Cardiovascular Diseases, Diabetes Mellitus, Obesity
Conditions
Keywords
Plant-based diet, Behavioral nudge, Mail distribution, Randomized controlled trial, Insurance claims, Chronic disease, Letter-based intervention, Health behaviors, Prevention focus, Loss framing, Commitment, Provider testimonial
Brief summary
The researchers' mission is to promote healthier eating behavior and to reduce costs associated with healthcare. The purpose of this study is to evaluate the effects of mailing randomly selected participants a letter promoting a plant-based diet. Depending on the experimental condition, participants may additionally receive a free documentary, Forks Over Knives, and they may also get letters which use commitment- or prevention-focused messages to encourage watching the documentary and changing their eating behavior. The researchers hypothesize that receiving the documentary will be associated with lower insurance claims and improved health outcomes one and two years later. The researchers also hypothesize that using either commitment- or prevention-focused messages will also contribute to lower insurance claims and improved health outcomes compared to experimental conditions where materials did not include these messages. This study will help the researchers design evidence-supported programs that can improve people's health.
Detailed description
Note that participant selection and assignment will be done at the level of the household, but analysis of outcomes will include individual-level analysis. This analytic decision was made because the researchers assume that the intervention may potentially affect other members of the household. While one person in a household will be selected for matching the eligibility criteria, the mailed materials will be addressed to all adult members of the household (defined as adults 18+ who are the spouse or child of the selected member) who are members of the Geisinger Health Plan. Outcome data will be pulled from all adult members of the household who have data through the Geisinger Health Plan. The researchers will analyze the data using standard survey research analyses methods, including computing bivariate correlations, using general linear models, using non-parametric models for non-normally distributed insurance data, and entering variables as independent predictors in regression models to attempt to predict desired outcomes. The researchers will also use multilevel models to account for household- and individual-level data. The analysis of primary outcomes will focus on data one year after the intervention begins. Follow-up analysis on secondary outcomes will be conducted two years after the intervention begins. The researchers will conduct separate analyses of the selected participant (i.e., the individual who met the eligibility criteria) and other members of that participant's household. This will test whether there are any spillover effects of the intervention to other people in the household. For clarity in this record, any discussion of sample size and participants refers to households, as this is the primary level for participant selection and assignment.
Interventions
BEHAVIORALPersonal testimonial
Participants will receive a letter promoting a plant-based diet. This letter will feature a personal testimonial about the benefits of a plant-based diet. Presenting this information to participants might encourage them to make behavioral changes to improve their health.
BEHAVIORALForks Over Knives Documentary
Participants will be mailed the documentary Forks Over Knives, which provides scientific arguments promoting a plant-based and whole foods diet. The behavioral effect of this documentary comes from watching the documentary and potentially choosing to order a free cookbook (participants are given this opportunity in the letter accompanying the documentary). The effect of the diet itself is not a central part of the intervention, as people can choose to adopt or not adopt any part of the diet.
BEHAVIORALCommitment nudge
At the end of the letter promoting a plant-based diet, participants will be asked to write dates and personal signatures committing to watching the documentary. They will be asked to mail back this written commitment. Stating one's intentions to implement certain behavior is meant to increase the likelihood of follow-up behavior. This request might nudge more people to watch the documentary and make some behavioral changes to prevent negative health outcomes.
BEHAVIORALPrevention nudge
As part of the letter promoting a plant-based diet, one paragraph will describe the risks of not taking action. This phrasing reframes the status quo as contributing to future loss (e.g., costs of medication and operations). In effect, the letter encourages participants to focus on preventing this loss by taking action. This additional text might nudge more people to watch the documentary and make some behavioral changes to prevent negative health outcomes.
Sponsors
Geisinger Clinic
Study design
Allocation
RANDOMIZED
Intervention model
FACTORIAL
Primary purpose
SUPPORTIVE_CARE
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)
Masking description
Participants, care providers, and outcomes assessors will not know the participant's arm. Insurance claims data and medical health records will be used (after all identifying information is removed).
Intervention model description
One group of participants will not be contacted at all (n = 6200). One group will only received a letter promoting a plant-based diet (n = 2200). Twelve groups (n = 550 for each group) will receive the letter promoting a plant-based diet, along with the Forks Over Knives documentary. The documentary will be delivered through 3 different methods, and the accompanying letter will contain 4 different combinations of behavioral nudges. * 1 primary control group (no contact) * 1 group contacted by letter * 3 groups (documentary distribution: online link, DVD, online link + DVD) x 4 groups (behavioral nudges in the letter: no nudge, commitment nudge, prevention nudge, commitment and prevention nudges) Note: The control group size is an estimate of number of participants who match the eligibility criteria but were not randomly assigned to an experimental group.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Has two out of the three following conditions: * Body mass index over 30 * Diagnosis of type 2 diabetes (specifically with at least one medication) * Diagnosis of cardiovascular disease * Has health insurance through Geisinger Health Plan (is an active member with a full 12-month enrollment in the previous year) under one of the following categories: * Medicare with required primary care provider * Medicaid * Individual policy under the Affordable Care Act * Has visited their primary care provider in the past 12 months
Exclusion criteria
* Is institutionalized * Has active cancer, cirrhosis, renal failure, dementia, or active psychosis * Is in the same household as another selected participant
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2 years | Total annual amount of medical and pharmacy costs (sum) as reported by Geisinger Health Plan. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Lower costs is the desirable outcome. |
