Working with PAL data files (V8)

.datx files

The datx file is the raw unprocessed data file from the activPAL. To generate the analysis outcomes, files need to be processed in PALanalysis (or by batch processing files in PALbatch).

PAL datx files can be opened in PALanalysis by:

• Clicking browse to open a dialog box to locate the file
• Dragging and dropping the datx file on to the window

(Windows version only) Double clicking on a datx file in Windows explorer will directly open the file in PALanalysis

.pml files

When opening datx files, PALanalysis will generate an accompanying .pml file. This stores user definitions, e.g. user defined Time in Bed. To retain any user defined changes, the pml file should be retained with the datx file.

Visualisations

Events spiral

This visualisation displays the classified events as a spiral heat map. By default each loop of the spiral displays a day of data – the outer loop is the start of the recording, and the data spirals inwards to the centre.

Visualisation options

Week per loop

In the top menu, the time period per loop can be changed to week per loop. This option is mostly used for looking at recordings which have multiple weeks of data.

Highlight upright events

This visualisation option (selected in the checkbox area on the bottom left) varies the thickness of the spiral segments by event type, providing a greater visual separation of standing and stepping events from non-upright events.

Show seated transport events

This visualisation option (selected in the checkbox area on the bottom left) displays the seated transport classification on the event spiral (highlighted in the pink colour). 

Show cycling events

This visualisation option (selected in the checkbox area on the bottom left) displays the cycling classification on the event spiral (highlighted in the purple colour).

Events linear

This visualisation displays by default a day per row heat map with daily summary totals. 

Visualisation options

Hour per row

In the top menu, the time period per row can be changed to hour per row. This provides a detailed view of each individual day. The day displayed can be changed in the top bar menu.

Epochs

This visualisation displays for each day an hour by hour epoch summary and daily summary. 

Sedentary bouts

This visualisation highlights the duration of sedentary bouts in the data on a colour scale from yellow through to dark orange. Time in bed periods and upright periods are shown for context.

Time in Bed

This visualisation shows the algorithm defined time in bed definitions, and allows for these to be adjusted.

Acceleration spiral

This visualisation displays the raw triaxial accelerometer data on the spiral, with a day of data on each loop.

Inclination and vector magnitude

This visualisation displays the changes in the inclination and dynamic accelerations in the recording. 

Stillness and rolling

This visualisation shows the stillness of the device and the rolling during sedentary periods as identified by its location on the thigh.

The vertical height of the blocks show the stillness of the device, and the shades of blue indicate the proportion of the non-upright bout in different rolling orientations.

Exports

The outcomes of the analysis can be exported in multiple ways. Full details on each export are described in the Exports section.

For each visualisation, clicking on “Export…” provides a subset of relevant exports to the current view. Clicking on “Generate Exports” will generate the selected exports in the containing folder of the datx file.

Clicking on “All exports…” launches the full exports page, which shows all available exports from the software. Multiple items can be selected at once. The exports are created in the containing folder of the datx file.

Export Log file

For convenience of tracking exports and the processing parameters a timestamped log file is created for each export:

/Documents/PAL/userlogs/PALanalysisExportLog_YYYYMMDD

Settings

The following settings can be adjusted for PALanalysis:

validation algorithm

Adjustable criteria for the validation algorithm

Wear time protocol:

• 24 hour wear – allows 4 hours of non-wear per day
• 14 hour waking wear day – allow 10 hours of non-wear per day
• 10 hour wear day – allow 14 hours of non-wear per day

classification algorithm

The classification algorithm can be selected and parameters adjusted.

VANE
The standard PAL analysis algorithm. Classifies the data into 3 event types – non-upright, upright and stepping.

Adjustable parameters:

• minimum non-upright period – for free living data in adult populations, the default value of 10 seconds is recommended
• minimum upright period – for free living data in adult populations, the default value of 10 seconds is recommended

CREA
Extends the standard PAL analysis algorithm to provide detection of non-wear and classification of non-upright time into lying (primary and secondary) and sitting. Seated transport and cycling classification are applied. Upright correction for intermediate sitting angles is also applied.

