Diabetes Mellitus, Type 2, Diet, Healthy, Pre-diabetes
Conditions
Keywords
grocery shopping, online shopping, diabetes, behavioral economics, diet
Brief summary
425 million adults live with diabetes worldwide, and the prevalence of Type 2 diabetes is rising. Dietary approaches are recommended for weight control and diabetes management, but modern environments, characterized by plentiful, unhealthy foods, pose challenges to selecting a healthy diet. Behavioral economics offers a framework for modifying the food environment to encourage individuals with diabetes to select low-calorie and low-sugar foods. The goal of this study is to test novel approaches informed by behavioral economics to promote healthier grocery shopping among diabetic patients. Adults who have Type 2 diabetes or who are at risk for developing Type 2 diabetes will be recruited. Participants will be randomly assigned to 1 of 2 interventions or a control group in which they will shop in-person as usual. The Online intervention will utilize online grocery shopping to promote healthier purchasing. The Defaults intervention will augment this intervention, showing participants a default shopping cart pre-filled with items that correspond to the DASH diet and diabetic diet goals, which they may modify as they like. Receipt data will be collected to quantify the alignment of purchases with diabetic diet goals before, during, and after interventions. Purchases lower in calories, carbohydrates, and sugar and higher in nutritional quality (DASH diet score) are expected in the Defaults group; the Online group is expected to have intermediary results between Defaults and Controls. The investigators will also explore effects of the interventions on spending and dietary intake. This study is intended to demonstrate the efficacy of strategies that leverage behavioral economics principles to make the purchasing of healthier foods easier. The strategies have translational significance as they could be incorporated into clinical treatment, with the potential to improve dietary intake, glucose regulation, weight, and medication needs among diabetic patients.
Detailed description
The goal of this study is to test the effects of interventions informed by behavioral economics on the healthfulness of grocery purchases among diabetic adults. This study has a 3-group experimental design; adult patients with diabetes or at risk for diabetes who typically grocery shop in-person will be randomly assigned to one of two interventions or a control group. In all groups, recipe cards that follow the evidence-based DASH diet and correspond to dietary recommendations for diabetic patients will be provided. In addition, the first intervention, Online, will utilize online grocery shopping at a local grocery store to promote healthier purchasing, with a goal of removing visceral factors that can lead to impulse purchases in stores. The second intervention, Defaults, will augment the Online intervention, showing participants a default shopping cart when they log into their accounts. They will be told that their cart has been filled with items that conform to a diabetic diet and can be used to make the recipes from the provided recipe cards, and that they may modify their carts as they like. In the control group, participants will shop in-person as usual. At baseline, all participants will complete a survey online or via phone and then will grocery shop in-person as usual. Participants will then be randomized and receive further instructions. For the next 3 weeks, they will receive recipe cards and shop in accordance with their assigned study group. The following week (post), they will grocery shop using the mode of their choice (in-person or online) and complete a survey again. Household receipt data will be collected throughout the study. The baseline period will also serve as a run-in period, and participants whose diabetes/prediabetes status is not confirmed by a physician or who do not comply with study guidelines for baseline procedures will not be randomized for further participation. Primary analyses will examine intervention effects on grocery purchases, with additional analyses examining spending and dietary intake. All participant interactions will occur online or via phone, with cards for participant payment sent via postal mail. The specific aims of this study are: (1) to test effects of Online and Defaults interventions on diabetic adults' grocery purchases and (2) to explore effects of the Online and Defaults interventions on participants' spending during grocery shopping. It is hypothesized that (1a) purchases made by adults in the Defaults group will be lower in calories, carbohydrates, and sugar and higher in nutritional quality (DASH diet score) at post-test versus other study groups, (1b) adults in the Defaults group will show the greatest increases in nutritional quality versus other study groups, (1c) the Online group will have intermediary results between Defaults and Controls, and (2) there will be no difference in total dollars depicted on receipts across study groups during the intervention period (i.e. the costs of online shopping will be offset by effects of the Online and Default interventions).
Interventions
BEHAVIORALOnline - use of online grocery shopping platform
The Online intervention will utilize online grocery shopping (shopping at a local grocery store via online platform).
BEHAVIORALDefault - use of online grocery shopping platform with default shopping carts
The Defaults intervention, will augment the Online intervention, showing participants a default cart when they log into their online grocery shopping accounts. They will be told that their cart has been filled with items that conform to a diabetic diet and can be used to make the recipes from provided recipe cards, and that they may modify their cart as they like.
