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Midlife women are at an elevated risk for cardiovascular disease (CVD) and associated mortality. Those who have additional risk conditions such as obesity or hypertension report specific barriers to engaging in cardioprotective behaviors such as physical activity (PA). Considerable effort has been devoted to understanding PA determinants and designing interventions for midlife women, although with suboptimal success, as increasing PA could meaningfully attenuate CVD risk. An updated approach to understanding PA among midlife women could improve upon existing resources by focusing on novel psychosocial influences on PA in this population (ie, body satisfaction, social interactions, social comparisons, mood state) and within-person relations between these influences and PA in the natural environment.
The overarching goal of Project WHADE (Women’s Health And Daily Experiences) is to use an ecological momentary assessment (EMA) approach to capture ecologically valid relations between midlife women’s psychosocial experiences and PA as they engage in their normal daily activities. The primary aim of the study is to identify within-person psychosocial predictors of variability in PA (ie, experiences associated with higher vs lower PA for a given individual).
Midlife women (aged 40-60 years) with one or more additional risk markers for CVD (eg, hypertension) will be recruited from primary care clinics and the general community (target n=100). Eligible women will complete an initial survey and a face-to-face baseline session before engaging in a 10-day EMA protocol. Psychosocial experiences will be assessed using a brief self-report via a smartphone 5 times per day, and PA will be assessed throughout waking hours using a research-grade monitor. Participants will return for a brief exit interview at the end of 10 days. Multilevel models that address the nested structure of EMA data will be used to evaluate the study aims.
Recruitment and enrollment are ongoing, and a total of 75 women have completed the protocol to date. Data collection is expected to be completed in Fall 2020.
Project WHADE is designed to identify naturally occurring psychosocial experiences that predict short-term variability in midlife women’s PA. As such, the results of this study should advance the current understanding of PA among midlife women by providing further insight into within-person psychosocial influences on PA in this group. In the future, this information could help inform the design of interventions for this population.
DERR1-10.2196/19044
This paper describes the rationale and design of Project WHADE (Women’s Health And Daily Experiences), an intensive, observational study designed to improve upon the current understanding of midlife women’s physical activity (PA) and inform PA interventions designed for this population. Midlife women (age 40-60 years [
PA is a cardioprotective behavior known to attenuate CVD risk, as adequate levels of PA contribute to reducing CVD risk factors such as waist circumference and blood pressure [
Increasing PA thus remains to be an important avenue for reducing midlife women’s risk for CVD, and using new approaches to understanding facilitators of and barriers to PA could meaningfully improve intervention efforts for this group. Project WHADE addresses this need in 2 ways. First, by focusing on midlife women’s psychosocial experiences that are indicated by both theory and evidence to serve as facilitators and barriers to their PA but are understudied in this group. These include
This approach assumes that the observed relations at the between-person level (which describes differences between people) correspond to the within-person level (which describes changes in the same person over a given time frame). In many cases, this assumption is incorrect. For example, although
Accumulating evidence shows the importance of specific psychosocial facilitators of and barriers to PA for midlife women that differ from those of men [
In line with multiple theoretical models of health behavior and behavior change processes [
Across the lifespan, women are more likely than men to use PA to manage weight or appearance [
Thus, it appears that the relation between body satisfaction and PA is complex. Both high and low satisfaction could motivate PA, and the circumstances that determine the direction of the association are not yet clear, especially as they pertain to midlife women’s experiences in their natural environments. Furthermore, engaging in PA for appearance-related reasons is associated with worse physiological health [
For many individuals, interactions with other people occur on and off throughout the day; some interactions are more meaningful than others, in that they prompt consequential thoughts, emotions, or behaviors, whereas other interactions have little detectable effect on these outcomes [
In addition, the role of social interactions in PA appears to differ between women and men. Among adolescents and young adults, women cite the influence of social interactions on their PA decisions more often than men [
Moreover, although the social benefits of PA are also rated as more important among older versus younger women [
Social comparisons, or self-evaluations relative to others, represent an additional facet of social perception that may influence PA among midlife women. Comparisons with others are common in daily life and can be made across a range of domains (eg, appearance, wealth, work performance, health behaviors) and communication modes (eg, in person, via phone, via a social media platform) [
With respect to PA, social comparison may provide motivation via learning about discrepancies between one’s own PA engagement and that of others [
Experimental exposure to PA-based social comparison opportunities (eg, PA leaderboards, step competitions) shows positive group-level effects on subsequent PA and outperforms behavior change techniques such as enhancing social support when individuals are experimentally exposed to only 1 technique [
However, not all individuals respond positively to social comparison opportunities [
Taken together, existing evidence indicates that social comparisons may have a meaningful influence on PA and that this influence may be stronger for women than men. However, relations between comparisons and PA have rarely been examined among midlife women, especially at the within-person level. Greater attention to social comparison in this context could help to clarify the extent of its influence on PA in an at-risk group and provide needed insight into contextual factors that may explain previous equivocal findings (eg, identification and contrast processes).