| Number of Visits From One Year Before to One Year After Intervention | 2 years | Total number of primary care physician and specialist visits (sum) as reported by Geisinger Health Plan. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Fewer visits is the desirable outcome. |
| Number of Prescriptions From One Year Before to One Year After Intervention | 2 years | Total number of prescriptions (fills) as reported by Geisinger Health Plan. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Fewer prescriptions is the desirable outcome. |
| Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2 years | Total number of unique prescribed medication in the past year as reported by Geisinger Health Plan. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Less unique prescribed medication is the desirable outcome. |
| Body Mass Index From One Year Before to One Year After Intervention | 2 years | Taken from annual checkup with primary care provider. Computed from height (in meters) and weight (in kilograms) data with the formula kilograms/meters\^2. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. A body mass index between the range of 18.5 to 25 is the desirable outcome. |
| Systolic Blood Pressure From One Year Before to One Year After Intervention | 2 years | Taken from annual checkup with primary care provider. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Systolic blood pressure that is 120 millimeters of mercury (mmHg) or less is the desirable outcome. |
| Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2 years | Taken from annual checkup with primary care provider. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Systolic blood pressure that is 80 millimeters of mercury (mmHg) or less is the desirable outcome. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Triglyceride Levels From One Year Before to One Year After Intervention | 2 years | One component of cholesterol, used if data is on health record. A triglyceride level of 150 milligrams per deciliter (mg/dl) or lower is the desirable outcome. |
| Low-density Lipoprotein (LDL) Levels From One Year Before to One Year After Intervention | 2 years | One component of cholesterol, used if data is on health record. An LDL level of 100 milligrams per deciliter (mg/dl) or lower is the desirable outcome. |
| Five Years Before to Two Years After Intervention in Depressed Mood and Anhedonia as Assessed by the Patient Health Questionnaire-2 (PHQ-2) (Extended Time Frame) | 7 years | Assesses depressed mood and anhedonia in the past two weeks; used if data is on health record. The sum of two items (each scored 0-3) is computed with a total score range of 0-6. A lower score is the desired outcome. |
| Hemoglobin A1c (hbA1c) From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | Test for diabetes, used if data is on health record. Percentage score reflects blood-glucose levels. An hbA1c level of 5.7% and below is the desirable outcome. |
| Low-density Lipoprotein/High-density Lipoprotein (LDL/HDL) Ratios From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | Computed as the ratio of LDL/HDL. An LDL/HDL ratio of 3 or less for men and 2.5 or less for women is the desirable outcome. |
| High-density Lipoprotein (HDL) Levels From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | One component of cholesterol, used if data is on health record. An HDL level of 60 milligrams per deciliter (mg/dl) or higher is the desirable outcome. |
| Low-density Lipoprotein (LDL) Levels From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | One component of cholesterol, used if data is on health record. An LDL level of 100 milligrams per deciliter (mg/dl) or lower is the desirable outcome. |
| Triglyceride Levels From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | One component of cholesterol, used if data is on health record. A triglyceride level of 150 milligrams per deciliter (mg/dl) or lower is the desirable outcome. |
| Diastolic Blood Pressure From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | Taken from annual checkup with primary care provider. Systolic blood pressure that is 80 millimeters of mercury (mmHg) or less is the desirable outcome. |
| Systolic Blood Pressure From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | Taken from annual checkup with primary care provider. Systolic blood pressure that is 120 millimeters of mercury (mmHg) or less is the desirable outcome. |
| Body Mass Index From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | Taken from annual checkup with primary care provider. Computed from height (in meters) and weight (in kilograms) data with the formula kilograms/meters\^2. A body mass index between the range of 18.5 to 25 is the desirable outcome. |
| Number of Unique Prescribed Medication From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | Total number of unique prescribed medication in the past year as reported by Geisinger Health Plan. Less unique prescribed medication is the desirable outcome. |
| Number of Prescriptions From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | Total number of prescriptions (standard unit is prescription per number of days supplied) as reported by Geisinger Health Plan. Fewer prescriptions is the desirable outcome. |
| Number of Visits From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | Total number of primary care physician and specialist visits (sum) as reported by Geisinger Health Plan. Fewer visits is the desirable outcome. |
| Medical Cost in US Dollars From Five Years Before to Two Years After Intervention (Extended Time Frame) | 7 years | Total annual amount of medical and pharmacy costs (sum) as reported by Geisinger Health Plan. Lower costs is the desirable outcome. |
| Values From One Year Before to One Year After Intervention of Depressed Mood and Anhedonia as Assessed by the Patient Health Questionnaire-2 (PHQ-2) | 2 years | Although originally listed as secondary, this outcome measure was intended to be exploratory. Due to the largely null pattern of results on the primary outcomes, it was decided to forgo additional analysis at this time. |
| Hemoglobin A1c (hbA1c) From One Year Before to One Year After Intervention | 2 years | Test for diabetes, used if data is on health record. Percentage score reflects blood-glucose levels. An hbA1c level of 5.7% or lower is the desirable outcome. |
| Low-density Lipoprotein/High-density Lipoprotein (LDL/HDL) Ratios From One Year Before to One Year After Intervention | 2 years | Computed as the ratio of LDL/HDL. An LDL/HDL ratio of 3 or less for men and 2.5 or less for women is the desirable outcome. |
| High-density Lipoprotein (HDL) Levels From One Year Before to One Year After Intervention | 2 years | One component of cholesterol, used if data is on health record. An HDL level of 60 milligrams per deciliter (mg/dl) or higher is the desirable outcome. |
Countries
United States
Participant flow
Recruitment details
The list of eligible participants was randomized before mail was sent (or not sent for no contact control group).