Sponsors
National Center for Advancing Translational Sciences (NCATS)
State University of New York at Buffalo
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Must be at least 18 years old * Must have been diagnosed diabetes or demonstrate diabetes risk as defined by the American Diabetes Association * Must shop in-person at select local grocery stores at least weekly, and at least 75% of the grocery shopping for the household must be done at these stores * Must do at least 75% of the grocery shopping for the household * Must speak English
Exclusion criteria
* Is under 18 years of age * Does not meet diabetes/risk for diabetes criteria * Does not shop in-person at select local grocery stores at least weekly * Does not live in a household in which 75% of groceries come from select local grocery stores * Does not do at least 75% of the grocery shopping for the household * Does not speak English * Receives SNAP or WIC benefits (an exclusion criterion for this study due to incompatibility of EBT cards with the selected online grocery shopping platform at this time) * Has dietary restrictions or preferences that would not allow them to reasonably partake in the study (i.e. they would not be willing or able to buy/eat many of the staple foods included in default carts/recipe cards)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Nutritional Quality of Purchases | Baseline (week 1), intervention (weeks 2-4), and post-test (week 5) | Nutritional quality of grocery purchases was created using indicators adapted from Fung 2008: fruit, vegetables, nuts/legumes, whole grains, low-fat dairy, sodium, red/processed meat, carbohydrates. Quintiles were calculated for each, using the number of items from a food group or sodium \[mg\] and carbohydrates \[g\] purchased that week. Resulting scores from 1-5 indicate whether participants were lower or higher on each indicator (red meat, sodium, carbohydrates reverse scored). The 8 scores were summed for a total nutritional quality score ranging from 8 to 40 (40=highest nutritional quality) |
| Sugars Purchased | At post-test (week 5) | Receipt data will be entered into Nutritionist Pro and will be used to calculate sugars purchased from target grocery stores. |
| Change in Sugars Purchased | Baseline (week 1), intervention (weeks 2-4), and post-test (week 5) | Receipt data will be entered into Nutritionist Pro and will be used to calculate changes in sugars purchased from target grocery stores. |
| Nutritional Quality of Purchases | At post-test (week 5) | Nutritional quality of grocery purchases was created using indicators adapted from Fung 2008: fruit, vegetables, nuts/legumes, whole grains, low-fat dairy, sodium, red/processed meat, carbohydrates. Quintiles were calculated for each, using the number of items from a food group or sodium \[mg\] and carbohydrates \[g\] purchased that week. Resulting scores from 1-5 indicate whether participants were lower or higher on each indicator (red meat, sodium, carbohydrates reverse scored). The 8 scores were summed for a total nutritional quality score ranging from 8 to 40 (40=highest nutritional quality). |
| Calories Purchased | At post-test (week 5) | Receipt data will be entered into Nutritionist Pro software and will be used to calculate total calories purchased from target grocery stores. |
| Change in Calories Purchased | Baseline (week 1), intervention (weeks 2-4), and post-test (week 5) | Receipt data will be entered into Nutritionist Pro and will be used to calculate changes in total calories purchased from target grocery stores. |
| Carbohydrates Purchased | At post-test (week 5) | Receipt data will be entered into Nutritionist Pro and will be used to calculate carbohydrates purchased from target grocery stores. |
| Change in Carbohydrates Purchased | Baseline (week 1), intervention (weeks 2-4), and post-test (week 5) | Receipt data will be entered into Nutritionist Pro and will be used to calculate changes in carbohydrates purchased from target grocery stores. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Dollars Spent | Baseline (week 1), intervention (weeks 2-4), and post-test (week 5) | Changes in total dollars spent at the target grocery stores from submitted receipts |
| Nutritional Quality of Foods Consumed | At post-test (week 5) | Nutritional quality of grocery purchases was created from food frequency questionnaire data using indicators adapted from Fung 2008: fruit, vegetables, nuts/legumes, whole grains, low-fat dairy, sodium, red/processed meat, carbohydrates. Quintiles were calculated for each, using reports of the frequency that the food group or nutrient of interest was consumed over the past month. Resulting scores from 1-5 indicate whether participants were lower or higher on each indicator (red meat, sodium, carbohydrates reverse scored). The 8 scores were summed for a total nutritional quality score ranging from 8 to 40 (40=highest nutritional quality). |
| Dollars Spent | At post-test (week 5) | Total dollars spent at the target grocery stores from submitted receipts |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Group 1 - Control No intervention - participants will shop in-person as they usually would. Participants will receive recipe cards that follow the evidence-based DASH diet and correspond to dietary recommendations for diabetic patients. | 20 |
| Group 2 - Online Participants will utilize online grocery shopping (shopping at a local grocery store via an online platform). Participants will also receive recipe cards that follow the evidence-based DASH diet and correspond to dietary recommendations for diabetic patients.