Mood state describes an individual’s immediate emotional experience or a combination of emotional experiences (eg, happiness, sadness, anger). These may remain stable over periods of weeks or months or fluctuate in response to daily or momentary changes in context [
Several different mood states have been shown to predict PA over a range of time frames [
Research specific to midlife women confirms that PA engagement is inversely associated with negative affect in this population [
Recent evidence shows that when assessed repeatedly over hours and days, both PA and each of the psychosocial experiences described above (body satisfaction, social interactions, social comparisons, and mood state) can vary considerably within the same person [
In an EMA design, self-reports can be prompted by signals to handheld devices such as mobile phones. The timing of responses can be verified by this technology, and item responses can be examined for temporal associations with one another or with other ambulatory assessments (eg, behavior in the real world). Examining within-person associations between EMA survey responses (eg, capturing psychosocial experiences) and objectively assessed PA in the natural environment is an underused approach to understanding PA variability and its influences in real time [
The primary aim of this study is to examine within-person relations between midlife women’s psychosocial experiences (ie, body satisfaction, social comparison, social interactions, and mood state) and their PA to identify moment-level experiences associated with higher versus lower PA for this population. Secondary aims are to determine the timing and duration of these effects and to examine person-level moderators of within-person relations. Specific research questions to be addressed in this study include the following:
To what extent do body satisfaction, perceptions of social interactions, social comparisons, and mood state vary between- versus within-person among midlife women with elevated CVD risk?
To what extent does PA vary between- versus within-person among midlife women with elevated CVD risk?
Are moment-level differences in body satisfaction, perceptions of social interactions, social comparisons, and mood state related to differences in PA for these women (within-person)?
Do person-level characteristics such as age, BMI, or menopause status moderate within-person relations between psychosocial experiences and PA for these women?
The purpose of this paper is to present the protocol for an EMA study designed to capture within-person relations between psychosocial experiences (ie, body satisfaction, social interactions, social comparisons, mood state) and PA among midlife women with elevated cardiovascular risk.
Project WHADE is a study of relations between midlife women’s psychosocial experiences and PA in everyday life. Midlife women (aged 40-60 years) with one or more CVD risk markers complete a 10-day EMA procedure, whereby they self-report on their recent body satisfaction, social interactions, social comparisons, and mood at 5 semirandom times per day. For the same 10 days, they also wear a waistband accelerometer to capture their PA during waking hours. All study activities were approved by the Rowan University and Rowan School of Osteopathic Medicine institutional review boards (approval Pro2018002377).
