Reducing social inequalities in smoking: can evidence inform policy? A pilot study

Objective: To assess the potential contribution of evidence from existing systematic reviews of effectiveness to answering the question: what works in reducing social inequalities in smoking? Data source: The Cochrane Library (2002/4). Study selection: Systematic reviews of the effectiveness of community based tobacco control interventions, and all the primary studies included in one of these reviews. Data extraction: Reviews and primary studies were assessed for intent to assess the social distribution of intervention effects, information about the social inclusiveness or targeting of interventions, baseline sociodemographic data collected on participants, and estimates of effect size stratified by sociodemographic variables. Data synthesis: Only one review aimed to examine outcomes stratified by sex, age or socioeconomic status, and these aims were only achieved with respect to sex. Sociodemographic data about participants were frequently collected in primary studies, but not used to compare intervention effects between social groups. Conclusions: There may be scope for using existing research more effectively to contribute to evidence based policy to reduce social inequalities in smoking—by explicitly seeking stratified outcome data in new systematic reviews, by re-analysing original datasets, and/or by meta-analysis of individual participant data

Systematic reviews of health effects of social interventions: 1. Finding the evidence: how far should you go?

Study objective: There is little guidance on how to identify useful evidence about the health effects of social interventions. The aim of this study was to assess the value of different ways of finding this type of information. Design: Retrospective analysis of the sources of studies for one systematic review. Setting: Case study of a systematic review of the effectiveness of interventions in promoting a population shift from using cars towards walking and cycling. Main results: Only four of the 69 relevant studies were found in a "first-line" health database such as Medline. About half of all relevant studies were found through the specialist Transport database. Nine relevant studies were found through purposive internet searches and seven relevant studies were found by chance. The unique contribution of experts was not to identify additional studies, but to provide more information about those already found in the literature. Conclusions: Most of the evidence needed for this review was not found in studies indexed in familiar literature databases. Applying a sensitive search strategy across multiple databases and interfaces is very labour intensive. Retrospective analysis suggests that a more efficient method might have been to search a few key resources, then to ask authors and experts directly for the most robust reports of studies identified. However, internet publications and serendipitous discoveries did make a significant contribution to the total set of relevant evidence. Undertaking a comprehensive search may provide unique evidence and insights that would not be obtained using a more focused search

Promoting walking and cycling as an alternative to using cars: systematic review

Objectives: To assess what interventions are effective in promoting a population shift from using cars towards walking and cycling, and to assess the health and distributional effects of such interventions. Data sources: Published and unpublished reports in any language identified from electronic databases, bibliographies, websites and reference lists. Review methods: Systematic search and appraisal to identify experimental or observational studies with a prospective or controlled retrospective design that evaluated any intervention applied to an urban population or area by measuring outcomes in members of the local population. Results: 22 studies met the inclusion criteria. We found some evidence that targeted behaviour change programmes can change the behaviour of motivated subgroups, resulting (in the largest study) in a modal shift of around 5% of all trips at a population level. Single studies of commuter subsidies and a new railwy station have also shown modest effects. The balance of best available evidence about publicity campaigns, engineering measures and other interventions suggests that they have not been effective. Participants in trials of active commuting experienced short-term improvements in certain health and fitness measures, but we found no good evidence about the health effects of any effective population-level intervention. Conclusions: The best available evidence of effectiveness is for targeted behaviour change programmes, but the social distribution of their effects is unclear and some other types of intervention remain to be rigorously evaluated. We need a stronger evidence base for the health impacts of transport policies, preferably based on properly conducted prospective studies

Systematic reviews of health effects of social interventions: 2. Best available evidence: how low should you go?

