Table 1.

Personal, family, friend, school, and neighborhood predictors of adolescent physical activity

Personal	Measure description
PA self- efficacy	3-item PA self-efficacy scale45,46
PA barriers	4 items, barriers to PA: weather, time, school work, embarrassed about how I look when I’m active47,48
PA enjoyme nt	3-item PA enjoyment scale: I feel bored, I dislike it, it frustrates me49
PA self- managem ent	3-item PA self-management scale: set goals, backup plan, I can get back on track47
Sport participat ion	During the past 12 months, on how many sports teams did you play? (0 teams, 1 team, 2 teams, ≥3 teams)
Family
Home PA resources	Count of PA resources available to your child in your home, yard, or apartment complex (stationary aerobic equipment [bicycle, treadmill, etc.], bicycle, skateboard, scooter, rollerskates/blades, basketball hoop, weight-lifting equipment [free weights, Nautilus, Universal, etc.], interactive video games [Wii Sport/Fit, Dance Dance Revolution]).
Parent- reported weekly PA	Parent self-reported total weekly hours of PA22
Perceive d mom’s PA	My mother is physically active in her free time. (never, rarely, sometimes, on a regular basis)
Perceive d dad’s PA	My father is physically active in his free time. (never, rarely, sometimes, on a regular basis)
Parent active with child	In a typical week, how many hours do you spend being physically active with your child (e.g., throwing a ball around, taking a walk or bike ride together)? (none, <0.5 hours, 0.5–2 hours, 2.5–4 hours, 4.5–6 hours, ≥6 hours)
Parent helps child be active	In a typical week, how many hours do you spend helping your child to be physically active (e.g., driving them to the gym or sport practice, watching them play a sport)? (none, <0.5 hours, 0.5–2 hours, 2.5–4 hours, 4.5–6 hours, ≥6 hours)
Family support for PA	Composite of 2 items: (1) My family (including parents and siblings) and I do active things together (e.g., bike rides, walks); and (2) My family supports me in being physically active (e.g., enrolling me in sports, watching me perform, providing transportation to places to be active). (strongly disagree, somewhat disagree, somewhat agree, strongly agree)
Friends
Friend support for PA	Composite variable: 3 items asking about perceptions of friends’ participation in PA, sports, and support for PA50
Male friends’ MVPA	MVPA hours per week reported by male friends
Female friends’ MVPA	MVPA hours per week reported by female friends
Male friends play sports	Percentage of male friends reporting that they play team sports
Female friends play sports	Percentage of female friends reporting that they play team sports
School
Currently taking P.E.	Are you currently taking a physical education or gym class at school? (yes/no)
Total indoor PA facilities	Facilities school has access to for indoor physical education (Mark all that apply: gymnasium, pool, weight room, cardio center, wrestling room, dance studio, P.E. classrooms, P.E. multipurpose area, other indoor P.E. facility)
Total outdoor PA facilities	Facilities school has access to for outdoor physical education (Mark all that apply: track, volleyball court, basketball court, tennis court, baseball field, football field, black top, other outdoor P.E. facility.)
P.E. facilities well maintain ed	Are your school’s physical education facilities well maintained and usable? (not at all, somewhat, mostly, very well)
Activity fee	Must students pay an activity fee to participate in any sports, intramural activities, or physical activity clubs? (yes, no)
Late bus	Does school have “late bus” home for students staying after school for academic, club, or discipline reasons? (no, yes)
Sport bus	Does this school provide transportation home for students who participate in after-school sports, intramural activities, or physical activity clubs that is separate from the “late bus” in the previous question? (no, yes)
School promotin g PA	Are there activities currently underway at your school to promote increased physical activity among students?
School effort promotin g PA	In your opinion, to what extent has your school made a serious/real effort to promote increased physical activity among students? (not at all, to a little extent, to some extent, to a great extent, to a very great extent)
District effort promotin g PA	In your opinion, to what extent has your school district made a serious/real effort to promote increased physical activity among students? (not at all, to a little extent, to some extent, to a great extent, to a very great extent)
Student campaign involvem ent	In the past year, have students been involved in school assemblies, events, or campaigns promoting physical activity?
Groups use school PA facilities	Outside of school hours or when school is not in session, do outside groups conduct physical activity or sports programs on school grounds or in school facilities? (yes, no)
Teams use school PA facilities	Outside of school hours or when school is not in session, do students use any of this school’s physical activity or athletic facilities for community sponsored sports teams? (yes, no)
Open gym in school PA facilities	Outside of school hours or when school is not in session, do students use any of this school’s physical activity or athletic facilities for community-sponsored supervised “open-gym” or “free-play?” (yes, no)
Neighbo rhood
Neighbor hood safety	Composite of two items regarding safety in the neighborhood where participant lived for the majority of the past year. 0 indicates always safe, 1 indicates unsafe only at night, 2 indicates unsafe day and night51,52
Crime (density)	Total number of crimes in 2010 within crime grid zone or neighborhood
Green space (distance )	Straight-line distance in meters to nearest park/recreation space
Green space (%)	1600-meter straight-line buffer percent park/recreation space
Recreatio n center (distance )	Road network distance in meters to nearest recreation center
Recreatio n center (density)	1600-meter straight-line buffer count of recreation centers
Gym (distance )	Road network distance in meters to nearest gym/fitness center
Gym (density)	1600-meter road network buffer density of gyms/fitness centers (count per hectare, excluding water)
Trail (distance )	Straight-line distance in meters to nearest bike or walking trail
Transit stops (density)	1600-meter network buffer count of transit stops
Busy streets (density)	1600-meter road network buffer percent busy streets
Access points (density)	1600-meter straight line buffer count of access points
School (distance )	Road network distance in meters to school attended
Woman- headed househol ds (%)	Proportion of households headed by women within Census tract
High school graduates (%)	Proportion of residents with high school degree within Census tract
Median househol d income	Median household income in the past year (in 2009 inflation-adjusted dollars) within Census tract
Below poverty (%)	Proportion of households in census tract with incomes below 100% of the poverty threshold
Age <18 years (%)	Proportion of population aged ≤17 years within Census tract
Populatio n (density)	1600-meter straight-line buffer 2010 population count per hectare, excluding water