Participants by arm
| Arm | Count |
|---|---|
| No Contact Control Participants were not contacted. | 2,434 |
| Letter Participants were only contacted through a letter with a personal testimonial. | 2,200 |
| Link and no Nudge Participants were sent the Forks Over Knives documentary online link and a letter with a personal testimonial and no nudges. | 550 |
| Link and Commitment Nudge Participants were sent the Forks Over Knives documentary online link and a letter with a personal testimonial and a commitment nudge. | 550 |
| Link and Prevention Nudge Participants were sent the Forks Over Knives documentary online link and a letter with a personal testimonial and a prevention nudge. | 550 |
| Link and Both Nudges Participants were sent the Forks Over Knives documentary online link and a letter with a personal testimonial and both commitment and prevention nudges. | 550 |
| DVD and no Nudge Participants were sent the Forks Over Knives documentary DVD and a letter with a personal testimonial and no behavioral nudges. | 550 |
| DVD and Commitment Nudge Participants were sent the Forks Over Knives documentary DVD and a letter with a personal testimonial and a commitment nudge. | 550 |
| DVD and Prevention Nudge Participants were sent the Forks Over Knives documentary DVD and a letter with a personal testimonial and a prevention nudge. | 550 |
| DVD and Both Nudges Participants were sent the Forks Over Knives documentary DVD and a letter with a personal testimonial and both commitment and prevention nudges. | 550 |
| Link and DVD and no Nudge Participants were sent the Forks Over Knives documentary online link and DVD and a letter with a personal testimonial and no behavioral nudges. | 550 |
| Link and DVD and Commitment Nudge Participants were sent the Forks Over Knives documentary online link and DVD and a letter with a personal testimonial and a commitment nudge. | 550 |
| Link and DVD and Prevention Nudge Participants were sent the Forks Over Knives documentary online link and DVD and a letter with a personal testimonial and a prevention nudge. | 550 |
| Link and DVD and Both Nudges Participants were sent the Forks Over Knives documentary online link and DVD and a letter with a personal testimonial and both commitment and prevention nudges. | 550 |
| Total | 11,234 |
Baseline characteristics
| Characteristic | Total | Link and DVD and Prevention Nudge | Link and DVD and Both Nudges | No Contact Control | Letter | Link and no Nudge | Link and Commitment Nudge | Link and Prevention Nudge | Link and Both Nudges | DVD and no Nudge | DVD and Commitment Nudge | DVD and Prevention Nudge | DVD and Both Nudges | Link and DVD and no Nudge | Link and DVD and Commitment Nudge |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Age, Categorical >=65 years | 0 Participants | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Age, Categorical Between 18 and 65 years | 0 Participants | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Race and Ethnicity Not Collected | 0 Participants | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Region of Enrollment United States | 11234 participants | 550 participants | 550 participants | 2434 participants | 2200 participants | 550 participants | 550 participants | 550 participants | 550 participants | 550 participants | 550 participants | 550 participants | 550 participants | 550 participants | 550 participants |
| Sex: Female, Male Female | 0 Participants | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Sex: Female, Male Male | 0 Participants | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk | EG003 affected / at risk | EG004 affected / at risk | EG005 affected / at risk | EG006 affected / at risk | EG007 affected / at risk | EG008 affected / at risk | EG009 affected / at risk | EG010 affected / at risk | EG011 affected / at risk | EG012 affected / at risk | EG013 affected / at risk |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 |
| other Total, other adverse events | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 |
| serious Total, serious adverse events | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 | 0 / 0 |
Outcome results
Primary
Body Mass Index From One Year Before to One Year After Intervention
Taken from annual checkup with primary care provider. Computed from height (in meters) and weight (in kilograms) data with the formula kilograms/meters\^2. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. A body mass index between the range of 18.5 to 25 is the desirable outcome.
Time frame: 2 years
Population: Number of participants analyzed was based on the number of baseline (2019) records with no missing data for this outcome.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| No Contact Control | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 36.44 kg/m^2 | Standard Deviation 7.35 |
| No Contact Control | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 36.06 kg/m^2 | Standard Deviation 7.44 |
| Letter | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 36.48 kg/m^2 | Standard Deviation 7.72 |
| Letter | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 36.05 kg/m^2 | Standard Deviation 7.61 |
| Link and no Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 36.46 kg/m^2 | Standard Deviation 7.53 |
| Link and no Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 36.16 kg/m^2 | Standard Deviation 7.67 |
| Link and Commitment Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 36.20 kg/m^2 | Standard Deviation 7.81 |
| Link and Commitment Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 36.18 kg/m^2 | Standard Deviation 8.11 |
| Link and Prevention Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 36.77 kg/m^2 | Standard Deviation 7.72 |
| Link and Prevention Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 37.26 kg/m^2 | Standard Deviation 7.59 |
| Link and Both Nudges | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 36.19 kg/m^2 | Standard Deviation 7.63 |
| Link and Both Nudges | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 36.58 kg/m^2 | Standard Deviation 7.67 |
| DVD and no Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 36.83 kg/m^2 | Standard Deviation 8.76 |
| DVD and no Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 36.39 kg/m^2 | Standard Deviation 8.42 |
| DVD and Commitment Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 36.56 kg/m^2 | Standard Deviation 7.93 |
| DVD and Commitment Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 35.96 kg/m^2 | Standard Deviation 7.58 |
| DVD and Prevention Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 36.11 kg/m^2 | Standard Deviation 7.72 |
| DVD and Prevention Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 36.48 kg/m^2 | Standard Deviation 7.33 |
| DVD and Both Nudges | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 36.77 kg/m^2 | Standard Deviation 8.8 |
| DVD and Both Nudges | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 37.00 kg/m^2 | Standard Deviation 8.16 |
| Link and DVD and no Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 35.73 kg/m^2 | Standard Deviation 7.66 |
| Link and DVD and no Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 36.12 kg/m^2 | Standard Deviation 7.67 |
| Link and DVD and Commitment Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 36.42 kg/m^2 | Standard Deviation 8.08 |
| Link and DVD and Commitment Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 36.83 kg/m^2 | Standard Deviation 7.87 |
| Link and DVD and Prevention Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 36.68 kg/m^2 | Standard Deviation 7.8 |
| Link and DVD and Prevention Nudge | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 36.30 kg/m^2 | Standard Deviation 7.92 |
| Link and DVD and Both Nudges | Body Mass Index From One Year Before to One Year After Intervention | 2020 | 35.30 kg/m^2 | Standard Deviation 7.05 |
| Link and DVD and Both Nudges | Body Mass Index From One Year Before to One Year After Intervention | 2019 | 35.76 kg/m^2 | Standard Deviation 7.05 |
