Trial Outcomes & Findings for Increasing Engagement With a Healthy Food Benefit (NCT NCT02486588)

Last Updated: 2020-07-10

Results Overview

The difference in monthly healthy food expenditures between arms. This measure is defined as the monthly amount spent on healthy foods divided by the total monthly amount spent on food, multiplied by 100. For those individuals who had no recorded expenditure in a given month, they will be assigned 0% healthy food expenditure that month; in this way, this outcome can be considered a composite score of being engaged in the healthy food program (0%=not engaged) and the level of engagement (if monthly expenditure \>0). Each individual's data will be averaged across the intervention period.

Recruitment status

COMPLETED

Study phase

Target enrollment

7314 participants

Primary outcome timeframe

Monthly over 6 month intervention period

Results posted on

2020-07-10

Participant Flow

Participant milestones

Participant milestones
Measure	10% Cash, no Weekly Message, Standard Monthly SMS 10% cash back level, no weekly message, and the standard monthly message	10% Cash, General Weekly SMS, Standard Monthly SMS 10% cash back, general weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10% Cash, Personal Weekly SMS, Standard Monthly SMS 10 % cash back, personalized weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	25% Cash, Personal Weekly SMS, Standard Monthly SMS 25% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET Cash, Personal Weekly SMS, Standard Monthly SMS 10%+15% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET, Personal Weekly SMS, Unbundled Monthly SMS 10%+15% cash back, personal weekly message, unbundled monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study
Overall Study STARTED	1188	1252	1220	1206	1243	1205
Overall Study COMPLETED	450	502	465	468	497	459
Overall Study NOT COMPLETED	738	750	755	738	746	746

Reasons for withdrawal

Reasons for withdrawal
Measure	10% Cash, no Weekly Message, Standard Monthly SMS 10% cash back level, no weekly message, and the standard monthly message	10% Cash, General Weekly SMS, Standard Monthly SMS 10% cash back, general weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10% Cash, Personal Weekly SMS, Standard Monthly SMS 10 % cash back, personalized weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	25% Cash, Personal Weekly SMS, Standard Monthly SMS 25% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET Cash, Personal Weekly SMS, Standard Monthly SMS 10%+15% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET, Personal Weekly SMS, Unbundled Monthly SMS 10%+15% cash back, personal weekly message, unbundled monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study
Overall Study Randomized in error- ineligible	738	750	755	738	746	746

