Evidence for physical activity guidelines as a public health intervention: efficacy, effectiveness and harm – a critical policy sciences approach.

BACKGROUND: Evidence for the efficacy of physical activity in conferring health benefits is unequivocal, and this has led national governments to produce guideline recommendations for physical activity levels in their populations. AIM: To evaluate how far evidence for the efficacy, effectiveness and comparative effectiveness of current physical activity guideline recommendations as a public health intervention is considered in developing guideline recommendations, including a consideration of the extent to which, in comparison to alternatives, they may result in harm. METHODS: Utilising a critical policy sciences approach, national physical activity guideline recommendations in Australia, the UK and the USA, and those of the World Health Organisation, are examined, along with their stated underlying evidence bases, to analyse what evidence has been considered, how it has been interpreted, for what purpose, and with what outcomes. RESULTS: All current guidelines recommend 150 minutes moderate physical activity per week. However, efficacy evidence shows 60 minutes is sufficient to provide some health benefits. None of the guidelines consider effectiveness evidence nor potential effectiveness. No evidence could be found for the effectiveness of a recommendation of 150 minutes in improving population health, and none of the guidelines consider whether a recommendation at a lower but still sufficient level of efficacy (e.g. 60 minutes) would be a more effective public health intervention. CONCLUSIONS: Evidence considered in drawing up physical activity guidelines relates only to the efficacy of physical activity in conferring health benefits. The lack of effectiveness evidence, the failure to consider potential effectiveness, and related un-evidenced value judgements call into question the claim that the guidelines are evidence-based. Because neither effectiveness nor comparative effectiveness is considered, it is possible that current guidelines of 150 minutes may result in net harm to population health in comparison to the opportunity cost of recommendations at alternative levels

The relationship between alcohol consumption and related harm among young university students

Issue addressed: Research has shown that Australian university students consume alcohol at a higher level than their peers from the general population and are therefore more likely to witness and experience alcohol-related harm. This study measured the prevalence of alcohol consumption among 18–24-year-old university students and the association between alcohol consumption and witnessed and experienced harms. Methods: A random cross-sectional sample of university students aged 18–24 years (n = 2466) was recruited via the University Survey Office and through random intercept at campus market day. All participants completed an online survey that included the Alcohol Use Disorders Identification Test, Alcohol Problems Scale and an additional scale measuring witnessed harm. Results: Principal Components Analysis revealed three factors within the Alcohol Problems Scale; i.e. Criminal and Aggressive Behaviour, Health and Emotional Harms and Sexual Harms. Students who consume alcohol at high-risk levels were significantly more likely to score highly on each factor, 1.6 times more likely to experience harm and 1.1 times more likely to witness harm than students who consume alcohol at low-risk levels. Conclusions: The positive association between alcohol consumption and alcohol-related harm supports previous findings. This study adds previous research through the categorisation of harm into factors

Factors influencing psychological distress during a disease epidemic: Data from Australia's first outbreak of equine influenza

BACKGROUND: In 2007 Australia experienced its first outbreak of highly infectious equine influenza. Government disease control measures were put in place to control, contain, and eradicate the disease; these measures included movement restrictions and quarantining of properties. This study was conducted to assess the psycho-social impacts of this disease, and this paper reports the prevalence of, and factors influencing, psychological distress during this outbreak. METHODS: Data were collected using an online survey, with a link directed to the affected population via a number of industry groups. Psychological distress, as determined by the Kessler 10 Psychological Distress Scale, was the main outcome measure. RESULTS: In total, 2760 people participated in this study. Extremely high levels of non-specific psychological distress were reported by respondents in this study, with 34% reporting high psychological distress (K10 > 22), compared to levels of around 12% in the Australian general population. Analysis, using backward stepwise binary logistic regression analysis, revealed that those living in high risk infection (red) zones (OR = 2.00; 95% CI: 1.57-2.55; p < 0.001) and disease buffer (amber) zones (OR = 1.83; 95% CI: 1.36-2.46; p < 0.001) were at much greater risk of high psychological distress than those living in uninfected (white zones). Although prevalence of high psychological distress was greater in infected EI zones and States, elevated levels of psychological distress were experienced in horse-owners nationally. Statistical analysis indicated that certain groups were more vulnerable to high psychological distress; specifically younger people, and those with lower levels of formal educational qualifications. Respondents whose principal source of income was from horse-related industry were more than twice as likely to have high psychological distress than those whose primary source of income was not linked to horse-related industry (OR = 2.23; 95% CI: 1.82-2.73; p < 0.001). CONCLUSION: Although, methodologically, this study had good internal validity, it has limited generalisability because it was not possible to identify, bound, or sample the target population accurately. However, this study is the first to collect psychological distress data from an affected population during such a disease outbreak and has potential to inform those involved in assessing the potential psychological impacts of human infectious diseases, such as pandemic influenza.13 page(s

Increasing walking among older people: A test of behaviour change techniques using factorial randomised N-of-1 trials

Objective: Evaluations of techniques to promote physical activity usually adopt a randomised controlled trial (RCT). Such designs inform how a technique performs on average but cannot be used for treatment of individuals. Our objective was to conduct the first N-of-1 randomised controlled trials (RCTs) of behaviour change techniques with older people and test the effectiveness of the techniques for increasing walking within individuals. Design: Eight adults aged 60-87 were randomised to a 2 (goal-setting vs. active control) x 2 (self-monitoring vs. active control) factorial RCT over 62 days. The time series data was analysed for each single case using linear regressions. Main outcome measures: Walking was objectively measured using pedometers. Results: Compared to control days, goal-setting increased walking in 4 out of 8 individuals and self-monitoring increased walking in 7 out of 8 individuals. While the probability for self-monitoring to be effective in 7 out of 8 participants was beyond chance (p = 0.03), no intervention effect was significant for individual participants. Two participants had a significant but small linear decrease in walking over time. Conclusion: We demonstrate the utility of N-of-1 trials for advancing scientific enquiry of behaviour change and in practice for increasing older people’s physical activity

Access and quality of parks and associations with obesity: A cross-sectional study.

Public health is increasingly engaging with multi-faceted obesity prevention efforts. Although parks represent key community assets for broader public health, they may not be distributed equitably and associations with obesity are equivocal. We investigated park access and quality relative to deprivation and obesity with individual-level data from the Yorkshire Health Study. Compared to the least deprived areas, the moderately and most deprived areas had a greater park access and park quality in terms of features and amenities. However, parks in the moderately and most deprived areas also had the most safety concerns and incivilities. Although deprivation was associated with obesity, contrary to current policy guidance, both park access and quality appear less important for understanding variations in obesity within this study. Although sub-group analyses by deprivation tertile revealed that low quality park amenities in highly and moderately deprived areas may be important for understanding obesity prevalence, all other associations were non-significant