Comparison: In this contrast, letter was compared against all other conditions (coded into one category and set as the reference group). The key outcome is the interaction between conditions and time (2019 as the reference group).p-value: 0.391Regression, Linear
Comparison: In this contrast, no contact control was compared against all other conditions (coded into one category and set as the reference group). The key outcome is the interaction between conditions and time (2019 as the reference group).p-value: 0.861Regression, Linear
Comparison: In this contrast, prevention conditions (coded into one category) were compared against no nudge conditions (coded into one category and set as the reference group).p-value: 0.835Regression, Linear
Comparison: In this contrast, commitment conditions (coded into one category) were compared against no nudge conditions (coded into one category and set as the reference group).p-value: 0.877Regression, Linear
Comparison: In this contrast, both nudge conditions (coded into one category) were compared against no nudge conditions (coded into one category and set as the reference group).p-value: 0.969Regression, Logistic
Comparison: In this contrast, no nudge conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.893Regression, Linear
Comparison: In this contrast, In this contrast, prevention conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.689Regression, Linear
Comparison: In this contrast, commitment conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.427Regression, Linear
Comparison: In this contrast, both nudge conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.504Regression, Linear
Comparison: In this contrast, no nudge conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.893Regression, Linear
Comparison: In this contrast, prevention conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.918Regression, Linear
Comparison: In this contrast, commitment conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.755Regression, Linear
Comparison: In this contrast, both nudge conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.858Regression, Linear
Primary
Diastolic Blood Pressure From One Year Before to One Year After Intervention
Taken from annual checkup with primary care provider. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Systolic blood pressure that is 80 millimeters of mercury (mmHg) or less is the desirable outcome.
Time frame: 2 years
Population: Number of participants analyzed was based on the number of baseline (2019) records with no missing data for this outcome.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| No Contact Control | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 72.91 mmHg | Standard Deviation 10.99 |
| No Contact Control | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 72.48 mmHg | Standard Deviation 11.07 |
| Letter | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 72.79 mmHg | Standard Deviation 10.91 |
| Letter | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 72.90 mmHg | Standard Deviation 11.42 |
| Link and no Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 72.95 mmHg | Standard Deviation 10.89 |
| Link and no Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 73.07 mmHg | Standard Deviation 10.96 |
| Link and Commitment Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 73.48 mmHg | Standard Deviation 10.09 |
| Link and Commitment Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 73.10 mmHg | Standard Deviation 11.85 |
| Link and Prevention Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 72.41 mmHg | Standard Deviation 10.85 |
| Link and Prevention Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 72.93 mmHg | Standard Deviation 10.9 |
| Link and Both Nudges | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 72.65 mmHg | Standard Deviation 11.28 |
| Link and Both Nudges | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 72.27 mmHg | Standard Deviation 10.4 |
| DVD and no Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 72.57 mmHg | Standard Deviation 10.37 |
| DVD and no Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 72.42 mmHg | Standard Deviation 11.38 |
| DVD and Commitment Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 72.44 mmHg | Standard Deviation 11.13 |
| DVD and Commitment Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 72.77 mmHg | Standard Deviation 11.12 |
| DVD and Prevention Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 72.64 mmHg | Standard Deviation 11.34 |
| DVD and Prevention Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 72.80 mmHg | Standard Deviation 10.51 |
| DVD and Both Nudges | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 73.88 mmHg | Standard Deviation 11.2 |
| DVD and Both Nudges | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 73.44 mmHg | Standard Deviation 10.78 |
| Link and DVD and no Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 72.97 mmHg | Standard Deviation 10.79 |
| Link and DVD and no Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 73.26 mmHg | Standard Deviation 10.41 |
| Link and DVD and Commitment Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 72.47 mmHg | Standard Deviation 10.64 |
| Link and DVD and Commitment Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 73.21 mmHg | Standard Deviation 10.51 |
| Link and DVD and Prevention Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 73.11 mmHg | Standard Deviation 10.79 |
| Link and DVD and Prevention Nudge | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 72.58 mmHg | Standard Deviation 10.79 |
| Link and DVD and Both Nudges | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 72.79 mmHg | Standard Deviation 11.37 |
| Link and DVD and Both Nudges | Diastolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 73.04 mmHg | Standard Deviation 10.68 |
Comparison: In this contrast, letter was compared against all other conditions (coded into one category and set as the reference group). The key outcome is the interaction between conditions and time (2019 as the reference group).p-value: 0.357Regression, Linear
Comparison: In this contrast, no contact control was compared against all other conditions (coded into one category and set as the reference group). The key outcome is the interaction between conditions and time (2019 as the reference group).p-value: 0.294Regression, Linear
Comparison: In this contrast, prevention conditions (coded into one category) were compared against no nudge conditions (coded into one category and set as the reference group).p-value: 0.496Regression, Linear
Comparison: In this contrast, commitment conditions (coded into one category) were compared against no nudge conditions (coded into one category and set as the reference group).p-value: 0.722Regression, Linear
Comparison: In this contrast, both nudge conditions (coded into one category) were compared against no nudge conditions (coded into one category and set as the reference group).p-value: 0.445Regression, Linear
Comparison: In this contrast, no nudge conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.531Regression, Linear
Comparison: In this contrast, prevention conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.177Regression, Linear
Comparison: In this contrast, commitment conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.314Regression, Linear
Comparison: In this contrast, both nudge conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.85Regression, Linear
Comparison: In this contrast, no nudge conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.391Regression, Linear
Comparison: In this contrast, prevention conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.906Regression, Linear
Comparison: In this contrast, commitment conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.635Regression, Linear
Comparison: In this contrast, both nudge conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.093Regression, Linear
Primary
Medical Cost in US Dollars From One Year Before to One Year After Intervention
Total annual amount of medical and pharmacy costs (sum) as reported by Geisinger Health Plan. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Lower costs is the desirable outcome.
