The current issue of the Journal of Public Health highlights different aspects and determinants of health, prevention and health care planning in various countries around the world. Socio-economic factors and lifestyle differences effecting health, as well as population health and health in specific groups are explored thoroughly in the presented studies. The described results help to identify starting points to reduce health-related risk factors for example in the younger age-groups of populations as well as to meet challenges associated with the demographic change and the resultant higher number of elderly people. The guiding principle behind the studies is not just to improve health at the individual level but at the same time to improve the health status of entire populations. Although the health problems differ between countries, the role and importance of public health is universal: to provide information to help to create better living conditions and health care provisions and to improve the knowledge for a more successful promotion of healthy behaviour.

One group of the studies addresses the problem of overweight and obesity as well as its associated consequences in children and adolescents and explores possible interventions. The study of Ali et al. investigated the influence of sports participation in contrast to alcohol consumption on popularity of overweight adolescents of different races and ethnicities in the United States. Lätt et al. examined the associations between physical activity, cardiovascular fitness and body fatness estimators in boys in Estonia. Furthermore, they assessed whether the weight status (normal weight/overweight or obese) influenced these associations.

Mathiesen et al. analysed, in a general population-based sample in Norway, alcohol use patterns to identify socio-demographic groups with a higher risk for hazardous and harmful alcohol consumption which should be focused on by specific prevention strategies. Asgary et al. investigated the prevalence of hypertension and pre-hypertension as well as the associated risk factors and the awareness about high blood pressure values in a remote farming community in India. The results revealed a high age-adjusted blood pressure rate comparable to the United States and a very low awareness of hypertension among the studied population. Liu et al. took a closer look at the associations of cigarette smoking with body mass index (BMI) and other body fatness indicators (e.g. waist circumference) in Chinese male adults in order to achieve a more differentiated understanding of the relations between smoking and smoking cessation and body weight.

Two further studies investigated the determinants of anaemia in two different countries. The study of Jalambo et al. determined the prevalence of anaemia among female secondary students in the Gaza Strip and assessed the risk factors that are relevant for the development of anaemia. Singh analysed the effect of lifestyle behaviours on women’s anaemia level to understand better the high prevalence of anaemia in India. The results showed that lifestyle variables play a significant role in causing anaemia.

Finally, our study (Siewert et al.) addressed the ageing of populations and resulting health care consequences that are an issue in many industrialised countries. We projected the future outpatient health-care utilisation in a region with a pronounced demographic change in the north-eastern part of Germany. The results can be used as a basis for future medical care planning.

The methods of data collection applied in the presented studies range from anthropometric and medical measures to interviews and self-administered questionnaires in random samples that represent the general population or population groups of special interest. The results underline the importance of cross-sectional and longitudinal studies based on survey data that are collected specifically to evaluate the health status of populations and the factors impairing or improving health and determining the need for medical care. Such differentiated and informative results taking into account all kinds of patient-related characteristics, risk factors, behaviours and beliefs, culture, and system determinants such as access to medical care, could not have been achieved based on reimbursement or other secondary data alone, for example medical records or health insurance data. This again underlines the importance of field studies yielding primary epidemiologic data for state of the art descriptive and analytic epidemiology of health care research.

And last but not least, two additional articles reveal important insights concerning the evaluation of preventive or interventional measures. Dadaczynski and de Vries conducted a review to identify indicators of the quality of school-based programmes targeting healthy eating and physical activity, while Porzsolt et al. demonstrated that pragmatic trials are of high importance for public health research because they investigate whether the efficacy found in randomized controlled trials under ideal conditions really extends to real world conditions. Effectiveness research is important to show which interventions are actually applied in real life practice and which outcomes are generated in day-to-day health care.