Online - use of online grocery shopping platform: The Online intervention will utilize online grocery shopping (shopping at a local grocery store via online platform). | 21 |
| Group 3 - Default The default intervention will augment the Online intervention, showing participants a default cart when they log into their online grocery shopping accounts. They will be told that their cart has been filled with items that conform to a diabetic diet and can be used to make recipes from the provided recipe cards, and that they can modify it as they like. Participants will also receive recipe cards that follow the evidence-based DASH diet and correspond to dietary recommendations for diabetic patients.
Default - use of online grocery shopping platform with default shopping carts: The Defaults intervention, will augment the Online intervention, showing participants a default cart when they log into their online grocery shopping accounts. They will be told that their cart has been filled with items that conform to a diabetic diet and can be used to make the recipes from provided recipe cards, and that they may modify their cart as they like. | 23 |
| Total | 64 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 | FG002 |
|---|---|---|---|---|
| Overall Study | Withdrawal by Subject | 2 | 0 | 1 |
Baseline characteristics
| Characteristic | Group 1 - Control | Group 2 - Online | Group 3 - Default | Total |
|---|---|---|---|---|
| Age, Continuous | 56.8 Years STANDARD_DEVIATION 9.3 | 49.2 Years STANDARD_DEVIATION 12.8 | 53.7 Years STANDARD_DEVIATION 8.8 | 53.2 Years STANDARD_DEVIATION 10.7 |
| Education Bachelor's degree | 6 Participants | 5 Participants | 8 Participants | 19 Participants |
| Education Graduate degree | 8 Participants | 10 Participants | 8 Participants | 26 Participants |
| Education High school graduate or equivalent | 1 Participants | 0 Participants | 1 Participants | 2 Participants |
| Education Some college/associate's degree | 5 Participants | 6 Participants | 6 Participants | 17 Participants |
| Ethnicity (NIH/OMB) Hispanic or Latino | 0 Participants | 1 Participants | 1 Participants | 2 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 20 Participants | 20 Participants | 22 Participants | 62 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Nutritional quality of grocery purchases | 22.4 units on a scale STANDARD_DEVIATION 4.5 | 22.4 units on a scale STANDARD_DEVIATION 3.5 | 22.9 units on a scale STANDARD_DEVIATION 4.8 | 22.6 units on a scale STANDARD_DEVIATION 4.3 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 1 Participants | 2 Participants | 4 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 1 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 1 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) White | 19 Participants | 18 Participants | 21 Participants | 58 Participants |
| Region of Enrollment United States | 20 participants | 21 participants | 23 participants | 64 participants |
| Sex: Female, Male Female | 17 Participants | 18 Participants | 19 Participants | 54 Participants |
| Sex: Female, Male Male | 3 Participants | 3 Participants | 4 Participants | 10 Participants |
| Total carbohydrates purchased | 3335.7 grams STANDARD_DEVIATION 3175.3 | 2944.1 grams STANDARD_DEVIATION 2886.1 | 3009.2 grams STANDARD_DEVIATION 2269 | 3093.7 grams STANDARD_DEVIATION 2748.2 |
| Total energy purchased | 26116.3 kcal STANDARD_DEVIATION 26229.4 | 25832.2 kcal STANDARD_DEVIATION 26229.4 | 25481.3 kcal STANDARD_DEVIATION 16266.5 | 25799.8 kcal STANDARD_DEVIATION 21272.6 |
| Total sugar purchased | 1289.7 grams STANDARD_DEVIATION 1243.9 | 1355.7 grams STANDARD_DEVIATION 1132.9 | 1345.5 grams STANDARD_DEVIATION 1065.4 | 1330.8 grams STANDARD_DEVIATION 1129.4 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 21 | 0 / 21 | 0 / 23 |
| other Total, other adverse events | 0 / 21 | 0 / 21 | 0 / 23 |
| serious Total, serious adverse events | 0 / 21 | 0 / 21 | 0 / 23 |
Outcome results
Primary
Calories Purchased
Receipt data will be entered into Nutritionist Pro software and will be used to calculate total calories purchased from target grocery stores.
