip (0.019 g/cm2) in the denosumab group but no change at the femoral neck(-0.011g/cm2). In the ZA group, we observed no significant change at the spine (0.015 g/cm2) and total hip (-0.001g/cm2) and a small significant decrease at the femoral neck (-0.037 g/cm2). However, when we compared BMD change between the treatment groups, we found no significant difference.Conclusions: Our data indicate that for BC patients in AI treatment who refused or were not able to receive ZA treatment, denosumab might be recommended as a second choice. Regarding markers of bone turnover and BMD denosumab is equal to ZA.Summary: Women with early breast cancer receiving anti-estrogen treatment are at risk of developing osteoporosis.We followed 194 women receiving zoledronic acid (ZA) or denosumab for up to 2 years.We find that with regard to bone protection, denosumab is a viable alternative to ZA and might be recommended as a second choice.

Temporal Alignment of Dual Monitor Accelerometry Recordings.

Combining accelerometry from multiple independent activity monitors worn by the same subject have gained widespread interest with the assessment of physical activity behavior. However, a difference in the real time clock accuracy of the activity monitor introduces a substantial temporal misalignment with long duration recordings which is commonly not considered. In this study, a novel method not requiring human interaction is described for the temporal alignment of triaxial acceleration measured with two independent activity monitors and evaluating the performance with the misalignment manually identified. The method was evaluated with free-living recordings using both combined wrist/hip (n = 9) and thigh/hip device (n = 30) wear locations, and descriptive data on initial offset and accumulated day 7 drift in a large-scale population-based study (n = 2513) were calculated. The results from the Bland-Altman analysis show good agreement between the proposed algorithm and the reference suggesting that the described method is valid for reducing the temporal misalignment and thus reduce the measurement error with aggregated data. Applying the algorithm to the n = 2513 samples worn for 7-days suggest a wide and substantial issue with drift over time when each subject wears two independent activity monitors.

Exercise-A Panacea of Metabolic Dysregulation in Cancer: Physiological and Molecular Insights.

Metabolic dysfunction is a comorbidity of many types of cancers. Disruption of glucose metabolism is of concern, as it is associated with higher cancer recurrence rates and reduced survival. Current evidence suggests many health benefits from exercise during and after cancer treatment, yet only a limited number of studies have addressed the effect of exercise on cancer-associated disruption of metabolism. In this review, we draw on studies in cells, rodents, and humans to describe the metabolic dysfunctions observed in cancer and the tissues involved. We discuss how the known effects of acute exercise and exercise training observed in healthy subjects could have a positive outcome on mechanisms in people with cancer, namely: insulin resistance, hyperlipidemia, mitochondrial dysfunction, inflammation, and cachexia. Finally, we compile the current limited knowledge of how exercise corrects metabolic control in cancer and identify unanswered questions for future research.

Demographic, medical, social-cognitive, and environmental correlates of meeting independent and combined physical activity guidelines in kidney cancer survivors.

PURPOSE: Guidelines for cancer survivors recommend both aerobic physical activity (PA) and strength training (ST). Few kidney cancer survivors (KCS) are meeting single-activity or combined guidelines; therefore, examining factors influencing PA participation is warranted. The purpose of this study is to examine demographic, medical, social-cognitive, and environmental correlates of meeting independent (i.e., aerobic-only, strength training (ST)-only) and combined guidelines (i.e., aerobic and ST) in KCS. METHODS: KCS (N = 651) completed self-reported measures of PA and demographic, medical, social-cognitive, and perceived environmental factors. Built environment was assessed using the geographic information systems (GIS). Multinomial logistic regressions were conducted to determine the correlates of meeting the combined versus independent guidelines. RESULTS: Compared with meeting neither guideline, meeting aerobic-only guidelines was associated with higher intentions (p < .01) and planning (p < .01); meeting ST-only guidelines was associated with higher intentions (p = .02) and planning (p < .01), lower perceived behavioral control (PBC) (p = .03), healthy weight (p = .01), and older age (p < .01); and meeting the combined guidelines were associated with higher intentions (p < .01), planning (p = .02), higher instrumental attitudes (p < .01), higher education (p = .04), better health (p < .01), and localized cancer (p = .05). Additionally, compared with neither guideline, meeting aerobic-only (p < .01) and combined (p < .01) guidelines was significantly associated with access to workout attire. Compared with neither guideline, meeting aerobic-only guidelines was associated with proximity to retail (p = .02). CONCLUSION: PA participation correlates may vary based on the modality of interest. Interventions may differ depending on the modality promoted and whether KCS are already meeting single-modality guidelines.

Using geographic information systems to estimate potential pesticide exposure at the population level in Canada.

