Sotos‐Prieto 2017.

Trial name or title	Feeding America's Bravest: Mediterranean Diet‐Based Interventions to Change Firefighters' Eating Habits
Methods	A prospective, cluster‐randomised trial, with cross‐over of the control group after 1 year to compare a Mediterranean diet nutrition intervention (MDNI) versus usual care (control) in career firefighters within the Indianapolis Fire Department (IFD)
Participants	Inclusion criteria: Those permanently assigned to one of the 45 IFD stations With a fire department‐provided medical exam in the last 2 years At least 18 years of age Full duty status at the time of consent Exclusion criteria: Those without a recorded fire department exam in the last 2 years Less than 18 years of age Restrictions on duty at the time of consent.
Interventions	Mediterranean diet intervention: educational materials (online learning) will be provided via the study website; group educational sessions and written materials (brochure with Mediterranean diet recommendations, shopping list recommendations and sample recipes, specific Mediterranean diet pyramid); videos; educational sessions; in‐person chef‐led, Mediterranean cooking demonstrations. Peer‐education and support. Discounted food access: The investigators have partnered with Kroger supermarkets, a large national chain with numerous stores in the Indianapolis area, to provide discounted access to key Mediterranean foods for both participating firefighters and their families. Email or text message encouragement and reminders during the intervention. Control group: usual care, consisting of existing IFD health and wellness activities, with no investigator‐provided interventions. In phase I, Group 1 will receive the MDNI for 12 months. Phase II: Group 1 fire houses will cross‐over to "self‐sustained continuation," a less intense, self‐directed, maintenance phase for 12 months to examine longer‐term persistence of behaviour change after the active 12‐month MDNI. During self‐sustained continuation access to some environmental changes: such as discounted food access, peer education/support and online learning will remain; however, the stations will not receive investigator‐led educational sessions. In Phase II, Group 2 fire houses will cross‐over to receive the full active MDNI for 6 months. The Group 2 MDNI will test the efficacy of a shorter, but otherwise identical MDNI. It will be followed by a final 6 months of "self‐sustained continuation" (as described above) to examine the shorter MDNI's effect on persistence of adherence.
Outcomes	Primary outcome measures: Changes in Mediterranean diet scale (time Frame: 6, 12 and 24 months) 12 months change in the MD scores as well as 12‐ and 24‐month change in group 1; and 6‐ and 12‐month change from baseline to follow‐up in group 2 Secondary outcome measures: changes in BMI (m²/kg) (time frame: 24 months) Changes in weight (kg) (time frame: 24 months) Changes in waist circumference (cm) (time frame: 24 months) Changes in lipids (time frame: 24 months) LDL (mg/dl), HDL (mg/dl), total cholesterol Changes in inflammatory markers (time frame: 24 months) CRP (mg/L) Changes in biomarkers (time frame: 6 months) (tyrosol, hydroxytyrosol and plasma fatty acids)
Starting date	October 2016, estimated completion date September 2019
Contact information	Harvard TH Chan School of Public Health Boston, Massachusetts United States, 02115 Contact: Stefanos N Kales, MD, MPH 617‐665‐1580 (skales@hsph.harvard.edu) Contact: Mercedes Sotos Prieto, PhD 6178608979 (msotosp@hsph.harvard.edu)
Notes	NCT02941757

BMI: body mass index; CHD: coronary heart disease; CVD: cardiovascular disease; HDL: high‐density lipoprotein; LDL: low‐density lipoprotein; NAFLD: non‐alcoholic fatty liver disease; NICE: National Institute for Health and Care Excellence; RCT: randomised controlled trial