Time frame: At post-test (week 5)
Population: The sample sizes reflect the number of participants in each group who provided receipt data during Week 5 of the study
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Calories Purchased | 24443.30 Kcal | Standard Deviation 14918.22 |
| Group 2 - Online | Calories Purchased | 25339.20 Kcal | Standard Deviation 19069.6 |
| Group 3 - Default | Calories Purchased | 18527.35 Kcal | Standard Deviation 15025.35 |
Primary
Calories Purchased
Receipt data are entered into Nutritionist Pro software and used to calculate total calories purchased from target grocery stores each week. For this analysis, the weekly values were aggregated, such that the least squares means reported herein represent average calories purchased across all 5 weeks, in the context of the repeated measures ANOVA model.
Time frame: Weeks 1-5 (testing overall main effect of study group)
Population: All randomized participants were included in the repeated measures ANOVAs assessing the overall main effect of study group. Means reported below are least squares means representing calories purchased in each group overall across the time points
| Arm | Measure | Value (LEAST_SQUARES_MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Calories Purchased | 25768 Kcal | Standard Deviation 14908.1 |
| Group 2 - Online | Calories Purchased | 23479 Kcal | Standard Deviation 14870.5 |
| Group 3 - Default | Calories Purchased | 20236 Kcal | Standard Deviation 14948.3 |
Primary
Carbohydrates Purchased
Receipt data will be entered into Nutritionist Pro and will be used to calculate carbohydrates purchased from target grocery stores.
Time frame: At post-test (week 5)
Population: Represents those with receipt data at post-test (week 5)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Carbohydrates Purchased | 3320.09 grams | Standard Deviation 2231.52 |
| Group 2 - Online | Carbohydrates Purchased | 3153.88 grams | Standard Deviation 2805.51 |
| Group 3 - Default | Carbohydrates Purchased | 2417.95 grams | Standard Deviation 2056.82 |
Primary
Carbohydrates Purchased
Receipt data are entered into Nutritionist Pro and used to calculate carbohydrates purchased from target grocery stores each week. For this analysis, the weekly values were aggregated, such that the least squares means reported herein represent average carbohydrates (grams) purchased across all 5 weeks, in the context of the repeated measures ANOVA model.
Time frame: Weeks 1-5 (testing overall main effect of study group)
Population: All randomized participants were included in the repeated measures ANOVAs assessing the overall main effect of study group. Means reported below are least squares means representing carbohydrates purchased in each group overall across the time points
| Arm | Measure | Value (LEAST_SQUARES_MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Carbohydrates Purchased | 3200.85 grams | Standard Deviation 1961.8 |
| Group 2 - Online | Carbohydrates Purchased | 2760.89 grams | Standard Deviation 1955.66 |
| Group 3 - Default | Carbohydrates Purchased | 2502.41 grams | Standard Deviation 1968.88 |
Primary
Change in Calories Purchased
Receipt data will be entered into Nutritionist Pro and will be used to calculate changes in total calories purchased from target grocery stores.
Time frame: Baseline (week 1), intervention (weeks 2-4), and post-test (week 5)
Population: The intent of this analysis was to examine whether there were group differences in change in the specified outcome among all participants randomized. We report here the difference in least squares means within each group from week 1 to week 5.
| Arm | Measure | Value (LEAST_SQUARES_MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Change in Calories Purchased | -2661.91 kilocalories | Standard Error 4023.56 |
| Group 2 - Online | Change in Calories Purchased | -1533.34 kilocalories | Standard Error 4016.82 |
| Group 3 - Default | Change in Calories Purchased | -6892.76 kilocalories | Standard Error 3786.38 |
Primary
Change in Carbohydrates Purchased
Receipt data will be entered into Nutritionist Pro and will be used to calculate changes in carbohydrates purchased from target grocery stores.