Residents in close proximity to agricultural land are at risk of higher pesticide exposures. The purpose of this study was to generate national population-level exposure estimates for Canada for three commonly applied pesticides that are suspected carcinogens (2,4-dichlorophenoxyacetic acid (2,4-D), glyphosate and chlorothalonil). Using geographic information systems, pesticide exposure was estimated for every - census subdivision (CSD) in Canada (n = 5054) by combining raster-based surfaces for the distribution of crops with average crop-specific pesticide application rates data. Analyses examined all identified crops in combination with different pesticide application rates to obtain a cumulative potential total exposure. Specifically, the number of acres of particular crops were calculated for each CSD and then multiplied by the average pesticide application rates data, summed across crops, and combined with population data by CSD to provide a potential pesticide exposure estimate for each CSD. Results demonstrate that the population exposure varies greatly depending on agricultural production by CSD region. For example, in Ontario, the 2,4-D application rate was an average of 361 kg/km2, while in Saskatchewan, which primarily grows field/cereal crops, 2,4-D application rates were much higher (3810 kg/km2). The highest potential exposures to all three pesticides were in the prairie provinces (Alberta, Saskatchewan, Manitoba) along with Prince Edward Island, Southern Quebec and British Columbia. This work can be used in conjunction with other exposure assessment approaches to better understand overall pesticide exposure among Canada's general population.

Comparative optimism about infection and recovery from COVID-19; Implications for adherence with lockdown advice.

BACKGROUND: Comparative optimism, the belief that negative events are more likely to happen to others rather than to oneself, is well established in health risk research. It is unknown, however, whether comparative optimism also permeates people's health expectations and potentially behaviour during the COVID-19 pandemic. OBJECTIVES: Data were collected through an international survey (N = 6485) exploring people's thoughts and psychosocial behaviours relating to COVID-19. This paper reports UK data on comparative optimism. In particular, we examine the belief that negative events surrounding risk and recovery from COVID-19 are perceived as more likely to happen to others rather than to oneself. METHODS: Using online snowball sampling through social media, anonymous UK survey data were collected from N = 645 adults during weeks 5-8 of the UK COVID-19 lockdown. The sample was normally distributed in terms of age and reflected the UK ethnic and disability profile. FINDINGS: Respondents demonstrated comparative optimism where they believed that as compared to others of the same age and gender, they were unlikely to experience a range of controllable (eg accidentally infect/ be infected) and uncontrollable (eg need hospitalization/ intensive care treatment if infected) COVID-19-related risks in the short term (P < .001). They were comparatively pessimistic (ie thinking they were more at risk than others for developing COVID-19-related infection or symptoms) when thinking about the next year. DISCUSSION: This is one of the first ever studies to report compelling comparative biases in UK adults' thinking about COVID-19.

Relatives' strategies in subacute brain injury rehabilitation: The warrior, the observer and the hesitant.

BACKGROUND: Relative involvement is crucial in rehabilitation when patients are incapable of being involved due to cognitive and functional dysfunction. However, studies have shown that this is complex because of differing understandings of the meaning of involvement as well as diverse needs to be involved. AIMS AND OBJECTIVES: To explore the experience of the rehabilitation process from the perspectives of relatives of patients with a traumatic brain injury. The aim of the study was, through a theoretical-empirical analysis, to identify relatives' strategies and practices in the rehabilitation process as evidenced in meetings with providers. DESIGN: A longitudinal study with a qualitative approach, drawing on the theory of Pierre Bourdieu. METHODS: Data were generated using participant observation and semi-structured interviews. Participants were eleven relatives of patients with a severe traumatic brain injury, followed through in-patient rehabilitation varying from 9-12 weeks. Analysis was undertaken using both an inductive and deductive approach. FINDINGS: Drawing on Bourdieu's concept of strategy, three relative positions were identified, the warrior, the observer and the hesitant. These positions illustrate how different relative positions and their related dispositions influence the strategies used by relatives of patients with a severe traumatic brain injury evidenced in how they act, participate and relate to both the patient and the providers during the course of rehabilitation. CONCLUSIONS: Acknowledging the relatives' positions during the rehabilitation process enables better understanding and support of the relatives in the rehabilitation process to meet their (and thus the patients') diverse needs. RELEVANCE TO CLINICAL PRACTICE: The findings have practical implications in informing how clinicians meet, interact, communicate and involve relatives of adult patients' with traumatic brain injury in decision-making during rehabilitation.

Protocol for evaluating the impact of a national school policy on physical activity levels in Danish children and adolescents: the PHASAR study - a natural experiment.