Women are eligible if they are aged 40 to 60 years (inclusive) and have one or more additional cardiovascular risk factors. These include smoking (current or quit within the past 3 months) or diagnoses of prediabetes, type 2 diabetes, hypertension, prehypertension, hyperlipidemia, hypercholesterolemia, or metabolic syndrome. Additional inclusion criteria were English language proficiency, no medical contraindications to PA, not currently pregnant, not currently engaged in a formal weight loss program, no comorbid medical conditions or psychiatric symptoms that would impede participation (eg, injury, active psychosis), and the ability to complete momentary electronic surveys via a personal mobile device (eg, smartphone or tablet). Individuals are excluded from participation if they do not meet the above criteria or if they state an intention to move away from the geographic area during the study period. Eligibility was not limited by current level of PA engagement, as existing evidence and pilot work suggested that engagement would range from low to moderate for the target population [
The recruitment goal for this study is 100 participants and still ongoing. The sample size was calculated for cross-level multilevel models (described below) following estimates from simulations by Hox [
This study uses 2 primary recruitment strategies: web or print advertisements and direct referrals from providers in family medicine clinics. Web advertisements include a study-specific webpage, email announcements for employees and students at the supporting institution, social media posts (eg, Craigslist, Twitter, Facebook), and advertisements on local news websites. Print advertisements (ie, flyers, postcards) are posted in public locations such as libraries and community centers and appear in local newspapers. All advertisements provide phone and email contact information for the research team and offer interested individuals the option to complete an initial survey as their first step (see below).
Direct referrals take place on-site in family medicine clinics run by Rowan School of Osteopathic Medicine. Study collaborators identify patients with upcoming appointments who meet the eligibility criteria (based on chart review) and provide them with study information following their medical visit. Study staff are available on certain days of the week to provide additional information to interested individuals and to schedule telephone screenings.
Potential participants are asked to complete a 10-min telephone screening with trained research staff, who verify eligibility, explain study procedures, and answer questions. Those who remain interested in participating are scheduled for a face-to-face setup appointment (baseline) and are directed to complete an initial electronic survey before their appointment. Women who take the initial survey as their first expression of interest receive a follow-up call and/or email from study staff to complete or schedule the screening call, respectively.
Eligible women who engage in telephone screening and schedule an initial appointment are sent a Qualtrics survey link via email. This survey assesses demographics, contact information, recent psychosocial and physical experiences (eg, symptoms of depression and anxiety, health-related quality of life), global social perceptions (eg, social support, social comparison tendencies), and previous experience with PA promotion programs (self-guided and professionally supported). See
Baseline measures.
Construct | Description | Measure (reference) |
Demographics | Age, self-reported height and weight, income, education, marital status, ethnicity, race, medical conditions, menopause status | Developed for this study |
Social media behavior | Frequency of engagement with various social media platforms Example: How often to you use each of the following? (Facebook, Twitter, etc.) – Less than one day per week (1) to More than once per day (7) | Developed for this study |
Health-related quality of life | Physical and mental quality of life over the past four weeks | SF-36a Health Survey [ |
Activity barriers | Factors that are perceived to get in the way of PAb engagement | Barriers to Being Active Scale [ |
Exercise motivation | Expected outcomes of PA | Outcome Expectancies for Exercise Scale [ |
Lapses in exercise | Successful and unsuccessful attempts to increase exercise in the past year Example: In the past year, how many times have you started a formal exercise program, such as joining an ongoing group at a gym? (Numeric entry) | Developed for this study |
Anxiety | Symptoms of anxiety over the past month | Beck Anxiety Inventory [ |
Body image | Perceived influence of body image on quality of life | Body Image Quality of Life Inventory [ |
Depression | Symptoms of depression over the past four weeks | Center for Epidemiologic Studies Depression Scale [ |
Perceived stress | Perceived intensity of stress over the past month | Perceived Stress Scale [ |
Sleep quality | Subjective sleep quality and intensity of sleep disturbances over the past month | Pittsburgh Sleep Quality Index [ |
Problem orientation | Attitudes related to problem solving approach and abilities | Problem Orientation Questionnaire [ |
Social comparison |
Tendency to make social comparisons and value information from them | Iowa-Netherlands Social Comparison |
Social support | Perceived support from family and friends | Social Support Appraisals Scale [ |
aSF-36: 36-Item Short-Form Health Survey.
bPA: physical activity.
