Table 1.

Study design 1A: Key features

Aim	Objectives	Strategies	Process Evaluation (Assessment of whether strategies were implemented as intended)	Impact evaluation (Assessment of whether objectives were achieved)	Outcome evaluation (Assessment of whether aims were achieved)
To improve food security and diet in the commun-ities on the APY Lands	To: (i) improve food supply (availability, affordability, placement, promotion) and (ii) increase demand for healthy food In all stores on the APY Lands (n=8)	Business as usual 2014-mid-2022 - all stores/times with exception of below: (i and ii) Monitoring and surveillance of food availability, placement and promotion in all stores on the APY Lands (n=8); feedback results to store groups/communities Monitoring of food price all stores, including convenience store outside APY Lands and supermarkets in Alice Springs 2018-2019: (i) early 2018 revision of updated nutrition policy in 5 Mai Wiru community stores, with supported implementation from mid-2018 to mid-2019 by a specifically employed project officer in two Mai Wiru stores in the intervention focus communities (ii) community-led nutrition promotion/ food literacy/food sovereignty/budgeting activities from mid-2018 to mid-2019 by the project officer in the two intervention focus communities	All stores, all times Quantity, reach, quality of monitoring, surveillance, reporting and feedback strategies Mid-2018 to mid-2019 (i) Quantity, reach, quality of store nutrition support strategies provided to the two intervention focus communities (ii) Quantity, reach, quality of nutrition support activities provided to the two intervention focus communities	All stores, all times Assessment of food availability, affordability, accessibility, acceptability, advertising/promotion (regular store audits against revised store nutrition policy) Comparison of results in groups of communities (by three intervention levels)	All stores, all times Assessment of community diet (validated store-turnover: pre and post study where available) Comparison of results in intervention focus and other groups of communities (by three intervention levels) Relationship between process, impact and outcome measures

Community/store codes:

• Participating communities/stores (n=12) on APY Lands (n=8) and in control communities/ outside APY Lands (n=4), comprising:

• Intervention focus communities with Mai Wiru stores (n=2). Codes: IMW1 and IMW2

• Nutrition Policy Control communities/stores with Mai Wiru stores (n=3) Codes: PCMW3, PCMW4, PCMW5 (business as usual, with introduction of revised Mai Wiru store nutrition policy early in 2018).

• Other Control communities/stores on APY Lands with non-Mai Wiru stores (n=3) Codes: CAPY6, CAPY7, CAPY8 (business as usual)

• Comparison Convenience Store located close to, but outside, the APY Lands (n=1) Codes CS9 (price data only)

• Regional centre Comparison supermarkets in Alice Springs (n=2) Codes: CAS10, CAS11 (price data only). At community request from January 2019, a supermarket popular with Aboriginal customers (CAS12) was added to the survey (total n=3)