Baseline Characteristics

Increasing Engagement With a Healthy Food Benefit

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	10% Cash, no Weekly SMS, Standard Monthly SMS n=450 Participants 10% cash back level, no weekly message, and the standard monthly message	10% Cash, General Weekly SMS, Standard Monthly SMS n=502 Participants 10% cash back, general weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10% Cash Back, Personal Weekly SMS, Standard Monthly SMS n=465 Participants 10 % cash back, personalized weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	25% Cash Back, Personal Weekly SMS, Standard Monthly SMS n=468 Participants 25% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET Cash, Personal Weekly SMS, Standard Weekly SMS n=497 Participants 10%+15% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET Cash, Personal Weekly SMS, Unbundled Monthly SMS n=459 Participants 10%+15% cash back, personal weekly message, unbundled monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	Total n=2841 Participants Total of all reporting groups
Age, Continuous	47.9 years STANDARD_DEVIATION 11.8 • n=5 Participants	48.3 years STANDARD_DEVIATION 11.7 • n=7 Participants	47 years STANDARD_DEVIATION 11.6 • n=5 Participants	47.4 years STANDARD_DEVIATION 11.6 • n=4 Participants	47.7 years STANDARD_DEVIATION 11.9 • n=21 Participants	48.5 years STANDARD_DEVIATION 12 • n=8 Participants	47.8 years STANDARD_DEVIATION 11.8 • n=8 Participants
Sex: Female, Male Female	212 Participants n=5 Participants	225 Participants n=7 Participants	220 Participants n=5 Participants	207 Participants n=4 Participants	245 Participants n=21 Participants	212 Participants n=8 Participants	1321 Participants n=8 Participants
Sex: Female, Male Male	238 Participants n=5 Participants	277 Participants n=7 Participants	245 Participants n=5 Participants	261 Participants n=4 Participants	252 Participants n=21 Participants	247 Participants n=8 Participants	1520 Participants n=8 Participants
Household Size	3 people STANDARD_DEVIATION 1.3 • n=5 Participants	2.9 people STANDARD_DEVIATION 1.3 • n=7 Participants	3 people STANDARD_DEVIATION 1.2 • n=5 Participants	3 people STANDARD_DEVIATION 1.2 • n=4 Participants	2.9 people STANDARD_DEVIATION 1.2 • n=21 Participants	2.9 people STANDARD_DEVIATION 1.3 • n=8 Participants	2.9 people STANDARD_DEVIATION 1.2 • n=8 Participants
Vitality membership length	110.5 Weeks STANDARD_DEVIATION 56.9 • n=5 Participants	110.1 Weeks STANDARD_DEVIATION 56.2 • n=7 Participants	111.7 Weeks STANDARD_DEVIATION 58.3 • n=5 Participants	107.3 Weeks STANDARD_DEVIATION 55.6 • n=4 Participants	112.2 Weeks STANDARD_DEVIATION 58.2 • n=21 Participants	112.4 Weeks STANDARD_DEVIATION 57.8 • n=8 Participants	110.7 Weeks STANDARD_DEVIATION 57.1 • n=8 Participants
Region Gauteng	289 Participants n=5 Participants	329 Participants n=7 Participants	302 Participants n=5 Participants	326 Participants n=4 Participants	329 Participants n=21 Participants	291 Participants n=8 Participants	1866 Participants n=8 Participants
Region Kwazulu-Natal	39 Participants n=5 Participants	41 Participants n=7 Participants	46 Participants n=5 Participants	35 Participants n=4 Participants	51 Participants n=21 Participants	43 Participants n=8 Participants	255 Participants n=8 Participants
Region Western Cape	86 Participants n=5 Participants	102 Participants n=7 Participants	76 Participants n=5 Participants	72 Participants n=4 Participants	83 Participants n=21 Participants	85 Participants n=8 Participants	504 Participants n=8 Participants
Region Other	36 Participants n=5 Participants	30 Participants n=7 Participants	41 Participants n=5 Participants	35 Participants n=4 Participants	34 Participants n=21 Participants	40 Participants n=8 Participants	216 Participants n=8 Participants
Shopping trips	7.9 trips per month STANDARD_DEVIATION 4.4 • n=5 Participants	7.9 trips per month STANDARD_DEVIATION 4.1 • n=7 Participants	8.1 trips per month STANDARD_DEVIATION 4 • n=5 Participants	7.7 trips per month STANDARD_DEVIATION 4.3 • n=4 Participants	7.9 trips per month STANDARD_DEVIATION 4.1 • n=21 Participants	8.3 trips per month STANDARD_DEVIATION 4.2 • n=8 Participants	8 trips per month STANDARD_DEVIATION 4.2 • n=8 Participants
Monthly healthy spending	895 Rand (South African currency) per month STANDARD_DEVIATION 548.9 • n=5 Participants	923.4 Rand (South African currency) per month STANDARD_DEVIATION 608.9 • n=7 Participants	851.8 Rand (South African currency) per month STANDARD_DEVIATION 511.9 • n=5 Participants	843.5 Rand (South African currency) per month STANDARD_DEVIATION 506 • n=4 Participants	878.9 Rand (South African currency) per month STANDARD_DEVIATION 540.5 • n=21 Participants	901.1 Rand (South African currency) per month STANDARD_DEVIATION 521.4 • n=8 Participants	883.4 Rand (South African currency) per month STANDARD_DEVIATION 541.9 • n=8 Participants