Women who complete the initial survey attend an on-site, 1-hour individual session at a research center with a trained staff member. During the visit, the staff member obtains written informed consent, measures the participant’s height and weight, and reviews study procedures. This includes wear and care of accelerometer and a detailed explanation of survey items. Instructions indicate that participants should complete EMA surveys within 1 hour of receiving them. This window for completing a survey was based on feasibility protocols from similar populations [
Participants are also given a folder with study materials to take home (eg, reminders from the baseline discussion, frequently asked questions about the accelerometer, an accelerometer wear log). The 10 days of EMA data collection in the participant’s natural environment are intended to begin the day after the participant’s baseline appointment. At the end of the baseline visit, participants are scheduled for a 15-min follow-up appointment to take place after the last day of the EMA data collection. See
Screening, enrollment, and data collection procedures. EMA: ecological momentary assessment.
The design of this study uses a signal-contingent approach, such that participants complete surveys in response to a signal (ie, text message). EMA surveys are scheduled and distributed via Qualtrics. Before study initiation, study staff generated survey schedules with semirandom timings anchored to 1 of 3 sets of specified times. These times were selected based on pilot work with the population of interest, which informed the expected frequency of events such as social comparisons, and were intended to maximize coverage of waking hours while minimizing reporting windows (and limiting retrospective recall) [
Survey distribution via text message with embedded web links is programmed immediately after a participant’s baseline appointment, and survey completion is monitored over the next 10 days. Research staff manually identify surveys outside of the 1-hour time window for reporting and surveys that repeat within the same 3-hour window (duplicates) for exclusion from statistical analyses.
After completing the 10-day accelerometer and survey protocol, participants return to the research center for their scheduled follow-up visit. Participants are asked to bring their accelerometer and a record of wear. A staff member conducts a brief exit interview to assess any difficulties, answer questions, and gather information about the participant’s preferences for future PA interventions. Participants who express interest in receiving mental and/or physical health resources are provided with materials sent via email. Those who indicate that they would like to view their PA engagement data are provided with a copy of their daily summaries. Summaries include daily totals for steps, sedentary time, and time spent in light, moderate, and vigorous activities.
Participants receive up to US $55 as compensation. They receive US $15 for attending the baseline appointment and US $30 when they return for follow-up. Those who return their accelerometers and complete more than 80% of EMA surveys receive an additional US $10 bonus at follow-up.
EMA items were initially based on those used in previous intensive longitudinal assessment studies and were pretested for revision with the target population in 2 ways. Initial items were generated using previous work as a guide and were distributed in a 7-day pilot EMA study with women who met the criteria for this study (June 2017-May 2018; n=13). These items were revised based on participant feedback, and modified items were discussed in individual face-to-face interviews with a different group of women who met the criteria for this study (October 2018-December 2018; n=10). Interview feedback informed further item refinement, and the items used in the EMA surveys are presented in
Sleep quality (first survey of the day only):
How would you describe your sleep last night?
Excellent
Good
Average
Poor
Terrible
Mood state:
How much have you experienced the following emotions: angry or frustrated, sad, happy or excited, content, anxious or stressed?
Not at all
Somewhat
Very much
Pain:
Have you had any physical pain in the last three hours?
Yes
No
If yes, which areas of your body? List all that apply.
If you have had pain, please rate the overall severity of your pain:
Mild
Moderate
Severe
Very severe
Positive social interactions:
Did you have positive or pleasant social experiences with any of the following today?
Friends
Coworkers
Acquaintances
Family
Strangers
Other
Total number of times you had positive or pleasant social experiences in the last three hours
Overall, how positive or pleasant were your social experiences in the last three hours?