Time frame: 2 years
Population: Number of participants analyzed was based on the number of baseline (2019) records with no missing data for this outcome.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| No Contact Control | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 6123.39 dollars | Standard Deviation 9447.33 |
| No Contact Control | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 6101.54 dollars | Standard Deviation 10076.51 |
| Letter | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 5863.82 dollars | Standard Deviation 11818.81 |
| Letter | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 6309.49 dollars | Standard Deviation 13727.9 |
| Link and no Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 5901.99 dollars | Standard Deviation 11124.11 |
| Link and no Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 5754.70 dollars | Standard Deviation 11157.93 |
| Link and Commitment Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 5630.26 dollars | Standard Deviation 7461.85 |
| Link and Commitment Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 5932.12 dollars | Standard Deviation 8279.96 |
| Link and Prevention Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 6078.06 dollars | Standard Deviation 9847.06 |
| Link and Prevention Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 6427.50 dollars | Standard Deviation 9412.89 |
| Link and Both Nudges | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 7047.98 dollars | Standard Deviation 14827.87 |
| Link and Both Nudges | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 6343.24 dollars | Standard Deviation 9206.43 |
| DVD and no Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 6270.08 dollars | Standard Deviation 9647.26 |
| DVD and no Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 6284.85 dollars | Standard Deviation 10203.78 |
| DVD and Commitment Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 6336.36 dollars | Standard Deviation 9452.46 |
| DVD and Commitment Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 6772.89 dollars | Standard Deviation 10159.36 |
| DVD and Prevention Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 6709.80 dollars | Standard Deviation 14548.68 |
| DVD and Prevention Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 6129.37 dollars | Standard Deviation 10795.32 |
| DVD and Both Nudges | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 5753.38 dollars | Standard Deviation 7720.93 |
| DVD and Both Nudges | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 5542.03 dollars | Standard Deviation 7632.87 |
| Link and DVD and no Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 6723.81 dollars | Standard Deviation 13785.71 |
| Link and DVD and no Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 6681.14 dollars | Standard Deviation 10538.91 |
| Link and DVD and Commitment Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 6795.82 dollars | Standard Deviation 12895.57 |
| Link and DVD and Commitment Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 6850.98 dollars | Standard Deviation 11812.93 |
| Link and DVD and Prevention Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 6202.43 dollars | Standard Deviation 8509.4 |
| Link and DVD and Prevention Nudge | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 6275.88 dollars | Standard Deviation 9067.47 |
| Link and DVD and Both Nudges | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2020 | 5260.87 dollars | Standard Deviation 6808.98 |
| Link and DVD and Both Nudges | Medical Cost in US Dollars From One Year Before to One Year After Intervention | 2019 | 5305.93 dollars | Standard Deviation 6743.15 |
Primary
Number of Prescriptions From One Year Before to One Year After Intervention
Total number of prescriptions (fills) as reported by Geisinger Health Plan. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Fewer prescriptions is the desirable outcome.
Time frame: 2 years
Population: Number of participants analyzed was based on the number of baseline (2019) records with no missing data for this outcome.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| No Contact Control | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 48.96 prescriptions | Standard Deviation 49.89 |
| No Contact Control | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 29.87 prescriptions | Standard Deviation 47.45 |
| Letter | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 48.02 prescriptions | Standard Deviation 48.47 |
| Letter | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 26.82 prescriptions | Standard Deviation 31.06 |
| Link and no Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 47.44 prescriptions | Standard Deviation 49.7 |
| Link and no Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 29.09 prescriptions | Standard Deviation 62.85 |
| Link and Commitment Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 50.85 prescriptions | Standard Deviation 46.95 |
| Link and Commitment Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 29.86 prescriptions | Standard Deviation 32.26 |
| Link and Prevention Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 29.32 prescriptions | Standard Deviation 33 |
| Link and Prevention Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 50.50 prescriptions | Standard Deviation 46.08 |
| Link and Both Nudges | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 30.35 prescriptions | Standard Deviation 32.78 |
| Link and Both Nudges | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 49.66 prescriptions | Standard Deviation 43.44 |
| DVD and no Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 49.14 prescriptions | Standard Deviation 54.8 |
| DVD and no Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 28.05 prescriptions | Standard Deviation 32.78 |
| DVD and Commitment Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 52.71 prescriptions | Standard Deviation 53.75 |
| DVD and Commitment Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 30.24 prescriptions | Standard Deviation 51.07 |
| DVD and Prevention Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 30.32 prescriptions | Standard Deviation 35.34 |
| DVD and Prevention Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 48.66 prescriptions | Standard Deviation 43.52 |
| DVD and Both Nudges | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 31.70 prescriptions | Standard Deviation 34.24 |
| DVD and Both Nudges | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 49.34 prescriptions | Standard Deviation 48.53 |
| Link and DVD and no Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 29.83 prescriptions | Standard Deviation 36.16 |
| Link and DVD and no Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 48.82 prescriptions | Standard Deviation 51.3 |
| Link and DVD and Commitment Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 27.83 prescriptions | Standard Deviation 29.2 |
| Link and DVD and Commitment Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 50.02 prescriptions | Standard Deviation 49.1 |
| Link and DVD and Prevention Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 50.26 prescriptions | Standard Deviation 49.83 |
| Link and DVD and Prevention Nudge | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 31.69 prescriptions | Standard Deviation 36.72 |
| Link and DVD and Both Nudges | Number of Prescriptions From One Year Before to One Year After Intervention | 2020 | 27.30 prescriptions | Standard Deviation 32.97 |
| Link and DVD and Both Nudges | Number of Prescriptions From One Year Before to One Year After Intervention | 2019 | 43.81 prescriptions | Standard Deviation 44.03 |
Primary
Number of Unique Prescribed Medication From One Year Before to One Year After Intervention
Total number of unique prescribed medication in the past year as reported by Geisinger Health Plan. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Less unique prescribed medication is the desirable outcome.
