Appendix A: Intervention Development, including Power Calculations

Power Calculations

To calculate the sample size needed for this study, we used data from another group-based weight program conducted in our clinic to estimate the expected effect size (34). Early data from this project showed that a 6.8 lb (SD 1.8) change in weight among those who enrolled the program. We estimated that with a sample size of 80 (40 in each group), we would have 85% power to detect the minimal effect size of 0.34 in weight change between the two groups. The power calculation was based on one-way ANOVA test with α = 0.05., using weight loss as the outcome and intervention status as the predictor. We planned to recruit 100 people to our trial so that with drop-outs we will still have sufficient power to detect between-group differences.

Intervention Development

The intervention components for the IL intervention were chosen based on from a lifestyle intervention for pre- and postmenopausal women (13, 16-17) as well as portions of the Diabetes Prevention Program (DPP) (18). We also used information from focus groups with postmenopausal women on physical activity preferences(35). As a comparison intervention for the SG group, we used the Choose to Move program developed by the American Heart Association(20), which is also an evidence-based program(36). Appendix Table A list the sessions of the IL intervention with references for each, as well as the group physical activity performed at the session. Appendix Table A also lists the corresponding 12 topics of the Choose to Move Program.

Appendix Table A. Healthy Bodies, Healthy Hearts Interventionist-led Intervention Sessions and Activities and Self-Guided Sessions

Interventionist-Led Group Sessions / Self-Guided Sessions
Session / Lesson Topic / Physical Activity/Other Activity / Choose to Move(20)
1 / Getting Started / Stretching / Choosing to Move
2 / Pedometer Pointers (13, 18) / Walking / Creating a Plan of Action
3 / Time management (13, 18) / Walking / Strengthening Your Resolve
4 / Mindful eating (19, 37) / Meditation (hunger, taste, satiety, eating) / Accentuating the Positive
5 / Stress management (18) / Yoga / Avoiding Traps and Trip-Ups
6 / Barriers to exercise (13, 18) / Walking, yoga, or stretching / Reaching for More
7 / Social support and assertion (13) / Therabands/resistance training / De-Stressing the Stressed Out
8 / Mindful exercise/
awareness of body (19, 38) / Mindful movement and yoga / Finding Community Resources
9 / Prevent boredom (13, 18) / Circuit training / Lapsing and Snapping Back
10 / Lapses in physical activity (35) / Dance / Staying Motivated
11 / Staying Active/ Review/Community Resources (13, 18) / Participants’ choice (walking, yoga, stretching, resistance training or dance) / Planning for the Future
12 / Seeing Results/Wrap up (13, 18) / Dance / Keep Moving, Keep Choosing

Appendix B: Exploratory Psychosocial Measures

Exploratory Psychosocial Measures

Exercise Self-Efficacy was assessed using a previously validated and reliable instrument designed to assess confidence in exercising in five challenging situations (21-23).

Health-Related Quality of Life was assessed using the Short Form-12 Health Survey (SF-12) (20).

Sleep was measured using the Pittsburgh Sleep Quality Index (PSQI) (19). The sleep quality variable from the PSQI questionnaire is a global score ranging from 0 to 21 generated from a summation of the seven components. A higher score indicates worse sleep quality, with a score > 5 suggesting significant sleep disturbance.

Physical Activity Enjoyment was assessed by the Physical Activity Enjoyment Scale (PACES), a self-reported 18-item scale (17). Subjects rate their current feelings about physical activity on a 7-point Likert scale. Validation of the scale demonstrated a strong internal consistency (.93) and stable validity (17).

Depression was assessed using the Beck Depression Inventory (BDI). The BDI is a validated, reliable, 21-item survey intended to assess the burden of depressive symptoms (Cronbach’s alpha = 0.74) (18). Scores for the BDI range from 0 to 63. Scores in the range of 0–9 (i.e., the majority of our population) represent minimal depressive symptoms.