Not at all
Moderately
Very
Negative social interactions:
Did you have negative or unpleasant social experiences with any of the following today?
Friends
Coworkers
Acquaintances
Family
Strangers
Other
Total number of times you had negative or unpleasant social experiences in the last three hours
Overall, how negative or unpleasant were your social experiences in the last three hours?
Not at all
Moderately
Very
Social comparisons:
In the last three hours, did you think about or evaluate yourself or your behavior in comparison to someone else (or someone else in comparison to yourself)?
Yes
No
How many times did you compare yourself to someone else in the last three hours?
Did you communicate with the person you compared to?
Yes. I talked to them in person, or on the telephone, or online (eg, Facebook message)
No. I saw, heard about, read about, or thought about them but did not communicate
Both
What aspects of yourself did you compare? Select all that apply.
Appearances
Health habits
Status
Emotions
Personality
Abilities
Other
Below are some interpretations of the comparisons you may have made. Please indicate how many of each type you made since the last time you responded. Comparisons to people who
Seem to be doing better than I am
Seem to be doing about the same as I am
Seem to be doing worse than I am
Most recent comparison:
Now consider only your most recent comparison. Did you communicate with the person you compared to?
Yes. I talked to them in person, or on the telephone, or online (eg, Facebook message)
No. I saw, heard about, read about, or thought about them but did not communicate
Both
What aspects of yourself did you compare? Select all that apply.
Appearances
Health habits
Status
Emotions
Personality
Abilities
Other
As you compared yourself, how much did you focus on each of the following: how similar I am to the person I compared to; how different I am to the person I compared to?
Not at all
Somewhat
Very much
After the comparison, how much did you feel each of the following: inspired, encouraged, or hopeful about my own situation; anxious, frustrated, or discouraged about my own situation?
Not at all
Somewhat
Very much
Motivation for physical activity (PA):
How motivated are you to be physically active in the next few hours?
Not at all
A little bit
Somewhat
Very
PA intentions:
Do you have plans to do cardiovascular exercise in the next few hours (such as going for a brisk walk or doing a strength DVD routine)?
No, no plans to exercise
Yes
If yes, how many planned minutes?
If yes, what kind of exercise?
Overall rating of the day (last survey of the day only):
Was today a typical day for you, with respect to physical activity or exercise?
Not at all. A lot less active than usual
Mostly. A little less active than usual
It was a typical day
Mostly. A little more active than usual
Not at all. A lot more active than usual
Was today a typical day for you, with respect to eating?
Not at all. A lot worse than usual
Mostly. A little worse than usual
It was a typical day
Mostly. A little better than usual
Not at all. A lot better than usual
Number of meals eaten today
Number of snacks eaten today
Current body satisfaction is assessed with 1 item (“How would you describe your body satisfaction right now?”). Responses are rated on a 4-point scale ranging from 1 (
Perceptions of social interactions since waking up (first survey of the day) or in the last 3 hours (all subsequent surveys of the day) are assessed with 6 items; 3 items focus on
Occurrence, type, and response to social comparison are assessed with 10 items. Participants are asked to report how many times they made social comparisons since they woke up (first survey of the day) or in the last 3 hours (all subsequent surveys of the day). Instructions specify that comparison includes any instance of evaluating an aspect of the self or one’s own behavior relative to that of others and that some comparisons might prompt emotional responses, whereas others might not. Both types should be counted in participants’ responses. Those who report one or more comparisons are asked what aspect or aspects of the self they compared (eg, appearance, health habits, abilities, etc) and the direction or directions of their comparisons (if they perceived the target to be upward, lateral [same as the self], or downward). Participants are also asked to provide these details about their most recent comparison before completing the survey, with additional items related to identification or contrast processes and affective response to the comparison (