BACKGROUND: In 2014 the Danish Government introduced a wide-ranging school reform that applies to all public schools in Denmark. The reform involves changes in several aspects of the school structure and content. In a physical activity promotion perspective, a distinctive feature of the school reform is that it has become mandatory to integrate an average of 45 min of daily physical activity in the regular school day. The overarching objective of the PHASAR study is to evaluate the implementation and effect of this ambitious policy-driven physical activity promotion initiative on physical activity and overweight. This paper describes in detail the study protocol. METHODS: The evaluation is divided into a quantitative effect evaluation and a combined quantitative and qualitative process evaluation. A total of 31 schools are enrolled in the PHASAR study including more than 2,000 school-aged children. Objectively measured physical activity data are obtained in the PHASAR study in 2017/18 and compared to repeated cross sectional data collected in four historical school-based studies from 1998 to 2012. Body mass index data from 2012 to 2018 will be collected from The Child Database, which includes repeated cross-sectional assessments on approximately 100,000 children annually. In the absence of a control group, interrupted time-series analysis will be used to evaluate pre- and post-reform physical activity and body mass index levels and trends. A characterization of the school environment for physical activity promotion on a political, environmental, organizational and individual level and school implementation processes will be conducted to evaluate the implementation process. Data will be collected using interviews, surveys, document analyses and observations. DISCUSSION: The PHASAR study is a rare opportunity to evaluate the effectiveness of a nation-wide policy-driven school-based physical activity promotion initiative. The use of objectively measured pre- and post-reform physical activity and body mass index data combined with a characterization of the school implementation processes for physical activity promotion will provide a comprehensive source to evaluate the school reform. The study findings have the potential to influence national and international policy makers, health professionals and school staff.

Progression from Asthma to Chronic Obstructive Pulmonary Disease. Is Air Pollution a Risk Factor?

RATIONALE: Individuals with asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS), have more rapid decline in lung function, more frequent exacerbations, and poorer quality of life than those with asthma or COPD alone. Air pollution exposure is a known risk factor for asthma and COPD; however, its role in ACOS is not as well understood. OBJECTIVES: To determine if individuals with asthma exposed to higher levels of air pollution have an increased risk of ACOS. METHODS: Individuals who resided in Ontario, Canada, aged 18 years or older in 1996 with incident asthma between 1996 and 2009 who participated in the Canadian Community Health Survey were identified and followed until 2014 to determine the development of ACOS. Data on exposures to fine particulate matter (PM2.5) and ozone (O3) were obtained from fixed monitoring sites. Associations between air pollutants and ACOS were evaluated using Cox regression models. MEASUREMENTS AND MAIN RESULTS: Of the 6,040 adults with incident asthma who completed the Canadian Community Health Survey, 630 were identified as ACOS cases. Compared with those without ACOS, the ACOS population had later onset of asthma, higher proportion of mortality, and more frequent emergency department visits before COPD diagnosis. The adjusted hazard ratios of ACOS and cumulative exposures to PM2.5 (per 10 µg/m(3)) and O3 (per 10 ppb) were 2.78 (95% confidence interval, 1.62-4.78) and 1.31 (95% confidence interval, 0.71-2.39), respectively. CONCLUSIONS: Individuals exposed to higher levels of air pollution had nearly threefold greater odds of developing ACOS. Minimizing exposure to high levels of air pollution may decrease the risk of ACOS.

Cost-effectiveness of a day-camp weight-loss intervention programme for children: Results based on a randomised controlled trial with one-year follow-up.

AIMS: The aim was to analyse the cost-effectiveness of an intensive weight-loss intervention for children compared with a low-intensity intervention. METHODS: One hundred and fifteen overweight children (mean age 12.0 ± 0.4) were randomised to either the camp group (CG) ( N=59) or the standard group (SG) ( N=56). Participants in the CG were offered a six-week day-camp weight-loss programme followed by a family-based supportive programme containing four meetings during the succeeding 46 weeks. Participants in the SG were offered a weekly two-hour exercise session for six weeks. Changes in body mass index (BMI) and BMI z-score 12 months after inclusion were used to compare the effects of the two interventions. Incremental cost-effectiveness ratios (ICER) were estimated from the perspective of a Danish municipality. To achieve the required number of participants, an additional intervention was initiated one year later. RESULTS: In comparison with the SG, the CG changed their mean BMI by -1.2 (95% CI -1.8 to -0.5). Compared with the SG children, the CG children changed their BMI z-score by -0.20 (95% CI -0.35 to -0.05). The ICER per decreased BMI point in the CG compared with the SG was DDK 24,928. CONCLUSIONS: Compared with the SG, the CG showed favourable effects after 12 months. However, the CG was more costly. The results observed in the present study may be helpful in guiding decision makers to take more informed decisions when choosing different types of intervention.

The effect of a multi-component camp-based weight-loss program on children's motor skills and physical fitness: a randomized controlled trial.

