Table 2. Coprimary Outcome and Secondary Outcome Results by Intervention Group.

Measure	Adjusted mean change (95% CI)a		Difference in adjusted mean changes (95% CI)a	P value
	Attention control	I-STAND intervention
Primary outcomes
Sitting time (n = 246)
3 mo	−6.94 (−17.36 to 3.49)	−38.38 (−51.80 to −24.96)	−31.44 (−48.69 to −14.19)	<.001
6 mob	−8.51 (−23.97 to 6.95)	−40.36 (−54.86 to −25.85)	−31.85 (−52.91 to −10.79)	.003
SBP at 6 mo (n = 254) b	−3.19 (−5.44 to −0.94)	−6.67 (−8.82 to −4.52)	−3.48 (−6.68 to −0.28)	.03
DBP 6 mo (n = 254)b	−1.58 (−2.93 to −0.23)	−1.32 (−2.66 to 0.02)	0.27 (−1.63 to 2.16)	.78
Secondary outcomes
Weight at 6 mo (n = 210)	−3.45 (−4.95 to −1.94)	−3.56 (−5.50 to −1.63)	−0.12 (−2.61 to 2.38)	.93
BMI at 6 mo (n = 210)	−0.54 (−0.81 to −0.26)	−0.51 (−0.85 to −0.17)	0.02 (−0.42 to 0.47)	.92
Waist circumference at 6 mo (n = 248)	−0.64 (−1.09 to −0.19)	−1.00 (−1.55 to −0.45)	−0.36 (−1.09 to 0.36)	.33

Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); DBP, diastolic blood pressure; SBP, systolic blood pressure.

^a For adjusted mean change and difference, we fit a linear regression model with generalized estimating equations on the outcome change from baseline, including the time points 3 and 6 months in the same model with indicators for 6-month time point, I-STAND intervention, and interactions among these indicators, adjusting for baseline outcome, post–COVID-19 randomization indicator, baseline outcome and post–COVID-19 interaction, county, age, gender, race, BMI, arthritis, physical function, diabetes, hypertension, retirement status, and number of hypertensive medication classes. To obtain the adjustment mean change, we assumed the mean baseline covariate response for all randomized participants. For SBP and DBP, we give only 6-month outcomes because 3-month outcome data were collected only on participants enrolled during the COVID-19 pandemic.

^b Six months is the primary time point of the trial.