Adjustable parameters:

• minimum non-upright period – for free living data in adult populations, the default value of 10 seconds is recommended
• minimum upright period – for free living data in adult populations, the default value of 10 seconds is recommended

Wear correction

With ‘Auto-correct inverted wear’ selected, data files where the device was worn upside down will be automatically corrected.

Version History

8.11.8.74    (24th May 2022)

Added

• GHLA algorithm for aP4+ / aP5 devices (update version of CREA algorithm with accelerometer and magnetometer calibration)

Changed

• Export files user interface updated
• Visualisation menu interface updated

8.11.6.70    (27th Aug 2021)

Changed

• New Exports (Old versions moved to Legacy Exports)
  • Daily Summary Outcomes
  • Average Sumamry Outcomes
  • Whole recording Outcomes

8.11.5.64    (19th Oct 2020)

Fixed

• Adjust Time in Bed page slider adjustment

8.11.5.63    (12th Oct 2020)

Fixed

• Compatibility with pml files with older format

8.11.5.62    (9th Oct 2020)

Added

• Added .pal record file legacy export
• Added upright bouts export
• Added stepping bouts export

Changed

• Time in Bed colouring in sedentary bouts visualisation can now be turned on and off

Fixed

• Fixes and improvements to the CREA Time In Bed Algorithm

8.11.4.61    (25th Jun 2020)

Added

• Custom duration epochs csv export 

Changed

• User interface updates
• Varying cadence shown in events linear view

Fixed

• Stability and bug fixes

8.11.2.54    (17th Oct 2019)

Fixed

• EventsEx csv file export was disabled in previous version

8.11.2.53    (14th Oct 2019)

Added

• User logs for processing parameters used on exports 

Changed

• LAM8 data file interface updates

Fixed

• Stability fixes
• OSX login fixes
• Bug fix for activPAL4 data where high intensity upright activity triggered classification errors (New algorithm version: CREA v1.1)

8.11.2.52    (18th Sep 2019)

Fixed

• Browse button retains previous folder location
• Blank screen when double clicking on datx file
• Time in Bed date display issue – dates offset by one day on user time zones before UTC
• Time in bed export: Waking day before / after columns were offset by one day for files starting just before midnight

8.11.2.51    (5th Sep 2019)

Added

• Daily time in bed export csv
• Online help links to exports 

Changed

• Raw data export now simplified, and provides uncompressed and compressed exports

Fixed

• Time in Bed display issues
• Sign in fixes
• Minor export bug fixes

8.11.1.49    (10th Jul 2019)

Added

• Additional stepping data columns on daily summaries export

Fixed

• Minor bug fixes

8.11.1.48    (5th Jul 2019)

Fixed

• Time in bed algorithm fix – fixes misclassification of start of time in bed with multiple small duration rolling events
• Minor bug fixes

8.11.1.47    (20th Jun 2019)

Added

• CREA algorithm full release – enhanced version of standard PAL algorithm with addition of non-wear, upright correction, lying, cycling and seated transport classification
• Events linear day per row heatmap visualisation
• Week view spiral visualisation
• Time in bed adjustment interface
• 15s “Inclination and vector magnitude” csv export
• New graphical visualisation selection menu
• Quick export menu based on current view

Fixed

• Stability and bug fixes

8.10.8.32    (18th Dec 2018)

Added

• CREA algorithm (BETA) – including non-wear, upright correction, and lying classification
• Extended Events file csv export (BETA)
• Lying data visualisation (BETA)
• Wear time protocol is now editable in settings
• Time overflow bug correction on opening datx files
• Minimum sedentary and upright times now parameterised in settings

Fixed

• Minor visualisation fixes 
• Stability fixes

8.10.7.25    (23rd Oct 2018)

Fixed

• Windows 7 blank screen on some PCs

8.10.6.19    (9th Aug 2018)

Fixed

• Stability fixes

8.10.3.8    (27th Apr 2018)

Changed

• Basic usage enabled without sign in
• Valid day filter on spiral
• Daily summaries visualisation and pdf export

8.9.3.5    (9th Feb 2018)

Added

• Initial general release