Time frame: 2 years
Population: Number of participants analyzed was based on the number of baseline (2019) records with no missing data for this outcome.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| No Contact Control | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 8.12 prescriptions | Standard Deviation 6.08 |
| No Contact Control | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 5.92 prescriptions | Standard Deviation 4.86 |
| Letter | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 8.15 prescriptions | Standard Deviation 6.22 |
| Letter | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 5.82 prescriptions | Standard Deviation 5.05 |
| Link and no Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 7.90 prescriptions | Standard Deviation 6.08 |
| Link and no Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 5.80 prescriptions | Standard Deviation 4.93 |
| Link and Commitment Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 8.50 prescriptions | Standard Deviation 6.25 |
| Link and Commitment Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 6.27 prescriptions | Standard Deviation 5.28 |
| Link and Prevention Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 6.00 prescriptions | Standard Deviation 5.31 |
| Link and Prevention Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 8.47 prescriptions | Standard Deviation 6.29 |
| Link and Both Nudges | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 6.28 prescriptions | Standard Deviation 5.36 |
| Link and Both Nudges | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 8.48 prescriptions | Standard Deviation 5.76 |
| DVD and no Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 7.84 prescriptions | Standard Deviation 6.18 |
| DVD and no Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 5.70 prescriptions | Standard Deviation 4.77 |
| DVD and Commitment Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 8.77 prescriptions | Standard Deviation 7.52 |
| DVD and Commitment Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 5.98 prescriptions | Standard Deviation 6.18 |
| DVD and Prevention Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 6.13 prescriptions | Standard Deviation 5.43 |
| DVD and Prevention Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 8.32 prescriptions | Standard Deviation 6.11 |
| DVD and Both Nudges | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 6.44 prescriptions | Standard Deviation 5.99 |
| DVD and Both Nudges | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 8.39 prescriptions | Standard Deviation 7.07 |
| Link and DVD and no Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 6.28 prescriptions | Standard Deviation 5.28 |
| Link and DVD and no Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 8.25 prescriptions | Standard Deviation 6.17 |
| Link and DVD and Commitment Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 5.88 prescriptions | Standard Deviation 4.68 |
| Link and DVD and Commitment Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 8.45 prescriptions | Standard Deviation 6.43 |
| Link and DVD and Prevention Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 8.53 prescriptions | Standard Deviation 6.63 |
| Link and DVD and Prevention Nudge | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 6.39 prescriptions | Standard Deviation 5.47 |
| Link and DVD and Both Nudges | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2020 | 5.66 prescriptions | Standard Deviation 4.96 |
| Link and DVD and Both Nudges | Number of Unique Prescribed Medication From One Year Before to One Year After Intervention | 2019 | 7.50 prescriptions | Standard Deviation 6.15 |
Primary
Number of Visits From One Year Before to One Year After Intervention
Total number of primary care physician and specialist visits (sum) as reported by Geisinger Health Plan. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Fewer visits is the desirable outcome.
Time frame: 2 years
Population: Number of participants analyzed was based on the number of baseline (2019) records with no missing data for this outcome.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| No Contact Control | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.59 visits | Standard Deviation 6.31 |
| No Contact Control | Number of Visits From One Year Before to One Year After Intervention | 2020 | 4.77 visits | Standard Deviation 5.65 |
| Letter | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.57 visits | Standard Deviation 6.12 |
| Letter | Number of Visits From One Year Before to One Year After Intervention | 2020 | 4.80 visits | Standard Deviation 5.56 |
| Link and no Nudge | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.17 visits | Standard Deviation 5.91 |
| Link and no Nudge | Number of Visits From One Year Before to One Year After Intervention | 2020 | 4.26 visits | Standard Deviation 5.3 |
| Link and Commitment Nudge | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.66 visits | Standard Deviation 6.76 |
| Link and Commitment Nudge | Number of Visits From One Year Before to One Year After Intervention | 2020 | 4.88 visits | Standard Deviation 5.78 |
| Link and Prevention Nudge | Number of Visits From One Year Before to One Year After Intervention | 2020 | 4.89 visits | Standard Deviation 5.52 |
| Link and Prevention Nudge | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.69 visits | Standard Deviation 6.12 |
| Link and Both Nudges | Number of Visits From One Year Before to One Year After Intervention | 2020 | 5.13 visits | Standard Deviation 5.36 |
| Link and Both Nudges | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.77 visits | Standard Deviation 5.84 |
| DVD and no Nudge | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.69 visits | Standard Deviation 5.49 |
| DVD and no Nudge | Number of Visits From One Year Before to One Year After Intervention | 2020 | 4.82 visits | Standard Deviation 5.29 |
| DVD and Commitment Nudge | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.43 visits | Standard Deviation 6.08 |
| DVD and Commitment Nudge | Number of Visits From One Year Before to One Year After Intervention | 2020 | 4.51 visits | Standard Deviation 5.31 |
| DVD and Prevention Nudge | Number of Visits From One Year Before to One Year After Intervention | 2020 | 4.49 visits | Standard Deviation 5.49 |
| DVD and Prevention Nudge | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.60 visits | Standard Deviation 6.74 |
| DVD and Both Nudges | Number of Visits From One Year Before to One Year After Intervention | 2020 | 5.27 visits | Standard Deviation 5.8 |
| DVD and Both Nudges | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.88 visits | Standard Deviation 6.13 |
| Link and DVD and no Nudge | Number of Visits From One Year Before to One Year After Intervention | 2020 | 5.15 visits | Standard Deviation 5.85 |
| Link and DVD and no Nudge | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.71 visits | Standard Deviation 6.25 |
| Link and DVD and Commitment Nudge | Number of Visits From One Year Before to One Year After Intervention | 2020 | 4.69 visits | Standard Deviation 6.24 |
| Link and DVD and Commitment Nudge | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.59 visits | Standard Deviation 7.87 |
| Link and DVD and Prevention Nudge | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.53 visits | Standard Deviation 5.89 |
| Link and DVD and Prevention Nudge | Number of Visits From One Year Before to One Year After Intervention | 2020 | 4.63 visits | Standard Deviation 5.18 |
| Link and DVD and Both Nudges | Number of Visits From One Year Before to One Year After Intervention | 2020 | 4.34 visits | Standard Deviation 5.06 |
| Link and DVD and Both Nudges | Number of Visits From One Year Before to One Year After Intervention | 2019 | 5.26 visits | Standard Deviation 6.15 |
Primary
Systolic Blood Pressure From One Year Before to One Year After Intervention
Taken from annual checkup with primary care provider. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Systolic blood pressure that is 120 millimeters of mercury (mmHg) or less is the desirable outcome.
Time frame: 2 years
Population: Number of participants analyzed was based on the number of baseline (2019) records with no missing data for this outcome.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| No Contact Control | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 130.00 mmHg | Standard Deviation 17.57 |
| No Contact Control | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 129.50 mmHg | Standard Deviation 17.94 |
| Letter | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 129.88 mmHg | Standard Deviation 17.19 |
| Letter | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 129.97 mmHg | Standard Deviation 18.31 |
| Link and no Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 130.47 mmHg | Standard Deviation 17.97 |
| Link and no Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 130.57 mmHg | Standard Deviation 17 |
| Link and Commitment Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 131.4 mmHg | Standard Deviation 16.59 |
| Link and Commitment Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 130.26 mmHg | Standard Deviation 19.08 |
| Link and Prevention Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 129.91 mmHg | Standard Deviation 17.03 |
| Link and Prevention Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 130.72 mmHg | Standard Deviation 17.33 |
| Link and Both Nudges | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 129.73 mmHg | Standard Deviation 18.17 |
| Link and Both Nudges | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 129.27 mmHg | Standard Deviation 17.18 |
| DVD and no Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 129.88 mmHg | Standard Deviation 16.97 |
| DVD and no Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 129.53 mmHg | Standard Deviation 17.33 |
| DVD and Commitment Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 127.98 mmHg | Standard Deviation 18.5 |
| DVD and Commitment Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 127.58 mmHg | Standard Deviation 18.13 |
| DVD and Prevention Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 129.37 mmHg | Standard Deviation 17.2 |
| DVD and Prevention Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 129.19 mmHg | Standard Deviation 17.03 |
| DVD and Both Nudges | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 131.79 mmHg | Standard Deviation 17.33 |
| DVD and Both Nudges | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 131.46 mmHg | Standard Deviation 16.85 |
| Link and DVD and no Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 129.63 mmHg | Standard Deviation 17.55 |
| Link and DVD and no Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 130.41 mmHg | Standard Deviation 17.32 |
| Link and DVD and Commitment Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 129.25 mmHg | Standard Deviation 18.01 |
| Link and DVD and Commitment Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 129.59 mmHg | Standard Deviation 17.1 |
| Link and DVD and Prevention Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 130.39 mmHg | Standard Deviation 17.17 |
| Link and DVD and Prevention Nudge | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 129.90 mmHg | Standard Deviation 17.29 |
| Link and DVD and Both Nudges | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2020 | 129.70 mmHg | Standard Deviation 17.67 |
| Link and DVD and Both Nudges | Systolic Blood Pressure From One Year Before to One Year After Intervention | 2019 | 129.29 mmHg | Standard Deviation 17.9 |
Comparison: In this contrast, letter was compared against all other conditions (coded into one category and set as the reference group). The key outcome is the interaction between conditions and time (2019 as the reference group).p-value: 0.436Regression, Linear
Comparison: In this contrast, no contact control was compared against all other conditions (coded into one category and set as the reference group). The key outcome is the interaction between conditions and time (2019 as the reference group).p-value: 0.539Regression, Linear
Comparison: In this contrast, prevention conditions (coded into one category) were compared against no nudge conditions (coded into one category and set as the reference group).p-value: 0.994Regression, Linear
Comparison: In this contrast, commitment conditions (coded into one category) were compared against no nudge conditions (coded into one category and set as the reference group).p-value: 0.7Regression, Linear
Comparison: In this contrast, both nudge conditions (coded into one category) were compared against no nudge conditions (coded into one category and set as the reference group).p-value: 0.258Regression, Logistic
Comparison: In this contrast, no nudge conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.428Regression, Linear
Comparison: In this contrast, prevention conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.434Regression, Linear
Comparison: In this contrast, commitment conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.228Regression, Linear
Comparison: In this contrast, both nudge conditions (coded into one category) were compared against the letter condition (set as the reference group).p-value: 0.674Regression, Linear
Comparison: In this contrast, no nudge conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.799Regression, Linear
Comparison: In this contrast, prevention conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.794Regression, Linear
Comparison: In this contrast, commitment conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.871Regression, Linear
Comparison: In this contrast, both nudge conditions (coded into one category) were compared against the no contact condition (set as the reference group).p-value: 0.139Regression, Linear
Secondary
Body Mass Index From Five Years Before to Two Years After Intervention (Extended Time Frame)
Taken from annual checkup with primary care provider. Computed from height (in meters) and weight (in kilograms) data with the formula kilograms/meters\^2. A body mass index between the range of 18.5 to 25 is the desirable outcome.