Recent mood state is assessed with 5 items, referring to how much participants have experienced each emotion since they woke up (first survey of the day) or in the last three hours (all subsequent surveys of the day). Participants are asked to report on a three-point scale ranging from 1 (
These experiences are assessed using 4 items. First, participants are asked to report how motivated they are to be physically active within the next few hours (surveys 1-4 of the day) or on the following day (survey 5 of the day). Second, participants are asked whether they have intentions of doing cardiovascular exercise in the relevant time frame; if they answer “yes,” they are asked to record the number of minutes they plan to exercise and the type of exercise they plan to do (eg, walking, taking an exercise class) [
EMA surveys also query for additional experiences that may affect engagement in PA and end-of-day reports on PA and other health behaviors. These include sleep quality (first survey of the day), pain (occurrence, location or locations, and intensity; all surveys), perception of whether the day was typical with respect to PA and eating behavior (last survey of the day), and the number of meals and snacks consumed that day (last survey of the day) [
PA is assessed using the ActiGraph GT3X triaxial accelerometer (ActiGraph Corporation). Participants are instructed to wear the device aligned with their dominant hip during waking hours for 10 days following their baseline visit. They are asked to keep the device near their beds to limit forgetting to put it on upon waking, and to remove it for activities such as showering and swimming. Participants are also asked to complete a paper log for any time they remove the device for longer than 15 min during their waking hours, which is provided in the folder of study materials to bring home with them. PA parameters, including minutes of sedentary, light, moderate, and vigorous activity, are calculated using the ActiPro package for R. Moderate and vigorous minutes will be combined to estimate moderate-to-vigorous intensity physical activity. Time frames of interest include the concurrent reporting window (ie, 3 hours before each survey) and 30, 60, and 120 min after each survey to clarify the timing and duration of any observed effects [
Multilevel models will be used to address the nested structure of self-report and accelerometer data: momentary assessments (level 1) within days (level 2) within individuals (level 3). Missing data patterns will be evaluated, and all models will employ maximum likelihood estimation techniques, which include all available cases and are robust to missing data (such as missed surveys or missed items within surveys). Initial empty models will evaluate the proportion of variance accounted for at each level for each PA parameter using the intraclass correlation coefficient. Within-person relations between psychosocial determinants and PA will be tested (in separate models for each PA parameter) by controlling for person-level covariates and the stable, person-level association between the predictor of interest and PA. These models allow for the identification of moment-level differences from an individual’s average that are associated with higher- or lower-than-average PA. Age, BMI, menopausal status, and the number of CVD risk factors will be considered as covariates and may be examined as person-level moderators of within-person relations.
To date, 172 women have expressed interest in participating via email, phone, family medicine clinics, or the initial survey. Of these women, 101 were contacted for screening and scheduled a baseline appointment; 76 women attended the appointment, and 75 of then completed the full EMA protocol and returned for their follow-up appointment (99% retention). Most of the enrolled participants identified as white (56/75, 75%) and married (44/75, 59%); 23% (17/75) reported household incomes of less than US $50,000, and 23/75 (31%) did not finish a bachelor’s degree program or received an associate’s or technical degree. The largest subsets of participants qualify as obese (52/75, 69%), postmenopausal (29/75, 39%), and report a previous diagnosis of high cholesterol (39/75, 52%). Recruitment and enrollment will continue until the target sample size of 100 is reached (expected in Fall 2020).
Project WHADE is designed to assess 4 psychosocial experiences that are hypothesized to predict midlife women’s PA: body satisfaction, social interactions, social comparison, and mood state. This paper describes our approach to understanding within-person relations between these experiences and PA and highlights existing challenges to be considered in future work.