BACKGROUND: Many weight-loss programs in children are performed without specific foci on training both physical fitness and motor skills. The aim of this study was to describe the effect of a one-year weight-loss program on children's motor skills and physical fitness. METHODS: Participants included 115 overweight fifth-grade children (12.0 years) randomized into either a Day-Camp Intervention Arm (DCIA), with a subsequent family-based support program or a low-intense Standard Intervention Arm (SIA). Physical fitness was assessed by vertical jump, hand grip strength, and a progressive cardio-respiratory fitness test. Motor skills were assessed by the Movement Assessment Battery for Children - second edition (M-ABC-2), age band 3. RESULTS: Loss to follow-up after 52 weeks was 19 % and 32 % in the DCIA and SIA, respectively. Balance skills were improved post-camp, but not after 52 weeks in children from the DCIA compared to the SIA. Contrary to the expected, children from the SIA improved aiming and catching skills relative to the DCIA children. Overall z-scores of the physical fitness components and cardio-respiratory fitness improved more in children from the DCIA compared to children from the SIA. CONCLUSION: In conclusion, the day-camp intervention led to improvements in physical fitness but not in motor skills compared to the standard intervention. Including both motor skills and physical fitness could advantageously be considered in future immersive intervention programmes. TRIAL REGISTRATION: Clinicaltrials NCT01574352, March 26, 2012 (retrospectively registered).

Effects of a multi-component camp-based intervention on inflammatory markers and adipokines in children: A randomized controlled trial.

OBJECTIVE: To examine the effects of a multi-component camp-based intervention on inflammatory markers and adipokines in children. METHODS: One hundred and fifteen children were recruited in Odense, Denmark (2012-2014). The participants were randomly allocated to either the day camp intervention arm (DCIA) or the standard intervention arm (SIA). The intervention for the DCIA consisted of a 6-week camp-based intervention and a 46-week family-based intervention. The SIA was offered one weekly physical activity session for 6 weeks and one educational meeting. C-reactive protein (CRP), monocyte chemoattractant protein-1 (MCP1), leptin, and adiponectin were measured in serum at baseline, 6 weeks and 52 weeks. RESULTS: In comparison with the SIA, the reductions in CRP (P=0.003) and leptin (p<0.001) were larger in the DCIA at 6 weeks. The intervention effects on leptin were significantly mediated by the changes in body fat mass. No intervention effects on CRP and leptin were seen at 52 weeks. No between-group differences in changes in MCP1 and adiponectin were observed at 6 weeks or 52 weeks. CONCLUSIONS: The 6-week camp intervention resulted in reductions in CRP and leptin. The intervention effects did not persist to 52 weeks. The intervention effect on leptin was explained by changes in body fat mass.

Designing for health in school buildings: between research and practice.

AIM: To investigate the kinds of knowledge practitioners use when planning and designing for health in school buildings. METHODS: Twelve semi-structured qualitative interviews were conducted with architects, teachers and officials to investigate use of knowledge in the making of school buildings. RESULTS: Practitioners drew on many kinds and sources of knowledge, but in particular they made use of concepts, examples or pictures or thought-provoking knowledge. However, the interviews indicate a number of hurdles for efficient knowledge sharing between research and practice: (1) a considerable discrepancy between kinds of knowledge used by practice and knowledge traditionally produced by research; (2) research-knowledge and practice-knowledge form two circuits and the flow from one circuit to the other is weak; (3) practitioners' knowledge was often based on experience and therefore person-dependent. It makes the knowledge vulnerable. CONCLUSIONS: Special attention has to be paid by research to concepts and principles to guide the decision-making in practice. Further is recommended to consider new kinds of collaboration between researchers and practitioners.

Installation of speed humps and pedestrian-motor vehicle collisions in Toronto, Canada: a quasi-experimental study.

BACKGROUND: Evidence related to the effectiveness of speed humps on reducing pedestrian-motor vehicle collisions (PMVC) has been conflicting. The purpose of this study was to determine the association between speed hump installation and changes in PMVC rates in Toronto, Canada. METHODS: Speed humps were mapped along with police-reported pedestrian collisions from 2000-2011 and built environment roadway characteristics. A quasi-experimental study identified collision counts before and after speed hump installation, modeled using repeated measures Poisson regression adjusted for season and roadway characteristics. Stratified analyses were conducted by age group and injury severity. RESULTS: There were 27,827 PMVC, with 1344 collisions along 409 roadways with speed humps. PMVC incidence rates/meters of road/month decreased after installation of speed humps (IRR 0.78 95 % CI 0.66, 0.91). Winter, collector roads (versus local), pre-amalgamated city centre and increased land use mix were associated with more collisions. The association between speed humps and PMVC rates decreased more for children (IRR 0.57, 95 % CI 0.41, 0.79) than for adults (IRR 0.80, 95 % CI 0.68, 0.95). CONCLUSIONS: Speed humps are an easily replicated method of traffic calming which have a significant protective effect on PMVC on the roadways where they are installed, particularly for children. There is a need for an area-wide analysis to determine the effects of the installation of speed humps to ensure that PMVC are not being displaced to surrounding roadways.