TABLE 5-4 Types of Observational Evidence and Examples of Their Uses

Type of Evidence

Questions That Could Be Addressed

Specific Applications

Quantitative Surveys, Longitudinal Studies, and Opinion Polls

Based on measurements or self-reports of height and weight, how many people are obese in a given region? (“Why” question)

A cross-sectional sample survey yielding descriptive data on levels of obesity using height and weight indicators


Going forward, do self-reported eating choices change in a group of adolescents exposed to different levels of calorie information at their school cafeterias? (“What” question)

A longitudinal cohort study yielding analytic breakdowns of teens’ eating choices according to menu labeling policies in their respective school cafeterias


Given two or more intervention options, which ones do stakeholders prefer? (“How” question)

A cross-sectional sample survey or poll yielding descriptive data on stakeholder preferences

Analysis of Existing Databases

Based on the health department’s data on a city population, what were the recorded levels of cardiovascular disease related to obesity in 2007? (“Why” question)

A secondary analysis of the correlation or other measure of risk between levels of measured obesity and cardiovascular disease in a selected cross-sectional sample


Based on the health department’s data on a city population, what are the trends in cardiovascular disease and obesity levels from 2005 to 2010? (“Why” question)

A trend analysis comparing data for 2005 and 2010 for the percent of people with cardiovascular disease and the percent of people with obesity


Based on the health department’s data on a city population, what are the past lifestyle correlates of cardiovascular disease in obese and nonobese adults in 2007? (“Why” question)

A retrospective, case-control analysis of the relationship between past lifestyle factors and cardiovascular disease in obese and nonobese adults


Compared with another intervention, what are the costs for implementing and operating a school-based program districtwide, based on data from pilot or single-site studies? (“How” question)

A cost-feasibility analysis using preexisting budget and accounting databases


What combination of factors maximally predicts stakeholder preferences with regard to program participation and use? (“How” question)

A projection analysis using preexisting databases on stakeholder preferences, participation, and program management


What level of sales taxes or excise taxes on sugar-sweetened beverages directly results in decreased consumption of these beverages in a state by 50%? (“What” question)

A modeling study in which data on price elasticity, together with data on patterns of sales and consumption of these beverages, are used to estimate the effective level of taxation to decrease consumer consumption by 50%


Which neighborhoods have the highest rates of childhood obesity, and what other characteristics of these neighborhoods might influence these rates? (“Why” question)

A geographic mapping study in which the locations of food stores and outdoor recreational facilities are plotted by neighborhoods or zones around neighborhoods alongside area data on child obesity prevalence


What would be the potential reach of a policy to require calorie labeling on menus of chain restaurants? (“How” question)

Analysis of administrative data on food retail establishment locations and customer sales for the types of restaurants that would fall under the policy

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