Introduction

BioStamp® nPoint™ collects high-resolution physiological data from sensors worn by subjects participating in clinical trials, or studies. This raw signal data produces recordings, which can be further processed into analytics for use as clinical endpoints:

Both raw signal data and analytics can be used as inputs into advanced algorithm development.

BioStamp® nPoint™ also collects contextual data, or annotations, that can be aligned to the physiological data stream:

Other metadata—about equipment usage, adherence to prescribed activities, messages exchanged between subjects and study administrators, and important system events—can provide additional insights into the progress of a study:

Developers can use the MC10 API to integrate BioStamp® nPoint™ data into their own systems, either periodically during the course of a study or as batch operations after a study is completed.

High-resolution sensor data (Recordings)

Sensors are configured at the start of a study to capture data from specific body locations, such as the bicep on the subject's dominant side, from every subject in the same way. This data may include:

  • Acceleration values from an accelerometer, expressed as g-forces

  • Rotation values from a gyroscope, expressed as degrees per second

  • Biopotential values from skin-contact electrodes, expressed as volts

BioStamp® nPoint™ supports four sensing modalities:

  • Accelerometer

  • Gyroscope + Accelerometer

  • Electrodes

  • Electrodes + Accelerometer

A sensor’s runtime depends on its configuration and is limited by either battery life or memory. The following table shows estimated runtimes under normal environmental conditions:

ACCEL
GYRO + ACCEL
ELECTRODES
ELECTRODES + ACCEL

Sample Rate

Runtime

Limit

15.625Hz

145 hrs.

Battery

31.25Hz

93 hrs.

Memory

62.5Hz

46 hrs.

Memory

125Hz

23 hrs.

Memory

250Hz

11 hrs.

Memory

Accel Ranges: +/- 2G, +/- 4G, +/- 8G, +/- 16G

Gyro Sample Rate

Accel Sample Rate

Runtime

Limit

15.625Hz

15.625Hz

14 hrs.

Battery

31.25Hz

31.25Hz

13 hrs.

Battery

62.5Hz

62.5Hz

13 hrs.

Battery

125Hz

125Hz

11 hrs.

Memory

250Hz

250Hz

5 hrs.

Memory

Gyro Ranges: +/- 250°/s, +/- 500°/s, +/- 1000°/s, +/- 2000°/s; Accel Ranges: +/- 2G, +/- 4G, +/- 8G, +/- 16G

Sample Rate

Runtime

Limit

125Hz

70 hrs.

Memory

250Hz

35 hrs.

Memory

500Hz

17 hrs.

Memory

1000Hz

8 hrs.

Memory

Elec Range: +/- 300 mVDC

Elec Sample Rate

Accel Sample Rate

Runtime

Limit

125Hz

125Hz

40 hrs.

Memory

250Hz

125Hz

25 hrs.

Memory

500Hz

125Hz

14 hrs.

Memory

1000Hz

125Hz

8 hrs.

Memory

Elec Range: +/- 300 mVDC; Accel Ranges: +/- 2G, +/- 4G, +/- 8G, +/- 16G

Physiological metrics (Analytics)

When a study uses analytics, the raw signal data is processed into 45 physiological metrics categorized by sleeping, resting and moving:

SLEEPING
RESTING
MOVING

Metric

Unit

Total Sleep Duration

Seconds

Sleeping Avg. Heart Rate

Beats Per Minute

Sleeping Min. Heart Rate

Beats Per Minute

Sleeping Max. Heart Rate

Beats Per Minute

Sleeping Avg. HRV (LF/HF)

N/A

Sleeping Min. HRV (LF/HF)

N/A

Sleeping Max. HRV (LF/HF)

N/A

Sleeping Avg. HRV (RMSSD)

Milliseconds

Sleeping Min. HRV (RMSSD)

Milliseconds

Sleeping Max. HRV (RMSSD)

Milliseconds

Sleeping Avg. Respiration Rate

Breaths Per Minute

Sleeping Min. Respiration Rate

Breaths Per Minute

Sleeping Max. Respiration Rate

Breaths Per Minute

Sleeping Posture Transition Count

N/A

Sleep Onset Time

N/A

Sleep Wake Time

N/A

Metric

Unit

Total Rest Duration

Seconds

Lying Duration

Seconds

Sitting Duration

Seconds

Standing Duration

Seconds

Upright Posture Duration

Seconds

Leaning Posture Duration

Seconds

Resting Avg. Heart Rate

Beats Per Minute

Resting Min. Heart Rate

Beats Per Minute

Resting Max. Heart Rate

Beats Per Minute

Resting Avg. HRV (LF/HF)

N/A

Resting Min. HRV (LF/HF)

N/A

Resting Max. HRV (LF/HF)

N/A

Resting Avg. HRV (RMSSD)

Milliseconds

Resting Min. HRV (RMSSD)

Milliseconds

Resting Max. HRV (RMSSD)

Milliseconds

Metric

Unit

Total Moving Duration

Seconds

Walking Duration

Seconds

Other Movement Duration

Seconds

Avg. Gait Cadence

Steps Per Minute

Step Count

N/A

Moving Avg. Heart Rate

Beats Per Minute

Moving Min. Heart Rate

Beats Per Minute

Moving Max. Heart Rate

Beats Per Minute

Moving Avg. HRV (LF/HF)

N/A

Moving Min. HRV (LF/HF)

N/A

Moving Max. HRV (LF/HF)

N/A

Moving Avg. HRV (RMSSD)

Milliseconds

Moving Min. HRV (RMSSD)

Milliseconds

Moving Max. HRV (RMSSD)

Milliseconds

Metrics are generated each day a subject participates in a remote program at home.

Continuous activity classification outputs are available at a minimum of 5-second resolution. Sleep, respiration, heart rate, and HRV are all available at a minimum of 1-minute resolution.

Annotations

Three types of annotations add context to a subject's physiological data:

  • Prescribed activities

  • Prescribed surveys

  • Manually-entered labels

Activities and surveys are administered through the BioStamp® nPoint™ Link app or BioStamp® nPoint™ Investigator app to ensure exact alignment with raw recording data:

Study administrators can enter labels via the BioStamp® nPoint™ Investigator Portal in order to indicate areas of interest:

Study and subject metadata

Several API endpoints include metadata to provide operational insights into the progress of a study, such as: