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Healthy Vending Iowa

Evidence Summary

Underlying Logic:  Healthy Vending Iowa is based on the policy and organizational levels of the socio-ecological model.  It also includes a social marketing component with targeted messaging to promote healthy snacking and to motivate employees to choose healthier options.  

Strategies Used:  Healthy Vending Iowa employs three evidence-based strategies for healthy eating: 

Formative Evaluation:  Formative work for Healthy Vending Iowa included a literature review of the vending machine food environment, reliability testing of the NEMS-V, pilot testing of Healthy Vending Iowa tools at worksites, and development of the social marketing component.  Reliability testing of the NEMS-V showed good inter-rater and test-retest reliability.  Healthy Vending Iowa tools were distributed to worksites via a CD for pilot testing.  The testing contributed to improvements in the tools and highlighted the need for them to be easily accessible by worksites. In response to this need, a website was developed that not only gives worksites immediate access to the tools but also allows developers to easily modify and update tools and resources when necessary. Results from the reliability and pilot testing were published in Health Promotion Practice (see ‘Additional Information’).  The development of the social marketing component (i.e., Mix-it-Up campaign) consisted of a three-phase research process: (1) examination of current vending habits, beliefs, and motivations; (2) collection and assessment of consumer input to optimize message development; (3) in-market testing of messages to evaluate its influence on purchasing behavior.  As a result of this research, two different social marketing kits (one for blue collar and one for white collar employees) were created to promote healthy snacking habits in the workplace.

Process Evaluation:  Healthy Vending Iowa was evaluated in 13 worksites.  The worksites varied by sector (public or private), number of employees (range of 30 to 1,200), and number of vending machines at each worksite (range of 2 to 10).  The worksites completed an electronic survey and submitted meeting minutes, action plans or other relevant materials documenting implementation of the initiative.  All worksites were required to work with vendors to identify healthy options, do product testings with employees, market healthy vending options, and use employee incentives.  Process evaluation findings were based on summary reports from the worksites and are as follows:

  • Worksite collaborations with vendors ranged from discussion on how to identify healthier snacks to the development of an addendum to the vendor contract to include at least 30% of healthy foods in vending machines.
  • All worksites worked with their vendors to do product testings.  For example, one worksite employing over 100 people held a taste testing event to sample healthy options like baked chips; over 55 employees attended this event.  Some worksites also surveyed employees on which items they liked best and would most likely purchase from the machine.
  • The worksites used the social marketing materials to support healthier snacking, such as including healthier snacking information in the worksite’s monthly newsletter or placing healthy vending signage near vending machines.
  • Employee incentives, such as water bottles or cutting boards, were used to motivate employees to make healthy snack choices.

Outcome Evaluation: Outcome evaluation for Healthy Vending Iowa was based on results from pre- and post- NEMS-V assessments of vending machines conducted by the 13 worksites and on individual worksite reports that documented policy development.  Outcome evaluation findings are as follows:

  • All 13 worksites reported increased availability of healthy options in at least 1 snack or beverage machine.  For example, the availability of healthy options (i.e., the % of yellow and green options) was 10% at pre-assessment and increased to 46% at post-assessment for a cafeteria vending machine in a regional medical center with 425 employees.  For many worksites, increased availability of healthy options occurred in multiple vending machines at the worksite (e.g., in 5 of 9 or 8 of 10 vending machines). 
  • All 13 worksites worked to develop vendor and/or worksite policies requiring a minimum of 30% healthy food or beverage options in vending machines. Two worksites added an addendum to their vendor contracts for 30% healthy food or beverage options in their vending machines.  One worksite with 4 vending machines drafted and implemented a new healthy vending machine policy.