Monthly unhealthy spending	558.3 Rand (South African currency) per month STANDARD_DEVIATION 347.1 • n=5 Participants	539 Rand (South African currency) per month STANDARD_DEVIATION 302.2 • n=7 Participants	549 Rand (South African currency) per month STANDARD_DEVIATION 326.1 • n=5 Participants	515 Rand (South African currency) per month STANDARD_DEVIATION 303.6 • n=4 Participants	532 Rand (South African currency) per month STANDARD_DEVIATION 313 • n=21 Participants	526.6 Rand (South African currency) per month STANDARD_DEVIATION 332.4 • n=8 Participants	536.5 Rand (South African currency) per month STANDARD_DEVIATION 320.6 • n=8 Participants
Monthly neutral spending	1823.5 Rand (South African Currency) per month STANDARD_DEVIATION 963.5 • n=5 Participants	1760.5 Rand (South African Currency) per month STANDARD_DEVIATION 881.9 • n=7 Participants	1818.8 Rand (South African Currency) per month STANDARD_DEVIATION 944.6 • n=5 Participants	1727.3 Rand (South African Currency) per month STANDARD_DEVIATION 888.4 • n=4 Participants	1736.5 Rand (South African Currency) per month STANDARD_DEVIATION 930.6 • n=21 Participants	1786.6 Rand (South African Currency) per month STANDARD_DEVIATION 900.5 • n=8 Participants	1774.6 Rand (South African Currency) per month STANDARD_DEVIATION 918.1 • n=8 Participants
Monthly healthy items	36.1 Items per month STANDARD_DEVIATION 21.2 • n=5 Participants	37.5 Items per month STANDARD_DEVIATION 23.7 • n=7 Participants	34.9 Items per month STANDARD_DEVIATION 20.5 • n=5 Participants	34.8 Items per month STANDARD_DEVIATION 21 • n=4 Participants	35.9 Items per month STANDARD_DEVIATION 21.6 • n=21 Participants	37.1 Items per month STANDARD_DEVIATION 20.6 • n=8 Participants	36.1 Items per month STANDARD_DEVIATION 21.5 • n=8 Participants
Monthly unhealthy items	26.4 Items per month STANDARD_DEVIATION 18.4 • n=5 Participants	24.6 Items per month STANDARD_DEVIATION 14.9 • n=7 Participants	25.2 Items per month STANDARD_DEVIATION 15.8 • n=5 Participants	23.7 Items per month STANDARD_DEVIATION 15.1 • n=4 Participants	24.2 Items per month STANDARD_DEVIATION 15.4 • n=21 Participants	24.1 Items per month STANDARD_DEVIATION 16.4 • n=8 Participants	24.7 Items per month STANDARD_DEVIATION 16 • n=8 Participants
Monthly neutral items	53.7 Items per month STANDARD_DEVIATION 28.8 • n=5 Participants	51.8 Items per month STANDARD_DEVIATION 26.2 • n=7 Participants	52.8 Items per month STANDARD_DEVIATION 27 • n=5 Participants	50.2 Items per month STANDARD_DEVIATION 25.7 • n=4 Participants	50.7 Items per month STANDARD_DEVIATION 26.1 • n=21 Participants	52.2 Items per month STANDARD_DEVIATION 27 • n=8 Participants	51.9 Items per month STANDARD_DEVIATION 26.8 • n=8 Participants
Monthly proportion of spending on healthy foods	27.5 Percent of spending STANDARD_DEVIATION 10.4 • n=5 Participants	28.3 Percent of spending STANDARD_DEVIATION 11.8 • n=7 Participants	26.6 Percent of spending STANDARD_DEVIATION 9.7 • n=5 Participants	27.7 Percent of spending STANDARD_DEVIATION 10.2 • n=4 Participants	27.9 Percent of spending STANDARD_DEVIATION 10.5 • n=21 Participants	28.5 Percent of spending STANDARD_DEVIATION 11.4 • n=8 Participants	27.7 Percent of spending STANDARD_DEVIATION 10.7 • n=8 Participants
Monthly proportion of spending on unhealthy foods	17.8 Percent of spending STANDARD_DEVIATION 7.6 • n=5 Participants	17.7 Percent of spending STANDARD_DEVIATION 7.3 • n=7 Participants	17.7 Percent of spending STANDARD_DEVIATION 7.6 • n=5 Participants	17.3 Percent of spending STANDARD_DEVIATION 6.8 • n=4 Participants	17.7 Percent of spending STANDARD_DEVIATION 7.5 • n=21 Participants	16.9 Percent of spending STANDARD_DEVIATION 7.5 • n=8 Participants	17.5 Percent of spending STANDARD_DEVIATION 7.4 • n=8 Participants
Monthly proportion of food items that were healthy	31.4 Percent of items STANDARD_DEVIATION 11.2 • n=5 Participants	32.5 Percent of items STANDARD_DEVIATION 12.7 • n=7 Participants	30.8 Percent of items STANDARD_DEVIATION 10.7 • n=5 Participants	32.1 Percent of items STANDARD_DEVIATION 11.3 • n=4 Participants	32.2 Percent of items STANDARD_DEVIATION 11.6 • n=21 Participants	33.1 Percent of items STANDARD_DEVIATION 12.8 • n=8 Participants	32 Percent of items STANDARD_DEVIATION 11.8 • n=8 Participants
Monthly proportion of food items that were unhealthy	22.6 Percent of items STANDARD_DEVIATION 9.5 • n=5 Participants	22.1 Percent of items STANDARD_DEVIATION 9.3 • n=7 Participants	22.5 Percent of items STANDARD_DEVIATION 9.4 • n=5 Participants	21.9 Percent of items STANDARD_DEVIATION 9 • n=4 Participants	22.1 Percent of items STANDARD_DEVIATION 9.2 • n=21 Participants	21.1 Percent of items STANDARD_DEVIATION 9.3 • n=8 Participants	22.1 Percent of items STANDARD_DEVIATION 9.3 • n=8 Participants

