Table 2 Outcomes

Diet Quality

Dietary recalls of a non-consecutive weekday and weekend day will be performed via telephone using a multipass method and the Nutrition Data Systems for Research (NDSR) software [48]. The 2-days are averaged at each time point and Diet Quality calculated using the Healthy Eating Index (HEI)-2015, a tool used successfully in a broad range of populations (e.g., minority, older, cancer survivors), [49] will serve as a primary outcome for Project 3 as well as secondary outcomes for Projects 1 & 2, along with other data outcomes, e.g., energy intake and nutrient density.

Objectively-Measured Aerobic Physical Activity

Actigraph accelerometers (Fort Walton, FL) objectively capture physical activity over 7 days and are downloaded and processed using manufacturer procedures and software, and methods similar to those we have reported previously [11]. Moderate-to-vigorous activity assessed using these methods will serve as a primary outcome for Projects 2 and 3, and a secondary outcome for Project 1.

Weight

Measured in light clothing without shoes. The scale dial is captured on Zoom®, first as a “zeroed” value (prior to weighing) and then as the participant weighs. The assessor verifies the weight with both the participant and partner; the process is repeated and the average taken as a primary outcome for Projects 1 and 3 (secondary for Project 2).

Other Anthropometric Measures

- Height (self-reported)

- Waist circumference: Participant bares midriff to camera and places one end of the ribbon on umbilicus. Partner encircles the waist with the ribbon. The assessor then assures the ribbon is parallel to the floor and flat against the skin as participant rotates in front of camera. Upon exhale, the partner uses a felt-tip marker to mark the ribbon at the point of overlap [50, 51]. The process is repeated with the second ribbon; both ribbons are returned to the study office for measurement and averaging

Physical Performance Testing

The Senior Fitness Battery objectively assesses physical performance in several domains, is sensitive to change, devoid of ceiling effects, and has normative scores [52]. Typically done in-person, tests were adapted to virtual use, refined, and then evaluated for validity and reliability [53]; arm curls and grip strength, were not included given requirements for costly equipment and/or excessive postage.

- 30-s chair stand (lower body strength): A standard 18″ unpadded chair is used for this test, though if the participant does not have one, this is recorded and the identical chair is used for follow-up assessments. The participant sits in view of the camera and is instructed to cross arms with hands on shoulders. Upon the assessor’s signal to start, the participant stands up and sits down as many times as possible during a 30-s timed period.

- 8′ Get Up & Go test (agility, dynamic balance) Participant starts seated with crossed arms and hands on shoulders while the partner places a sticker and the end of the 8’cord (from mailed supplies) beneath the toe, drawing-out the cord to its full extension in front of the chair. The endpoint is marked by a soccer cone and the cord removed. After positioning the camera to capture the full course and with a focus on the chair (starting and ending points for this test), the participant is given the signal to start. The participant stands up, walks as fast as possible (without running) around the cone, returns to the chair, and sits down. The test is timed using the video – starting from the sign of movement until seated again.

- 8′ Walk (gait speed) The chair is removed and the participant starts standing with their toe on the sticker (see test above). Upon the signal to start, they walk as fast as possible through the 8′ point marked by 2 soccer cones (another cone is used to increase visualization) and the camera is focused on the finish-line. This test also is timed using the video – starting from the sign of movement until the finish line is crossed.

- Sit-and-reach (flexibility) Seated on the edge of the chair, the participant extends one leg so heel remains on floor, the knee is fully extended and the toe pointed to the ceiling. With the camera capturing the side view of the participant, they are instructed to overlap their hands and extend them towards the toe. The partner measures the distance from the middle finger to the big toe with a vinyl tape measure. Positive for over-reach, negative for under-reaching, zero for touching.

- Back scratch (flexibility) While standing with their back toward the camera, the participant reaches arm out and over same shoulder, reaches other arm directly back and attempts to clasp other hand. The partner measures the distance between closest fingers (scoring identical to the test above).

- 2-min step test (endurance) The partner is instructed to palpate the participant to locate the iliac crest and then uses the vinyl tape measure to record the distance to the top of the patella which is called-out to the assessor. The assessor calculates the midpoint which is denoted by a sticker. The partner is then asked to measure the distance from the sticker to the floor and call-out the value to the assessor. The assessor records this value for future testing and then instructs the partner to measure this distance against a wall and to mark it with another sticker. Upon the command to start, the participant “marches in place” for 2 min making sure to bring their knees up to point of the sticker. The participant is instructed not to talk, and to take breaks and steady themselves against the wall should they need to while timer continues (the partner also is instructed to “spot” the participant as needed). The number of steps reaching the mark are counted.

