Environmental health indicators in policy evaluation

In carrying out two projects involving environmental health indicators - a national environmental health programme evaluation and an international environmental health indicator system - in parallel, it became apparent that an international indicator set has limitations regarding the evaluation of a national programme such as the Swiss National Environment and Health Action Plan (NEHAP). The international indicator set proposed by WHO serves the structured description of the underlying cause-effect chains, allows an integrated monitoring of the general environment and health situation and provides valuable international comparisons. However, the relevance of an international indicator set varies in the national context. Moreover, it does not allow the evaluation of a national implementation process, which is highly important in assessing success or failure of an environmental health promotion programme. For a comprehensive evaluation of such a programme, a specific evaluation concept derived from the formulated goals and targets needs to be developed with emphasis on evaluation of the implementation proces

The first years of implementation of the Swiss National Environment and Health Action Plan (NEHAP): Lessons for environmental health promotion

Summary: The National Environment and Health Action Plans (NEHAPs) are a novel attempt to integrate environmental protection and health promotion in political programmes. Throughout Europe, about 40 NEHAPs have been developed so far. The Swiss NEHAP was among the first to be developed in an industrialised country. We discuss strength and weaknesses of the Swiss NEHAP and draw first conclusions on the development and implementation process of such programmes, illustrated by examples of other European NEHAPs. The strengths of the Swiss NEHAP lie in the formulation of specific targets in selected areas, its approach as a environmental health promotion programme, and its comprehensive evaluation. Weaknesses in most NEHAPs are the lack of involvement of the general public and of the economic sector, and the absence of an implementation strategy along with adequate financin

Is the ebb of asthma due to the decline of allergic asthma? A prospective consultation-based study by the Swiss Sentinel Surveillance Network, 1999-2005

Objective. There are conflicting views on time trends of asthma and atopy during the last 10-15 years. Additional confusion is caused by the term of asthma which is a unifying name for different phenotypes. Asthma has been a topic for investigation to the Swiss Sentinel Surveillance Network (SSSN) since 1989. The objective of the actual study was to determine the influence of the allergic and non-allergic components of asthma on time trends from 1999 to 2005. Methods. Primary care physicians participating in the SSSN were guided by diagnostic criteria for asthma. Rates of asthma episodes per 1000 consultations were calculated for all, for first and subsequent asthma episodes and for allergic and non-allergic asthma. Allergic asthma was defined as asthmatic manifestations in conjunction with eczema and/or hay fever. The smoothed time trend and its 95% confidence intervals were determined using generalized additive models with a loess smoother adjusting for seasonality. Results. Consultations for allergic asthma have decreased between 1999 and 2005. Looking at different age groups, asthma associated with hay fever was reported with decreasing frequency in all age groups, whereas when associated with eczema, the other used marker of allergic asthma, slightly increased among young children. Conclusions. The decrease of consultations for asthma is most probably due to the allergic component of asthma. Diagnostic shift over time and ready available medications probably contributed to this phenomenon. Our findings indicate a real decline of allergic asthma. Practice recommendations. Consultations for asthma have decreased over recent years. The decrease of consultations for asthma is most probably due to the allergic component of asthma. Diagnostic shift over time and available medications probably contributed to this phenomenon. Strength of Recommendation Taxonomy (SORT) rating: strength of recommendation = C, level of evidence = 

Physical activity and health – what are the recommendations and where do we find the Swiss population?

Since 1999 Switzerland has physical activity recommendations for adults, since 2006 also for school-age children and adolescents. The best available estimates indicate that 32% of adults meet the recommendations for three endurance-type training sessions and another 9% the minimal recommendations of half an hour moderate intensity physical activity on most days of the week. 13% of Swiss adolescents seem to meet the minimal recommendations of one hour on every day of the week, 35% on five days per week. These data rely on standardised, nationally representative surveys providing robust estimates, but they are based on self-report instruments of untested, poor or questionable validity against objective measurements of physical activity. No nationally representative data is available on compliance of children with the recommendations. Physical activity recommendations for all age groups in Switzerland should be reviewed in the light of the WHO recommendations expected for 2010. Established national surveys should be continued to allow the description of trends. In addition, physical activity behaviour of children and other age groups should be assessed using internationally standardised and nationally validated questionnaires and objective measurements. The feasibility of physiological measurements at the population level should be explored

Years of life lost attributable to air pollution in Switzerland: dynamic exposure-response model