PRIMARY outcome

Timeframe: Monthly over 6 month intervention period

Outcome measures

Outcome measures
Measure	10% Cash, no Weekly SMS, Standard Monthly SMS n=450 Participants 10% cash back level, no weekly message, and the standard monthly message	10% Cash, General Weekly SMS, Standard Monthly SMS n=502 Participants 10% cash back, general weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10% Cash, Personal Weekly SMS, Standard Monthly SMS n=465 Participants 10 % cash back, personalized weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	25% Cash, Personal Weekly SMS, Standard Monthly SMS n=468 Participants 25% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15% Cash, Personal Weekly SMS, Standard Monthly SMS n=497 Participants 10%+15% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET Cash, Personal Weekly SMS, Unbundled Monthly SMS n=459 Participants 10%+15% cash back, personal weekly message, unbundled monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study
Monthly % Healthy Food Expenditure	24.8 Percentage of money per month Standard Deviation 11.4	26.8 Percentage of money per month Standard Deviation 12.9	24.9 Percentage of money per month Standard Deviation 11.7	25.7 Percentage of money per month Standard Deviation 11.5	25.9 Percentage of money per month Standard Deviation 12.7	26.5 Percentage of money per month Standard Deviation 13

SECONDARY outcome

Timeframe: Monthly over 6 month intervention period

The difference in monthly unhealthy food expenditures between arms. This measure is defined as the monthly amount spent on unhealthy foods divided by the total monthly amount spent on food, multiplied by 100. The average over the full intervention months will be calculated within an individual and compared between arms. To be complementary with the primary endpoint analysis, in a month where an individual is not engaged in the program (0 total monthly expenditure) the worst-score (100) is imputed for that month. A similar MI approach will also be conducted as a sensitivity analysis.

Outcome measures

Outcome measures
Measure	10% Cash, no Weekly SMS, Standard Monthly SMS n=450 Participants 10% cash back level, no weekly message, and the standard monthly message	10% Cash, General Weekly SMS, Standard Monthly SMS n=502 Participants 10% cash back, general weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10% Cash, Personal Weekly SMS, Standard Monthly SMS n=465 Participants 10 % cash back, personalized weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	25% Cash, Personal Weekly SMS, Standard Monthly SMS n=468 Participants 25% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15% Cash, Personal Weekly SMS, Standard Monthly SMS n=497 Participants 10%+15% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET Cash, Personal Weekly SMS, Unbundled Monthly SMS n=459 Participants 10%+15% cash back, personal weekly message, unbundled monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study
Monthly % Unhealthy Food Expenditure	24.4 Percentage of money per month Standard Error 20.1	21.7 Percentage of money per month Standard Error 17.2	22.4 Percentage of money per month Standard Error 17.7	21.7 Percentage of money per month Standard Error 17.1	23.9 Percentage of money per month Standard Error 19.9	22.3 Percentage of money per month Standard Error 19.1