Balance Testing

Side-by-side, semi-tandem and tandem stance balance testing as per the Centers for Disease Control protocol is captured on Zoom® [54]. To reduce ceiling effects, the latter test is extended for up to 2 min (or until the stance is broken). This test is also performed near a wall should the participant need to steady themselves.

Blood Pressure

Participant is instructed to sit quietly in front of the camera for 5 min (during which time the assessor turns-off the Zoom® video). Once resumed, the partner is instructed to place the cuff of the automated sphygmomanometer on the participant and to press start (making sure the camera is focused on the display). The assessor reads the values and verifies them with the partner. Blood pressure is standardly assessed in the upper right arm, unless there are contraindications, such as surgery or radiation therapy on the right side; left side assessments are noted and repeated for follow-up assessments.

Muscle Mass

As in the Osteoporotic Fractures in Men (MrOS) Study, the deuterium creatine (D₃Cr) dilution method is used that capitalizes on a stable, non-radioactive isotope, to assess muscle mass remotely [55,56,57]. Participants are provided with a 30 mg capsule of D3Cr and instructed to take the capsule 3 days prior to their assessment date. The night prior to assessment, they begin fasting and continue fasting until they produce the second urinary void of the day. During this void, a test strip is used. The strip is frozen (0 C^o or below) until analyzed, using methods originally reported by Clark et al. and adapted by Evans et al. [55,56,57].

Circulating Biomarkers^a

Assessor guides the participant in obtaining 5 blood spots on a designated card, which is then dried thoroughly, inserted into a foil pouch with desiccant and frozen (0 C^o or below) until analyzed. DBS eluents are batch-tested against known standards for Thyroid Stimulating Hormone (TSH), insulin, glucose, leptin, adiponectin, high density lipoprotein and total cholesterol, triglycerides, interleukin-6, c-reactive protein and tumor necrosis factor alpha at the University of Washington as described previously [58]. Values are expressed in plasma equivalent terms.

Patient Reported Outcomes^a

Physical Activity: As accelerometry provides only activity counts, two common instruments are used to capture data on the various types of physical activities the participants engage in: 1) Godin Leisure-Time Exercise Questionnaire (GLTEQ) is administered given its ease of use and excellent reliability and validity in cancer survivors [59]. An updated version that includes frequency and average minutes of duration of exercise/week within intensity categories (strenuous, moderate [including strength training] and mild) was selected for the current study [60]; and 2) Global Physical Activity Questionnaire (GPAQ) is a 16-item instrument developed for the World Health Organization that assesses physical activity within the contexts of recreation, work and travel. It also measures sedentary behavior and has proven validity and reliability across a broad spectrum of populations [61].

Cancer-related Outcomes: The PROMIS Cancer-Related Item Bank is used to assess global physical, mental and social health, perceived stress, and QOL in specific domains, i.e., depression, anxiety, fatigue, sleep, and pain [62]. This tool was synthesized from previous QoL instruments (FACT, EORTC, etc.) and relies on item response theory and complex algorithms to pinpoint the most relevant items in each domain, while reducing the number of items assessed (patient burden). This measure will be completed over the phone or self-administered online, as in past studies [63].

Quality of Life: QOL will be measured with the PROMIS global health scale and the EuroQOL-5D-5L (EQ-5D-5L) The EQ-5D-5L assesses 5 dimensions (Mobility, Self-care, Pain/Discomfort, and Anxiety/Depression) [64] at 5 levels of severity: its scores of this instrument are used to calculate Quality Adjusted Life Years.

Health Care Utilization the validated instrument of Ritter et al. has test-retest reliability of 0.76–0.97 and will capture physician and emergency room visits, and hospitalizations [65], and will be amended to include out-of-pocket costs related to medical visits, and costs of prescribed and over the counter medications [66].

Comorbidity: The Older Americans Resources & Services (OARS) Comorbidity Index (43-items) used in multiple studies in older adults will assess the number of chronic medical conditions and symptoms and their functional impact (severity). In addition to serving as an outcome, comorbidity at baseline will be evaluated as a potential moderator. Since falls are a particular issue in this population, an item validated by Chen & Janke that assesses falls in the past year also will be included [67].