Baseline Psychosocial Measures

The baseline psychosocial characteristics of the HBHH participants are listed in Appendix Table B1. Most characteristics did not differ by randomized group, although women in the in-person group had a higher BMI (36.1 vs. 33.4; p=0.02) and a higher PA self-efficacy score (40.3 vs. 35.3), indicating greater confidence in ability to perform exercise, when compared to those in the at-home group.

Changes in Psychosocial Measures

There was a trend toward a greater reduction in BDI, indicating lower levels of depressive symptoms, in the interventionist-led group (-2.0 vs. 0.50; p=0.06) when compared with the self-guided group (Appendix Table B2). There were no significant differences between groups with regard to changes in PA self-efficacy, health-related quality of life (SF-12), sleep, or physical activity enjoyment (PACES) at 3 months. There were no significant differences in changes in psychosocial variables between IL and SG groups at 12 months.

Variable / Total (n=98)
mean(std) / n(%) / IL* (n=49)
mean(std) / n(%) / SG* (n=49)
mean(std) / n(%) / p-value
Self-efficacy / 37.8 (9.90) / 40.3 (9.77) / 35.3 (9.49) / 0.01**
SF-12 PCS / 48.0 (8.42) / 47.1 (9.10) / 48.8 (7.67) / 0.32
SF-12 MCS / 49.1 (10.45) / 49.6 (10.24) / 48.6 (10.73) / 0.63
PSQI Sleep Quality / 7.0 (4.19) / 7.0 (4.33) / 7.1 (4.09) / 0.89
PACES / 47.7 (5.48) / 48.2 (5.77) / 47.2 (5.19) / 0.36
BDI / 7.0(4.0,12.0) / 9.0(4.0,13.0) / 5.0 (4.0,9.0) / 0.10a

Appendix Table B1. Baseline Characteristics of HBHH Participants (n=98)

Appendix Table B2. Changes in exploratory psychosocial outcomes at 3 and 12 months (complete data only)

3-month / 12-month
Variable / Total (N=98) / In Person (n=49) / At Home (n=49) / p-value / Total (N=98) / In Person (n=49) / At Home (n=49) / p-value
Self Efficacy / -0.91 (8.51)
(n=68) / -1.24 (8.43)
(n=41) / -0.41 (8.78)
(n=27) / 0.69 / -0.95 (9.62)
(n=61) / -0.65 (9.46)
(n=37) / -1.42 (10.05)
(n=24) / 0.76
SF-12 PCS / 0.12 (7.49)
(n=68) / 0.89 (8.46)
(n=41) / -1.05 (5.67)
(n=27) / 0.26 / -0.21 (7.59)
(n=61) / -0.27 (7.84)
(n=37) / -0.13 (7.35)
(n=24) / 0.94
SF-12 MCS / -1.65 (9.75)
(n=68) / -1.74 (10.95)
(n=41) / -1.50 (7.77)
(n=27) / 0.91 / 1.11 (9.33)
(n=61) / 1.04 (10.12)
(n=37) / 1.21 (8.18)
(n=24) / 0.94
PSQI Sleep Quality / -0.16 (2.87)
(n=68) / -0.37 (3.19)
(n=41) / 0.15 (2.31)
(n=27) / 0.44 / 0.10 (3.06)
(n=61) / -0.08 (3.48)
(n=37) / 0.38 (2.33)
(n=24) / 0.54
PACES / 0.84 (5.24)
(n=68) / 1.02 (5.42)
(n=41) / 0.55 (5.03)
(n=27) / 0.72 / -0.70 (7.10)
(n=61) / 0.64 (5.81)
(n=37) / -2.79 (8.43)
(n=24) / 0.09
BDI a / (n=67)
Median =-1, (-5,-3) / (n=41)
Median=-2, (-5,2) / (n=26)
Median=0.5 (-2, 4) / 0.06 a / (n=67)
Median=-1, (-5,1) / (n=42)
Median=-1.5 (-4,1) / Median=-1, (-5,0)
(n=25) / 0.94 a