Time frame: Baseline (week 1), intervention (weeks 2-4), and post-test (week 5)
Population: The intent of this analysis was to examine whether there were group differences in change in the specified outcome among all participants randomized. We report here the difference in least squares means within each group from week 1 to week 5.
| Arm | Measure | Value (LEAST_SQUARES_MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Change in Carbohydrates Purchased | -102.78 grams | Standard Error 621.18 |
| Group 2 - Online | Change in Carbohydrates Purchased | -119.84 grams | Standard Error 620.36 |
| Group 3 - Default | Change in Carbohydrates Purchased | -575.67 grams | Standard Error 588.96 |
Primary
Change in Nutritional Quality of Purchases
Nutritional quality of grocery purchases was created using indicators adapted from Fung 2008: fruit, vegetables, nuts/legumes, whole grains, low-fat dairy, sodium, red/processed meat, carbohydrates. Quintiles were calculated for each, using the number of items from a food group or sodium \[mg\] and carbohydrates \[g\] purchased that week. Resulting scores from 1-5 indicate whether participants were lower or higher on each indicator (red meat, sodium, carbohydrates reverse scored). The 8 scores were summed for a total nutritional quality score ranging from 8 to 40 (40=highest nutritional quality)
Time frame: Baseline (week 1), intervention (weeks 2-4), and post-test (week 5)
Population: The intent of this analysis was to examine whether there were group differences in change in the specified outcome among all participants randomized. We report here the difference in least squares means within each group from week 1 to week 5.
| Arm | Measure | Value (LEAST_SQUARES_MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Change in Nutritional Quality of Purchases | -1.47 units on a scale | Standard Error 1.13 |
| Group 2 - Online | Change in Nutritional Quality of Purchases | -2.04 units on a scale | Standard Error 1.13 |
| Group 3 - Default | Change in Nutritional Quality of Purchases | -1.39 units on a scale | Standard Error 1.06 |
Primary
Change in Sugars Purchased
Receipt data will be entered into Nutritionist Pro and will be used to calculate changes in sugars purchased from target grocery stores.
Time frame: Baseline (week 1), intervention (weeks 2-4), and post-test (week 5)
Population: The intent of this analysis was to examine whether there were group differences in change in the specified outcome among all participants randomized. We report here the difference in least squares means within each group from week 1 to week 5.
| Arm | Measure | Value (LEAST_SQUARES_MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Change in Sugars Purchased | -138.31 grams | Standard Error 265.25 |
| Group 2 - Online | Change in Sugars Purchased | -374.92 grams | Standard Error 264.84 |
| Group 3 - Default | Change in Sugars Purchased | -308.32 grams | Standard Error 249.56 |
Primary
Nutritional Quality of Purchases
Nutritional quality of grocery purchases was created using indicators adapted from Fung 2008: fruit, vegetables, nuts/legumes, whole grains, low-fat dairy, sodium, red/processed meat, carbohydrates. Quintiles were calculated for each, using the number of items from a food group or sodium \[mg\] and carbohydrates \[g\] purchased that week. Resulting scores from 1-5 indicate whether participants were lower or higher on each indicator (red meat, sodium, carbohydrates reverse scored). The 8 scores were summed for a total nutritional quality score ranging from 8 to 40 (40=highest nutritional quality).
Time frame: At post-test (week 5)
Population: Represents those with receipt data at post-test (week 5)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Nutritional Quality of Purchases | 20.89 units on a scale | Standard Deviation 4.37 |
| Group 2 - Online | Nutritional Quality of Purchases | 20.42 units on a scale | Standard Deviation 3.22 |
| Group 3 - Default | Nutritional Quality of Purchases | 21.55 units on a scale | Standard Deviation 3.02 |
Primary
Nutritional Quality of Purchases
Nutritional quality of grocery purchases was created using indicators adapted from Fung 2008: fruit, vegetables, nuts/legumes, whole grains, low-fat dairy, sodium, red/processed meat, carbohydrates. Quintiles were calculated for each, using the number of items from a food group or sodium \[mg\] and carbohydrates \[g\] purchased that week. Resulting scores from 1-5 indicate whether participants were lower or higher on each indicator (red meat, sodium, carbohydrates reverse scored). The 8 scores were summed for a total nutritional quality score ranging from 8 to 40 (40=highest nutritional quality).
Time frame: Weeks 1-5 (testing overall main effect of study group)
Population: All randomized participants analyzed in repeated measures ANOVA. Results reflect the average nutritional quality of purchases across all 5 study weeks (week 1-5) by group.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Nutritional Quality of Purchases | 20.95 units on a scale | Standard Deviation 2.55 |
| Group 2 - Online | Nutritional Quality of Purchases | 21.43 units on a scale | Standard Deviation 2.54 |
| Group 3 - Default | Nutritional Quality of Purchases | 23.86 units on a scale | Standard Deviation 2.56 |
Primary
Sugars Purchased
Receipt data will be entered into Nutritionist Pro and will be used to calculate sugars purchased from target grocery stores.