Study objective: There is little guidance on how to select the best available evidence of health effects of social interventions. The aim of this paper was to assess the implications of setting particular inclusion criteria for evidence synthesis. Design: Analysis of all relevant studies for one systematic review, followed by sensitivity analysis of the effects of selecting studies based on a two dimensional hierarchy of study design and study population. Setting: Case study of a systematic review of the effectiveness of interventions in promoting a population shift from using cars towards walking and cycling. Main results: The distribution of available evidence was skewed. Population level interventions were less likely than individual level interventions to have been studied using the most rigorous study designs; nearly all of the population level evidence would have been missed if only randomised controlled trials had been included. Examining the studies that were excluded did not change the overall conclusions about effectiveness, but did identify additional categories of intervention such as health walks and parking charges that merit further research, and provided evidence to challenge assumptions about the actual effects of progressive urban transport policies. Conclusions: Unthinking adherence to a hierarchy of study design as a means of selecting studies may reduce the value of evidence synthesis and reinforce an "inverse evidence law" whereby the least is known about the effects of interventions most likely to influence whole populations. Producing generalisable estimates of effect sizes is only one possible objective of evidence synthesis. Mapping the available evidence and uncertainty about effects may also be important

Perceived characteristics of the environment associated with active travel: development and testing of a new scale

Background Environmental characteristics may be associated with patterns of physical activity. However, the development of instruments to measure perceived characteristics of the local environment is still at a comparatively early stage, and published instruments are not necessarily suitable for application in all settings. We therefore developed and established the test-retest reliability of a new scale for use in a study of the correlates of active travel and overall physical activity in deprived urban neighbourhoods in Glasgow, Scotland. Methods We developed and piloted a 14-item scale based on seven constructs identified from the literature (aesthetics, green space, access to amenities, convenience of routes, traffic, road safety and personal safety). We administered the scale to all participants in a random postal survey (n = 1322) and readministered the scale to a subset of original respondents (n = 125) six months later. We used principal components analysis and Varimax rotation to identify three principal components (factors) and derived summary scores for subscales based on these factors. We examined the internal consistency of these subscales using Cronbach's alpha and examined the test-retest reliability of the individual items, the subscale summary scores and an overall summary neighbourhood score using a combination of correlation coefficients and Cohen's kappa with and without weighting. Results Public transport and proximity to shops were the items most likely to be rated positively, whereas traffic volume, traffic noise and road safety for cyclists were most likely to be rated negatively. Three principal components – 'safe and pleasant surroundings', 'low traffic' and 'convenience for walking' – together explained 45% of the total variance. The test-retest reliability of individual items was comparable with that of items in other published scales (intraclass correlation coefficients (ICCs) 0.34–0.70; weighted Cohen's kappa 0.24–0.59). The overall summary neighbourhood score had acceptable internal consistency (Cronbach's alpha 0.72) and test-retest reliability (ICC 0.73). Conclusion This new scale contributes to the development of a growing set of tools for investigating the role of perceived environmental characteristics in explaining or mediating patterns of active travel and physical activity

Evaluating health effects of transport interventions: methodologic case study

Background: There is little evidence about the effects of environmental interventions on population levels of physical activity. Major transport projects may promote or discourage physical activity in the form of walking and cycling, but researching the health effects of such “natural experiments” in transport policy or infrastructure is challenging. Methods: Case study of attempts in 2004–2005 to evaluate the effects of two major transport projects in Scotland: an urban congestion charging scheme in Edinburgh, and a new urban motorway (freeway) in Glasgow. Results: These interventions are typical of many major transport projects. They are unique to their context. They cannot easily be separated from the other components of the wider policies within which they occur. When, where, and how they are implemented are political decisions over which researchers have no control. Baseline data collection required for longitudinal studies may need to be planned before the intervention is certain to take place. There is no simple way of defining a population or area exposed to the intervention or of defining control groups. Changes in quantitative measures of health-related behavior may be difficult to detect. Conclusions: Major transport projects have clear potential to influence population health, but it is difficult to define the interventions, categorize exposure, or measure outcomes in ways that are likely to be seen as credible in the field of public health intervention research. A final study design is proposed in which multiple methods and spatial levels of analysis are combined in a longitudinal quasi-experimental study

Comment on "Are periodic solar wind number density structures formed in the solar corona?" by N. M. Viall et al., 2009, Geophys. Res. Lett., 36, L23102, doi:10.1029/2009GL041191

Location of formation of periodic solar wind number density structures is discussed. Observation of proton and alpha anticorrelation in these structures [Viall et al., 2009] indicates that taking into account that bulk velocity of aplha-particles is higher than that of proton the place of formation for these structures should be located at distance less 0.002 AU from place of observation.Comment: 6 pages, submitted in GR

Use and cumulation of evidence from modelling studies to inform policy on food taxes and subsidies: biting off more than we can chew?

