Table 4b. Studies using a before-and-after design to assess change in fruit and vegetable intake.

						Key findings
Author	Year	n	Study design	Exposure	FV outcome	Exposure measured by survey	Exposure measured by store audit or other
Caldwell	2009	130	Broad intervention to achieve Healthy People 2010 objectives; Before-after design; no control group. Results estimate the association of each exposure with change in fruit and vegetable consumption from intervention baseline to intervention end.	Participant reported: Ease or difficulty in getting fresh produce; Store audit: shelf space, cost, variety, and quality	Change in fruit and vegetable consumption (servings per week), measured at the beginning and end of the intervention	Perceived access to fresh produce: β>0,β = 0.011	Square meters of fresh fruits and veg:  β > 0, β = 0.0137 Variety of fruit and fresh fruits and veg:  β > 0, β = 0.007 No. of stores in community:  β > 0, β = 0.0013 Produce freshness:  β > 0, β = 0.045 Minimum price of produce basket:  β > 0, β = 0.0022 § Minimum price of fresh produce:  β > 0, p = 0.0187 §
Cummins	2005	412	Before-after natural experiment forresidents who lived with 1 km of a newsupermarket; control site 5 km away. Results estimate difference in change in FV between groups.	Presence of a new supermarket within 1km of residence	Fruit and vegetable consumption (portions per day)		Participants with new stores not statistically significant
Wrigley	2003	598	Before-after natural experiment; no control group. Results estimate the before-after change in FV consumption.	Switching stores, distance to new store	Fruit and vegetable consumption, (s/d)	Switched from budget store to nev store, FV change: β>0, p <0.05 Switched to new store not statistical significant	Distance to the new store <= 500m: FV change: β>0, p <0.05

^§Association in the opposite direction from expected