Background There is debate on how the effect of air pollution should be assessed. We propose an approach to estimate its impact on adult and infant mortality that integrates data from long-term epidemiological studies and studies of interventions to reduce pollution. We use the method to estimate the number of years of life lost (YLLs) attributable to air pollution during 1 year in Switzerland. Methods A dynamic exposure-response model was implemented, which uses an exponential function (exp−kt) to model the change in mortality after cessation of air pollution. The model was populated with relative risk estimates and estimates of time constant k from the literature. Air pollution exposure in Switzerland was modelled using data from emission inventories. YLLs attributable to air pollution were calculated by taking the difference between observed survival probabilities in Switzerland in 2000 and modified survival probabilities, assuming no air pollution during the year 2000. Results Meta-analyses of three studies of adult mortality and five studies of infant mortality gave relative risks of 1.059 (95% confidence interval (CI) 1.031-1.088) and 1.056 (95% CI 1.026-1.088) per 10 μg/m3 increase in PM10 concentration. Time constants k derived from two studies of the effects of the closing down of a steel mill in the Utah Valley and of the coal ban in Dublin were 0.88 and 0.11. Assuming a time constant k of 0.5 resulted in 42 400 (95% CI 22 600-63 600) YLLs, with 4.0% being ascribed to infant deaths. A total of 39% of the effect occurred in the same year and 80% within 5 years. The estimated number of YLLs was little affected by the choice of the time constant. Conclusions In contrast to traditional steady-state models the dynamic model allows changes in mortality following short-term increases or decreases in air pollution levels to be quantified. This type of information is of obvious interest to policy maker

Trend in active transportation to school among Swiss school children and its associated factors: three cross-sectional surveys 1994, 2000 and 2005

BACKGROUND: Giving the rising trend in childhood obesity in many countries including Switzerland, strategies to increase physical activity such as promoting active school travel are important. Yet, little is known about time trends of active commuting in Swiss schoolchildren and factors associated with changes in walking and biking to school. METHODS: Between 1994 and 2005, information about mobility behaviour of children aged 6-14 years was collected within three Swiss population based national travel behaviour surveys. Mode of transport to school was reported for 4244 children. Weighted multivariate logistic regression analyses were used to assess active school travel time trends and their influencing factors. RESULTS: More than 70% of Swiss children walked or biked to school. Nevertheless, the proportion of children biking to school decreased (p = 0.05, linear trend), predominately in urban areas, and motorized transportation increased since 1994 (p = 0.02). Distance to school did not change significantly over time but availability of bikes decreased (p < 0.001) and number of cars per household increased (p < 0.001). The association between survey year and bike use was significantly modified by living in an urban area (OR (95%CI): 1.0, 0.63 (0.44-0.90), 0.71 (0.49-1.03), respectively for 1994, 2000 and 2005) and by distance to school (OR (95%CI): 1.0, 0.65 (0.40-1.05), 0.50 (0.23-0.79) for the same years and for children who lived more than a mile away from school). CONCLUSIONS: Programs to encourage safe biking and to limit car use as mode of transport to school are warranted to stop this tren

Assessment of intensity, prevalence and duration of everyday activities in Swiss school children: a cross-sectional analysis of accelerometer and diary data

BACKGROUND: Appropriately measuring habitual physical activity (PA) in children is a major challenge. Questionnaires and accelerometers are the most widely used instruments but both have well-known limitations. The aims of this study were to determine activity type/mode and to quantify intensity and duration of children's everyday PA by combining information of a time activity diary with accelerometer measurements and to assess differences by gender and age. METHODS: School children (n = 189) aged 6/7 years, 9/10 years and 13/14 years wore accelerometers during one week in winter 2004 and one in summer 2005. Simultaneously, they completed a newly developed time-activity diary during 4 days per week recording different activities performed during each 15 min interval. For each specific activity, the mean intensity (accelerometer counts/min), mean duration per day (min/d) and proportion of involved children were calculated using linear regression models. RESULTS: For the full range of activities, boys accumulated more mean counts/min than girls. Adolescents spent more time in high intensity sports activities than younger children (p < 0.001) but this increase was compensated by a reduction in time spent playing vigorously (p = 0.04). In addition, adolescents spent significantly more time in sedentary activities (p < 0.001) and accumulated less counts/min during these activities than younger children (p = 0.007). Among moderate to vigorous activities, children spent most time with vigorous play (43 min/day) and active transportation (56 min/day). CONCLUSION: The combination of accelerometers and time activity diaries provides insight into age and gender related differences in PA. This information is warranted to efficiently guide and evaluate PA promotion