Abstract Background Food tax-subsidy policies are proposed to hold promise for helping to produce healthier patterns of food purchasing and consumption at population level. Evidence for their effects derives largely from simulation studies that explore the potential effects of untried policies using a mathematical modelling framework. This paper provides a critique first of the nature of the evidence derived from such simulation studies, and second of the challenges of cumulating that evidence to inform public health policy. Discussion Effects estimated by simulation studies of food taxes and subsidies can be expected to diverge in potentially important ways from those that would accrue in practice because these models are simplified, typically static, representations of complex adaptive systems. The level of confidence that can be placed in modelled estimates of effects is correspondingly low, and the level of associated uncertainty is high. Moreover, evidence from food tax-subsidy simulation studies cannot meaningfully be cumulated using currently available quantitative evidence synthesis methods, to reduce uncertainty about effects. Summary Simulation studies are critical for the initial phases of an incremental research process, for drawing together diverse evidence and exploring potential longer-term effects. While simulation studies of food taxes and subsidies provide a valuable and necessary input to the formulation of public health policy in this area, they are unlikely to be sufficient, and policy makers should not place excessive reliance on evidence from such studies, either singly or cumulatively. To reflect known and unknown limitations of the models, results of such studies should be interpreted cautiously as tentative projections. Modelling studies should increasingly be integrated with more empirical studies of the effects of food tax and subsidy policies in practice

Improving techniques for the WaxTag® possum (Trichosurus vulpecula) monitoring index

To manage brushtail possums (Trichosurus vulpecula) accurate estimates of abundance are essential. Direct counts are not feasible for large populations and index techniques are normally employed. A new index technique for estimating possum abundance is the WaxTag®. They are potentially more effective than traps because they are small, easier to use, very lightweight and, therefore, higher numbers can be set out in the field. Whilst a national monitoring protocol for WaxTag®s has been developed, it is important to determine whether improvements can be made. This study investigated firstly whether luminescent-coloured WaxTag®s were more attractive than the WaxTag® with a ‘flour blaze’ and, secondly, whether raising the WaxTag®s 700 mm above the ground reduced detectability. Possums significantly preferred the flour blaze over luminescence and raising WaxTag®s did not significantly reduce detectability. Accordingly, WaxTag®s could be raised up above ground-dwelling non-target species without reducing statistical precision

The climate emergency across business, community and campaign groups: motivations and barriers to driving change for the common good

Initiatives to help tackle the climate emergency have tended to focus on large-scale actions that governments can take and smaller-scale actions for individuals, with relatively limited attention given to the mass of groups that form society between these two ends of the spectrum. The aim here is to help close that gap and the chosen areas of study are business, community, and campaign groups. The approach was to assess the existing literature and to conduct three focus groups to identify what motivates these groups to take actions on climate change, while also uncovering the barriers that may drive choices of inaction. The findings indicate that multiple factors motivate environmental engagements across business, community, and campaign groups, but personal ethics and concern for the future play the most vital roles. The most common barriers cited were difficulties in accessing support schemes, a lack of clear accessible information, and financial implications. Better networking and knowledge exchange are considered essential for meaningful progress. This research provides a new framework, upon which many organisations can be better motivated to take actions in helping deal with the global climate emergency facing humanity. Practical action guides may be developed from existing materials, and small taskforces could be trained to provide direct hands-on support to groups across society, especially those in SMEs and local communities. The energies of younger people and campaigners, combined with the experiences of other generations, would create a powerful force for good