NCT03252158

Altering the Availability of Healthier vs. Less Healthy Items in Vending Machines

Completed NA Last updated 3 May 2018

What this trial tests

NA trial testing Availability of healthier vs. less healthy foods in Healthy Diet in 10 participants. Completed in 28 March 2018.

Timeline

17 August 2017

Primary endpoint
28 March 2018

28 March 2018

Quick facts

Lead sponsor	University of Cambridge
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	crossover
Masking	none
Primary purpose	basic science
Enrollment	10
Start date	17 August 2017
Primary completion	28 March 2018
Estimated completion	28 March 2018
Sites	1 location across United Kingdom

Drugs / interventions tested

• Availability of healthier vs. less healthy foods

Conditions studied

• Healthy Diet — all drugs for Healthy Diet →

Sponsor

University of Cambridge

Who can join

Eligibility, any sex, with Healthy Diet. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

Background: While there is some evidence that increasing the range of healthier foods and drinks and/or decreasing the range of less healthy options may increase healthier choices, more work is needed to establish the reproducibility of any effect. The current study aims to investigate the impact of altering the availability of healthier and less healthy foods and cold beverages in hospital vending machines.

Methods: An adapted multiple treatment reversal design will be used, in which all standard vending machines serving snack foods and/or cold beverages in one hospital in England change the number of slots containing (i) less healthy items and (ii) healthier items over eight 4-week periods. Changes will take place in a two-step process whereby decreases are implemented in a separate study period prior to increases in the contrasting food group. Following a 4-week baseline period, all vending machines will be standardised to have 75% healthier drinks and/or 25% healthier snacks (study period 1). Vending machines (n=9) will be randomly allocated to the order in which they: (1) decrease less healthy foods and increase healthier foods or (2) decrease healthier foods and increase less healthy foods (study periods 2\&3 and 5\&6). After each decrease-increase pair, machines will return to the standardised 75% healthier drinks and 25% healthier snacks (study periods 4 and 7). Sales data will be obtained via records of machine restocking.

Planned Analysis: The impact of the availability intervention will be assessed in separate linear mixed models for cold drinks and snacks, examining the impact on total energy (kcal) purchased, per restocking interval, with random effects for vending machine.

Publications & conference data

3 peer-reviewed publications reference this trial (live from Europe PMC):

1. Altering the availability or proximity of food, alcohol, and tobacco products to change their selection and consumption.
   Hollands GJ, Carter P, Anwer S, King SE, et al · · 2019 · cited 60× · PMID 31482606 · DOI 10.1002/14651858.cd012573.pub3
2. Altering the availability or proximity of food, alcohol, and tobacco products to change their selection and consumption.
   Hollands GJ, Carter P, Anwer S, King SE, et al · · 2019 · cited 34× · PMID 31452193 · DOI 10.1002/14651858.cd012573.pub2
3. Altering the availability of healthier vs. less healthy items in UK hospital vending machines: a multiple treatment reversal design.
   Pechey R, Jenkins H, Cartwright E, Marteau TM. · · 2019 · cited 15× · PMID 31775798 · DOI 10.1186/s12966-019-0883-5