Time frame: 7 years
Secondary
Diastolic Blood Pressure From Five Years Before to Two Years After Intervention (Extended Time Frame)
Taken from annual checkup with primary care provider. Systolic blood pressure that is 80 millimeters of mercury (mmHg) or less is the desirable outcome.
Time frame: 7 years
Secondary
Five Years Before to Two Years After Intervention in Depressed Mood and Anhedonia as Assessed by the Patient Health Questionnaire-2 (PHQ-2) (Extended Time Frame)
Assesses depressed mood and anhedonia in the past two weeks; used if data is on health record. The sum of two items (each scored 0-3) is computed with a total score range of 0-6. A lower score is the desired outcome.
Time frame: 7 years
Secondary
Hemoglobin A1c (hbA1c) From Five Years Before to Two Years After Intervention (Extended Time Frame)
Test for diabetes, used if data is on health record. Percentage score reflects blood-glucose levels. An hbA1c level of 5.7% and below is the desirable outcome.
Time frame: 7 years
Secondary
Hemoglobin A1c (hbA1c) From One Year Before to One Year After Intervention
Test for diabetes, used if data is on health record. Percentage score reflects blood-glucose levels. An hbA1c level of 5.7% or lower is the desirable outcome.
Time frame: 2 years
Secondary
High-density Lipoprotein (HDL) Levels From Five Years Before to Two Years After Intervention (Extended Time Frame)
One component of cholesterol, used if data is on health record. An HDL level of 60 milligrams per deciliter (mg/dl) or higher is the desirable outcome.
Time frame: 7 years
Secondary
High-density Lipoprotein (HDL) Levels From One Year Before to One Year After Intervention
One component of cholesterol, used if data is on health record. An HDL level of 60 milligrams per deciliter (mg/dl) or higher is the desirable outcome.
Time frame: 2 years
Secondary
Low-density Lipoprotein/High-density Lipoprotein (LDL/HDL) Ratios From Five Years Before to Two Years After Intervention (Extended Time Frame)
Computed as the ratio of LDL/HDL. An LDL/HDL ratio of 3 or less for men and 2.5 or less for women is the desirable outcome.
Time frame: 7 years
Secondary
Low-density Lipoprotein/High-density Lipoprotein (LDL/HDL) Ratios From One Year Before to One Year After Intervention
Computed as the ratio of LDL/HDL. An LDL/HDL ratio of 3 or less for men and 2.5 or less for women is the desirable outcome.
Time frame: 2 years
Secondary
Low-density Lipoprotein (LDL) Levels From Five Years Before to Two Years After Intervention (Extended Time Frame)
One component of cholesterol, used if data is on health record. An LDL level of 100 milligrams per deciliter (mg/dl) or lower is the desirable outcome.
Time frame: 7 years
Secondary
Low-density Lipoprotein (LDL) Levels From One Year Before to One Year After Intervention
One component of cholesterol, used if data is on health record. An LDL level of 100 milligrams per deciliter (mg/dl) or lower is the desirable outcome.
Time frame: 2 years
Secondary
Medical Cost in US Dollars From Five Years Before to Two Years After Intervention (Extended Time Frame)
Total annual amount of medical and pharmacy costs (sum) as reported by Geisinger Health Plan. Lower costs is the desirable outcome.
Time frame: 7 years
Secondary
Number of Prescriptions From Five Years Before to Two Years After Intervention (Extended Time Frame)
Total number of prescriptions (standard unit is prescription per number of days supplied) as reported by Geisinger Health Plan. Fewer prescriptions is the desirable outcome.
Time frame: 7 years
Secondary
Number of Unique Prescribed Medication From Five Years Before to Two Years After Intervention (Extended Time Frame)
Total number of unique prescribed medication in the past year as reported by Geisinger Health Plan. Less unique prescribed medication is the desirable outcome.
Time frame: 7 years
Secondary
Number of Visits From Five Years Before to Two Years After Intervention (Extended Time Frame)
Total number of primary care physician and specialist visits (sum) as reported by Geisinger Health Plan. Fewer visits is the desirable outcome.
Time frame: 7 years
Secondary
Systolic Blood Pressure From Five Years Before to Two Years After Intervention (Extended Time Frame)
Taken from annual checkup with primary care provider. Systolic blood pressure that is 120 millimeters of mercury (mmHg) or less is the desirable outcome.
Time frame: 7 years
Secondary
Triglyceride Levels From Five Years Before to Two Years After Intervention (Extended Time Frame)
One component of cholesterol, used if data is on health record. A triglyceride level of 150 milligrams per deciliter (mg/dl) or lower is the desirable outcome.
Time frame: 7 years
Secondary
Triglyceride Levels From One Year Before to One Year After Intervention
One component of cholesterol, used if data is on health record. A triglyceride level of 150 milligrams per deciliter (mg/dl) or lower is the desirable outcome.
Time frame: 2 years
Secondary
Values From One Year Before to One Year After Intervention of Depressed Mood and Anhedonia as Assessed by the Patient Health Questionnaire-2 (PHQ-2)
Although originally listed as secondary, this outcome measure was intended to be exploratory. Due to the largely null pattern of results on the primary outcomes, it was decided to forgo additional analysis at this time.
Time frame: 2 years