Customize Hub's UPL split rules (LENA SP only)
By default, LENA Hub splits the contents of the recorder at any pause that is longer than 60 minutes (3600 seconds). The resulting files are then processed separately. In most cases, the default setting is recommended (more information and rationale below).
If necessary, follow these instructions to customize your UPL split value or to disable splitting.
These instructions apply to LENA Hub version 4.0 and later. If you are running an older version of Hub, please first update your LENA Hub software.
Important information about SP only settings:
- Settings are specific to the individual computer. If you have more than one Hub, customize the settings on each installation.
- If your project uses multi-day mode devices, do not disable splitting. Doing so could create files that are too long to be processed, resulting in potential data loss.
- Customizations on the SP Program Settings tab apply only to recordings transferred for children enrolled in a LENA SP organization. Any changes to the default SP Program Settings are ignored for Start, Grow, and Home children. Recordings for Start, Grow, and Home children processed on this computer will always be split according to the default settings.
Prior to making changes, be sure you understand the purpose of UPL splitting and the consequences of changing the default settings.
The UPL is the compressed audio file that is analyzed, or "processed" using the LENA algorithms. LENA Hub creates the UPL file during recorder transfer.
Each UPL for a LENA SP child yields:
- one ITS file containing the processing results
- one daily bar for each core measure on the LENA Report, and corresponding hourly bars
- one percentile rank for each core measure on the LENA Report (if eligible based on duration, age, and quality checks)
- one AVA score (if eligibility criteria are met)
- one VP score (if eligibility criteria are met)
- one WAV file (if audio storage is enabled in SP Program Settings)
LENA Hub can break the recorder data into separate UPL files wherever the recording was stopped and later resumed.
The Split UPL Files setting governs whether a pause can result in separate UPLs. The UPL Split Time value is the pause duration that triggers a split.
After a split:
- The resulting UPL files are all assigned to the same child.
- The child's age is calculated separately on each UPL based on the recording start date.
- Each UPL is analyzed separately, as though it originated from a separate recorder transfer.
The standard setting creates separate UPLs at any pause of an hour or longer.
Splitting files at long pauses is recommended to ensure application of the correct algorithms, and to maintain the validity of percentile, AVA, and VP results.
- Splitting at recording boundaries bypasses problems that occur when a participant receives a device that already contains a small recording - typically an accidental test or demo recording from days, weeks, or months prior.
- Splitting the recordings into separate files ensures that the child's age is calculated appropriately for each recording date on the device. Child age is used to select processing algorithms, to run the AVA and VP analyses, and to generate percentiles for AWC, CTC, and CVC on files of sufficient duration.
- Splitting helps to ensure that the data resemble the 12-hour solid recordings in our normative sample as closely as possible. For example, if a subject records 4 hours a day over 4 days, the data may be very useful, but they should not compared to the 12-hr norms for AWC, CTC, and CVC.
All results are still displayed and exportable in LENA SP, regardless of duration or quality - nothing is automatically tossed out.
The user can manually hide and/or exclude any junk data that doesn't meet the project's criteria or that should have been erased prior to the intended recording.
1. Click on the wrench icon to open the Settings screen.
2. Click the SP Program Settings button.
3. Adjust UPL split settings
These two settings govern how pauses are handled. In most cases, the default settings are recommended:
- Split UPL Files = Yes
- UPL Split Time (in seconds) = 3600
To turn off UPL splitting, set the Split UPL Files toggle to No. If you choose not to split the UPLs:
- All data on the recorder will be processed as one recording, regardless of the number of days represented.
- Algorithms and normative information are applied to the entire contents according to the child's age at the onset of the first recording only.
- The LENA Report will show a single daily bar for each core measure, regardless of the number of days represented in the recording.
- The recording date displayed on the report and on the Recordings screen may not match your external data collection records, as it will reflect the onset of the first recording only.
- If filtering exports by date, you will need to refer to the date on the report, not the date of each subsequent recording.
- Reported percentiles for AWC, CTC, and CVC, as well as AVA and VP results, may not be valid, because long pauses represent a deviation from the data set on which the norms were created.
To customize the allowable pause length, set the Split UPL Files toggle to Yes. Then under UPL Split Time, enter the maximum allowable pause duration in seconds. (The conversion to hours and minutes is displayed just below.)