Given that EMA for capturing psychosocial influences on PA remains to be somewhat novel compared with other methods (eg, retrospective self-report, group-based experimental designs), there is limited evidence to inform key methodological decisions such as item wording for the constructs of interest, participant instructions, or optimal survey frequency and timing. As noted, we based the wording of our EMA items on those from existing, relevant studies and subjected them to 2 rounds of pilot testing with the population of interest. This also allowed us to gather feedback and estimates of survey and accelerometer compliance with the timing selected (ie, surveys 5 times per day and accelerometer wear for 10 days), which was intended to cover a representative subset of participants’ typical experiences while maximizing power and minimizing recording burden [
An advantage of EMA is its ability to assess experiences as they occur, using item wording that focuses on the present moment. In this study, we are intentionally using a different frame of reference (ie, “since you woke up/in the past three hours,” to capture time since the previous prompt) to assess social interactions, social comparisons, and mood state. This decision was based on the low likelihood of capturing social interactions and social comparisons in the moments that they occurred, as participants were not expected to interrupt social activities to complete the surveys. This approach also allows survey responses to capture events in the very recent past, rather than missing them if they are not currently happening. Similarly, we expected mood state to fluctuate throughout the day, and for mood states that predominated over 3-hour spans to be more predictive of PA than immediate emotions (which might be fleeting). For this reason, mood state was assessed as a summary of the past three hours, rather than as a reflection of mood state at the immediate moment of survey completion. Although decisions about the time frames for these reports were based on existing research and our specific research questions, it is important to acknowledge the associated limitations. Primarily, recall bias and forgetting are inherent in any retrospective report, and it will be possible that reports be skewed toward salient experiences or underestimate their true frequency in the natural environment [
An early consideration involved the method of distribution of EMA surveys to participants’ personal smartphones. Although professional services exist to manage survey distribution (and were considered for Project WHADE), payment regulations presented barriers to hiring outside assistance. Consequently, as in our pilot work, survey scheduling and distribution were managed by study staff, via Qualtrics. A strength of this method is that it offers researchers a great deal of control over and insight into the distribution process. However, this method is time-consuming for study staff and may be prone to error, and it requires additional time for rechecking to limit mistakes. The effectiveness of this method also depends on the cell phone carrier and network availability. For example, carriers periodically experience temporary outages during which text messages are not received. As individuals with certain coverage are not able to receive text messages from Qualtrics, a subset of participants are set up to receive EMA surveys via email and are asked to ensure that their smartphone email notifications mirror those of their text messages. To address this difference between participants, the method of survey delivery will be examined as a moderator of survey completion and responses and will be included as a covariate if it shows significant associations with either of these variables.
In addition, it is common for each survey to appear in a unique text message (rather than as a threaded conversation), and a small subset of participants has encountered confusion and completed the wrong survey when prompted. To ensure that the final dataset is accurate, survey numbers are coded manually by study staff based on their completion time stamps, and duplicates are deleted.
Despite these challenges, this study should provide useful insights into midlife women’s PA. Project WHADE is one of a limited number of studies that use EMA to identify within-person variability in and predictors of PA [
An additional advantage of EMA (and similar designs) is that it can be useful for identifying both group- and individual-level patterns. For example, it is possible that some midlife women are more likely to engage in PA after making an upward comparison, whereas others are more likely to engage in a downward comparison. As such, if a social comparison was included as a behavior change technique to be harnessed in future interventions for this population, it is possible that providing only 1 type of comparison opportunity (eg, exposing all participants to upward targets) would work well for some participants and not others. The use of EMA to identify these differences, which represent individual differences in within-person relations, could inform the tailoring of the content provided by future interventions to particular subgroups and individuals [
Together, these features of Project WHADE suggest that it is poised to address gaps in the current understanding of within-person processes associated with PA variability. We hope that a greater understanding of the within-person predictors of change in PA will provide information useful to the design of interventions, including novel just-in-time approaches that can respond to participants in real time [
Peer review report.
cardiovascular disease
ecological momentary assessment
physical activity
Women’s Health And Daily Experiences
This work was supported by the National Institutes of Health under the grant NHLBI K23136657 (principal investigator DA) and internal funding awarded to the first author.
None declared.