joint strategic needs assessment foundation profile - JSNA

Interative Hull Atlas: www.hullpublichealth.org/Pages/hull_atlas.htm More information: www.jsnaonline.org and www.hullpublichealth.org
Table 407: Public Health Observatory synthetic lifestyle prevalence estimates for Hull
compared to estimates from local health and lifestyle surveys
Estimate
type
Time period / survey Prevalence estimate in Hull (%)*
Smoking Binge
drink
Healthy
eating
Physically
active
Obese
2003-2005 (used in
40.9 26.2 20.0 12.2 27.3
Synthetic 2009 profiles)
2006-2008 (latest) 32.5 28.1 ** ** **
Health & Lifestyle
31.7 21.9 23.0 26.3 20.8
Survey 2007
From
Prevalence Survey
local
35.1 19.9 26.1 30.8 24.4
2009
surveys
Social Capital Survey
32.7 ** 28.1 39.2 26.3
2009
*These „terms‟ are not defined, so it is difficult to know exactly what is meant by „physically
active‟ or „healthy eating‟. Locally, „healthy eating‟ is defined as eating 5-A-DAY, and exercise
was defined based on fulfilling the national exercise recommendations. So definitions may not
be comparable.
**Not published or not asked in local survey.
12.2 Confounding and Effect Modification
Confounding occurs when another factor (or factors) influences the association of
interest. This occurs when this other factor is associated with both the risk factor of
interest and the outcome of interest. For example, if examining the association between
alcohol consumption and lung cancer mortality, it might be that an association is found.
However, smoking is a confounder. There is an association between smoking and
alcohol consumption (see Alcohol report from local adult Health and Lifestyle Survey at
www.hullpublichealth.org). There is also an association between smoking and lung
cancer mortality. Therefore, it is possible that there is no real association between
alcohol consumption and lung cancer mortality. Smoking is acting as a confounder.
Failure to take into account or consider smoking when examining this association can
lead to confounding bias, and reporting an association or relationship between two
factors which are not really related (or related to a lesser extent), but only indirectly
through a third factor which was not considered in the analysis.
Age, gender and deprivation are frequently related to the prevalence of behavioural risk
factors, and poor health and mortality are also associated with age, gender and
deprivation. Therefore, any of these factors can act as confounders when examining the
relationship between risk factors and poor health.
It is also possible that one factor modifies the effect of one factor on another (effect
modification). For example, it could be that there is a strong association between two
factors at younger ages, but at older ages the association could disappear. Age is
modifying the association between the two factors of interest.
Joint Strategic Needs Assessment Foundation Profile – Hull Health Profile: Release 3. March 2011. 772