Targets

What is a target?

Targets are a form of goal for participants that can be automatically generated at different times during the study. The targets can be evaluated against in feedback or simply used to encourage the participant.

A target is tied to a single field of a single source. For example, it might be generated for "Nokia Blood Pressure Cuff", specifically for the "bloodpressure_systolic" field. If we need to evaluate multiple fields, we would generate multiple targets.

Targets have a specific start and end date, and a start value and end value. In many cases the start and end value will match; in other cases a participant might have a weight target which decreases linearly from the beginning to the end of a study.

How are targets used?

In device encounters, device upload data can be evaluated against a target, as seen below.

Targets can also be displayed on a participant's dashboard, either in a dedicated target card (such as in the /wiki/spaces/old/pages/21622391 study) or as an additional line in the device graph card (such as in the /wiki/spaces/old/pages/21622375).

How can targets be viewed by study staff?

• At Manage Participants → a participant → Targets, the target is shown with an entry for each day.
• On the Targets report, each target is shown once only, with the start date, end date, start value, and end value.
• The Target Compliance report shows all device data which was subject to a target. This report includes a column "extrapolated_target" (based on the start/end date/value, extrapolating to what the target would be at the time the datapoint was recorded.

How are targets generated?

• Most studies will need to have a target generator (on in tech speak, a targetbot) developed with the exact logic that should be used. Aside from any new code to be written, the admin user interface to set it up in each arm is currently limited to developers-only.
• Targets are usually generated relative to some sort of baseline value provided - this could be an in-person weigh in, device upload, or the like.
• Some target generators also look at a "dependent source/field" which provides an additional input (e.g. a survey response) that's used by the target generator.
• Targets are generated at study start, and can be updated with the "Reset targets" feedback consequence. This might be attached to a survey encounter, or to a regularly scheduled roundup.

How should targets be specified to simplify development?

Spec should include:

• From what data source are they generated?
• Are the stepped, linear, or constant?
• Will they ever be reevaluated? If so, when specifically? What are the rules for reevaluation?
• If there are manual steps (e.g. a participant chooses a new target) what happens if that manual step is skipped?

Baseline calculation spec should include:

• How many days is the baseline/run in period?
• Will the baseline/run in period need to be flexible or is it always a predefined number of days?
• Typically we consider the first day to be day # 0, is this ok? (e.g. the 7th and last day of week 1 would be day # 6 since the first day is day # 0)
• Are there any baseline calculation thresholds that should be considered? (e.g. ignore days where step count is under 1000 steps)
• Should any values be rounded?  If so, what is the nearest decimal/numeric place they should be rounded to?  Should the value be rounded to nearest value, always rounded up, or always rounded down? When exactly should the rounding take place?  
• Taking thresholds into consideration, what is the minimum amount of days (with valid data) necessary in order to calculate a realistic baseline? If this minimum amount of days is not reached by the end of the run in period what is the exact process to be followed?

Also, keep basic calculations in mind based on the length of the study. If we are breaking it down by weeks, 52 weeks multiplied by 7 days only equals 364 days. Which week should we squeeze in that extra day?

What studies have used targets in the past? How have they used them?

• /wiki/spaces/old/pages/21622374
  • Simple targets for systolic = 140, diastolic = 90
• /wiki/spaces/old/pages/21622375
  • Phase 1 (first 6 months)
    • Stepped target, losing 12 pounds over 24 weeks. Every 4 weeks their targets are reset - keeping the original 12 pound final target, but if they're above the trajectory, resets the targets to give them a new chance
  • Phase 2 (months 6-18)
    • Gives them a monthly option for whether they want to lose 0 or 1/2 pound per week for the next 4 weeks. This uses the goal setting survey developed as part of the /wiki/spaces/technical/pages/21594498 feature to ask them their goal.
• /wiki/spaces/old/pages/21622397
• /wiki/spaces/old/pages/21622357
• /wiki/spaces/old/pages/21622391
• charity
• STEPP
  • Start with baseline (average of first 14 days).  Week 1 (DAYS 0-8) target is 10% of baseline, week 2 (DAYS 9-15) target is 25% of baseline, week 3 (DAYS 16-22) target is 40% of baseline, week 4 (DAYS 23-29) target is 55% of baseline
• Diabetes Gamification
  • Step Count Target
    • This study begins with a 14 day run-in period. Using run-in days 8-14 (actually, 7-13 because it starts on day 0) we calculate a step count baseline average ignoring any days under 1000 steps. We must have at least 4 days of valid data to calculate the baseline. If a baseline is able to be calculated, we will display that in Manage Participants. Research coordinators will let the participant choose a step goal 33%, 40%, 50%, or a custom amount higher than the calculated baseline average. We will generate targets starting from the baseline entered in the survey, increasing by 25% of difference between goal and baseline each week during 4 week ramp up period. Maintain goal from week 4 through end of study (week 52)
  • Weight Goal Target

    • Participants will select a weight loss goal that is 6%, 7%, or 8% of their baseline rounded up to the next pound during an in-person visit. The weight loss goal will be set for the end of the first 6 months of the study. First week of study no change in weight. Steady decline from end of first week until 6-month mark.  After 6 months: If the participant has met their goal they will be expected to maintain that weight for the remaining 6 months. If the participant has not met their goal they will the option of striving to achieve either the full amount remaining or half of the amount remaining by the end of study (12 months). The slope of the weight loss trajectory should be reset every 4 weeks to give those falling behind a chance to catch up and those farther ahead the ability to slow down.