SECONDARY outcome

Timeframe: Monthly over 6 month intervention period

The difference in monthly healthy food items purchased between arms. This measure is defined as the monthly number of healthy food items divided by the total monthly number of food items. The average over the full intervention months will be calculated within an individual and compared between arms. To be complementary with the primary endpoint analysis, in a month where an individual is not engaged in the program (0 total monthly expenditure) the worst-score (0) is imputed for that month. A similar MI approach will also be conducted as a sensitivity analysis.

Outcome measures

Outcome measures
Measure	10% Cash, no Weekly SMS, Standard Monthly SMS n=450 Participants 10% cash back level, no weekly message, and the standard monthly message	10% Cash, General Weekly SMS, Standard Monthly SMS n=502 Participants 10% cash back, general weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10% Cash, Personal Weekly SMS, Standard Monthly SMS n=465 Participants 10 % cash back, personalized weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	25% Cash, Personal Weekly SMS, Standard Monthly SMS n=468 Participants 25% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15% Cash, Personal Weekly SMS, Standard Monthly SMS n=497 Participants 10%+15% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET Cash, Personal Weekly SMS, Unbundled Monthly SMS n=459 Participants 10%+15% cash back, personal weekly message, unbundled monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study
Monthly % Healthy Items	27.8 Percentage of items per month Standard Deviation 12.5	30.2 Percentage of items per month Standard Deviation 13.9	28.4 Percentage of items per month Standard Deviation 12.7	29.5 Percentage of items per month Standard Deviation 12.8	28.9 Percentage of items per month Standard Deviation 13.6	30 Percentage of items per month Standard Deviation 14.5

SECONDARY outcome

Timeframe: Monthly over 6 month intervention period

The difference in monthly unhealthy food items purchased between arms. This measure is defined as the monthly number of unhealthy food items divided by the total monthly number of food items. The average over the full intervention months will be calculated within an individual and compared between arms. To be complementary with the primary endpoint analysis, in a month where an individual is not engaged in the program (0 total monthly expenditure) the worst-score (100) is imputed for that month. A similar MI approach will also be conducted as a sensitivity analysis.

Outcome measures

Outcome measures
Measure	10% Cash, no Weekly SMS, Standard Monthly SMS n=450 Participants 10% cash back level, no weekly message, and the standard monthly message	10% Cash, General Weekly SMS, Standard Monthly SMS n=502 Participants 10% cash back, general weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10% Cash, Personal Weekly SMS, Standard Monthly SMS n=465 Participants 10 % cash back, personalized weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	25% Cash, Personal Weekly SMS, Standard Monthly SMS n=468 Participants 25% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15% Cash, Personal Weekly SMS, Standard Monthly SMS n=497 Participants 10%+15% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET Cash, Personal Weekly SMS, Unbundled Monthly SMS n=459 Participants 10%+15% cash back, personal weekly message, unbundled monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study
Monthly % Unhealthy Items	29.4 Percentage of items per month Standard Deviation 19.8	26.6 Percentage of items per month Standard Deviation 17.5	27.2 Percentage of items per month Standard Deviation 17.7	26.3 Percentage of items per month Standard Deviation 17.2	28.5 Percentage of items per month Standard Deviation 19.8	26.9 Percentage of items per month Standard Deviation 19.2

SECONDARY outcome

Timeframe: During the 6 month intervention period

Examining the difference in healthy food expenditure trends between arms where the % health food expenditure is defined as describe for outcome 1 (above)