Time frame: At post-test (week 5)
Population: Represents those with receipt data at post-test (week 5)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Sugars Purchased | 1212.27 grams | Standard Deviation 985.07 |
| Group 2 - Online | Sugars Purchased | 1026.31 grams | Standard Deviation 809.66 |
| Group 3 - Default | Sugars Purchased | 1024.99 grams | Standard Deviation 873.16 |
Primary
Sugars Purchased
Receipt data are entered into Nutritionist Pro software and used to calculate total sugar purchased from target grocery stores each week. For this analysis, the weekly values were aggregated, such that the least squares means reported herein represent average sugar (grams) purchased across all 5 weeks, in the context of the repeated measures ANOVA model.
Time frame: Weeks 1-5 (testing overall main effect of study group)
Population: All randomized participants were included in the repeated measures ANOVAs assessing the overall main effect of study group. Means reported below are least squares means representing calories purchased in each group overall across the time points
| Arm | Measure | Value (LEAST_SQUARES_MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Sugars Purchased | 1271.2 grams | Standard Deviation 905.47 |
| Group 2 - Online | Sugars Purchased | 1110.85 grams | Standard Deviation 902.9 |
| Group 3 - Default | Sugars Purchased | 1035.17 grams | Standard Deviation 907.99 |
Secondary
Change in Dollars Spent
Changes in total dollars spent at the target grocery stores from submitted receipts
Time frame: Baseline (week 1), intervention (weeks 2-4), and post-test (week 5)
Population: The results below represent the change in dollars spent when purchasing groceries from target stores from week 1 to week 5 in each study group.
| Arm | Measure | Value (LEAST_SQUARES_MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Change in Dollars Spent | -7.20 dollars | Standard Error 11.78 |
| Group 2 - Online | Change in Dollars Spent | -8.65 dollars | Standard Error 11.76 |
| Group 3 - Default | Change in Dollars Spent | -24.72 dollars | Standard Error 11.09 |
Secondary
Dollars Spent
Total dollars spent at the target grocery stores from submitted receipts
Time frame: At post-test (week 5)
Population: Sample sizes reflect those providing receipt data in week 5.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Dollars Spent | 84.71 dollars | Standard Deviation 47.05 |
| Group 2 - Online | Dollars Spent | 88.79 dollars | Standard Deviation 61.52 |
| Group 3 - Default | Dollars Spent | 72.59 dollars | Standard Deviation 42.19 |
Secondary
Dollars Spent
Total dollars spent at the target grocery stores from submitted receipts
Time frame: Weeks 1-5 (testing overall main effect of study group)
Population: Results reflect the least squares means in each group across all 5 weeks of receipt data collection in the context of the repeated measures ANOVA model. In other words, results below can be thought of as average dollars spent by each study group over the course of the 5-week study.
| Arm | Measure | Value (LEAST_SQUARES_MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Dollars Spent | 88.93 dollars | Standard Error 10.76 |
| Group 2 - Online | Dollars Spent | 87.64 dollars | Standard Error 10.74 |
| Group 3 - Default | Dollars Spent | 80.69 dollars | Standard Error 10.31 |
Secondary
Nutritional Quality of Foods Consumed
Nutritional quality of grocery purchases was created from food frequency questionnaire data using indicators adapted from Fung 2008: fruit, vegetables, nuts/legumes, whole grains, low-fat dairy, sodium, red/processed meat, carbohydrates. Quintiles were calculated for each, using reports of the frequency that the food group or nutrient of interest was consumed over the past month. Resulting scores from 1-5 indicate whether participants were lower or higher on each indicator (red meat, sodium, carbohydrates reverse scored). The 8 scores were summed for a total nutritional quality score ranging from 8 to 40 (40=highest nutritional quality).
Time frame: At post-test (week 5)
Population: The total sample size of participants with usable food frequency questionnaire is 55 out of the 65 randomized participants. The outcome data provided is from the final intake model; least squares means are provided for each study group after adjusting for two covariates that warranted inclusion in the model, participant gender and income.
| Arm | Measure | Value (LEAST_SQUARES_MEAN) | Dispersion |
|---|---|---|---|
| Group 1 - Control | Nutritional Quality of Foods Consumed | 20.99 units on a scale | Standard Error 1.32 |
| Group 2 - Online | Nutritional Quality of Foods Consumed | 21.13 units on a scale | Standard Error 1.35 |
| Group 3 - Default | Nutritional Quality of Foods Consumed | 22.00 units on a scale | Standard Error 1.33 |