Outcome measures

Outcome measures
Measure	10% Cash, no Weekly SMS, Standard Monthly SMS n=450 Participants 10% cash back level, no weekly message, and the standard monthly message	10% Cash, General Weekly SMS, Standard Monthly SMS n=502 Participants 10% cash back, general weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10% Cash, Personal Weekly SMS, Standard Monthly SMS n=465 Participants 10 % cash back, personalized weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	25% Cash, Personal Weekly SMS, Standard Monthly SMS n=468 Participants 25% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15% Cash, Personal Weekly SMS, Standard Monthly SMS n=497 Participants 10%+15% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET Cash, Personal Weekly SMS, Unbundled Monthly SMS n=459 Participants 10%+15% cash back, personal weekly message, unbundled monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study
Percentage Change in Monthly % Healthy Food Expenditures Between Arms	-.0839 percentage change in % healthy spending Standard Error .0062	-.0777 percentage change in % healthy spending Standard Error .0059	-.0717 percentage change in % healthy spending Standard Error .0061	-.0769 percentage change in % healthy spending Standard Error .0062	-.0729 percentage change in % healthy spending Standard Error .0059	-.0742 percentage change in % healthy spending Standard Error .0062

SECONDARY outcome

Timeframe: During the 6 month intervention period

Examining the difference in unhealthy food expenditure trends between arms where %unhealthy food expenditure is defined as described for Outcome 2 (above).

Outcome measures

Outcome measures
Measure	10% Cash, no Weekly SMS, Standard Monthly SMS n=450 Participants 10% cash back level, no weekly message, and the standard monthly message	10% Cash, General Weekly SMS, Standard Monthly SMS n=502 Participants 10% cash back, general weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10% Cash, Personal Weekly SMS, Standard Monthly SMS n=465 Participants 10 % cash back, personalized weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	25% Cash, Personal Weekly SMS, Standard Monthly SMS n=468 Participants 25% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15% Cash, Personal Weekly SMS, Standard Monthly SMS n=497 Participants 10%+15% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET Cash, Personal Weekly SMS, Unbundled Monthly SMS n=459 Participants 10%+15% cash back, personal weekly message, unbundled monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study
Percent Change in Monthly %Unhealthy Food Expenditures Between Arms	.0836 Percent change in % unhealthy food spend Standard Error .0100	.0679 Percent change in % unhealthy food spend Standard Error .0095	.0579 Percent change in % unhealthy food spend Standard Error .0099	.0823 Percent change in % unhealthy food spend Standard Error .0098	.0928 Percent change in % unhealthy food spend Standard Error .0095	.0786 Percent change in % unhealthy food spend Standard Error .0099

SECONDARY outcome

Timeframe: During the 6 month intervention period

Examining the difference in proportion healthy food item trends between arms where % healthy food items is defined as described for Outcome 3 (above)

Outcome measures

Outcome measures
Measure	10% Cash, no Weekly SMS, Standard Monthly SMS n=450 Participants 10% cash back level, no weekly message, and the standard monthly message	10% Cash, General Weekly SMS, Standard Monthly SMS n=502 Participants 10% cash back, general weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10% Cash, Personal Weekly SMS, Standard Monthly SMS n=465 Participants 10 % cash back, personalized weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	25% Cash, Personal Weekly SMS, Standard Monthly SMS n=468 Participants 25% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15% Cash, Personal Weekly SMS, Standard Monthly SMS n=497 Participants 10%+15% cash back, personal weekly message, standard monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study	10+15%NET Cash, Personal Weekly SMS, Unbundled Monthly SMS n=459 Participants 10%+15% cash back, personal weekly message, unbundled monthly message Messaging: See detailed study description for overview of the different messaging interventions in this study Financial incentives: See detailed study description for overview of the different financial incentive-based interventions in this study
Percent Change for Monthly % Healthy Food Items Between Arms	-.0753 Percent change in % healthy food items Standard Error .0066	-.0650 Percent change in % healthy food items Standard Error .0062	-.0571 Percent change in % healthy food items Standard Error .0064	-.0659 Percent change in % healthy food items Standard Error .0064	-.0684 Percent change in % healthy food items Standard Error .0062	-.0722 Percent change in % healthy food items Standard Error .0065

SECONDARY outcome

Timeframe: During the 6 month intervention period

Examining the difference in proportion unhealthy food item trends between arms where % unhealthy food items is defined as described for Outcome 5 (above).