This is a multi-site, longitudinal study to evaluate the use of the SEM Scanner as an adjunct to clinical judgment for detection of early pressure ulcers in patients before clinical judgment using signs of pressure ulcers from skin assessments. longitudinal study to evaluate the use of the SEM Scanner as an adjunct to clinical judgment for detection of early pressure ulcers in patients before skin assessments.

All subjects are followed for a minimum of 6 days to a maximum of 21 days upon enrollment or until exit from the study . Enrolled subjects are assessed once daily throughout the follow-up period. Assessments are performed at the sacrum and both heels; if one or more locations are not assessable with the SEM Scanner, only the assessable locations are assessed. Each study site may include one or two wound care specialist (or a similarly trained clinician; the "Specialist") and one or two clinician/patient care provider(s) (the "Generalist") who perform assessments in the study.

Study assessments include (i) daily Risk Assessment and (ii) daily Skin Assessment performed by the Specialist blinded to the SEM readings; and (iii) daily SEM Scanner readings collected by the Generalist blinded to the Risk and Skin assessments. The outcome of interest is the diagnosis of a pressure ulcer by the Specialist using clinical judgment. The Specialist stages any diagnosed pressure ulcers according to NPUAP/EPUAP 2014 guidelines.

Note: If applicable, enrolled subjects continue to receive facility's standard of care practices for pressure ulcer preventive care. Participation in the study does not alter patient's standard of care.

This study involved two study objectives -

1. A primary objective to demonstrate the sensitivity and specificity of the SEM Scanner 200 in detecting early pressure ulcers before clinical judgment ("diagnose PU before clinical judgment").
2. A secondary objective to determine how early the SEM Scanner can detect signs before visually identified via clinical judgment ("time to detection").

Inclusion Criteria:

1. Greater or equal to 55 years of age

2. At risk of developing a pressure ulcer at time of enrollment as defined by one or more of the following:

   1. PU Risk Score - Braden < 15; Waterlow ≥ 10; or Norton ≤ 18
   2. Poor mobility; e.g., Braden mobility subscore ≤ 2; Waterlow mobility subscore > 2; Norton mobility subscore ≤ 2; or poor mobility according to clinical judgment (chair- or bed-bound)
   3. Poor nutrition; e.g., Braden nutrition subscore ≤ 2; Waterlow nutrition subscore > 2; or poor nutrition according to clinical judgment
   4. Medical procedure (e.g. surgery, x-ray, etc.) involving immobility and inability to change position lasting 4 hours or longer

3. Evaluable by the study team for a minimum of 6 consecutive days upon enrollment

4. Willing and able to provide informed consent (or by proxy)

Exclusion Criteria:

1. Unhealed (including newly diagnosed) pressure ulcer at any anatomical site at the time of enrollment
2. Broken skin at the sacrum and both heels that prevents collection of SEM Scanner readings from all three anatomical locations; possible assessment at only one or two locations is not grounds for exclusion
3. Moisture lesion or incontinence associated dermatitis at the sacrum
4. Physical, structural, or other limitations preventing assessments required in this study (e.g., suspected or actual injury preventing turning)
5. Presence of any condition(s) or injury(ies) which compromises the subject's ability to complete this study
6. Per clinical decision of the study Investigator, diminished decision-making capacity which might impact compliance or completion with study procedures
7. Patient modesty concerns on the part of the subject (or their proxy) that might impact collection of SEM Scanner readings at the anatomical location (heels and sacrum) to be assessed

189 subjects were enrolled but 7 subjects data were excluded from ITT analysis; non-analyzable data as per "valid Series" in the Statistical Analysis plan; three days of SEM scanner measurements with no more than one day missing between the three days of measurements and comprising no more than four observation days of SEM Scanner measurements.

A subject was included in the analysis when they had at least one "valid series" within 5 days of visual skin assessment identification of a pressure ulcer (6-21 observation days), or study exit when no pressure ulcer was identified.

All enrolled 189 subjects were scanned using the SEM scanner and Visual Skin Assessments. AE events could not be distinguished by arm. All SAE's (clinicaltrials.gov definition) and any device related AEs were defined as "SAEs" consistent with the non-significant risk classification/indication for the device. AEs (clinicaltrials.gov definition) and unrelated to the device were defined as AE's. SAE, AE events are reported in enrolled 189 subjects as opposed to ITT analysis for 182.

It was essential that both assessing teams' results were blinded to each other. Blinding between the "Specialist" and the "Generalist" teams was successfully upheld in this study. Data entry was structured in a manner restricting access based on roles and responsibilities defined in the study. The Study Investigators and Study Coordinators ("gate-keeper") were also diligent about ensuring blinding between the two assessing teams. The Principal Investigator or designated Co-Investigator were unblinded to the results of each study subject at the time of eCRF approval or exit for that subject. Prior to interim analysis, BBI's management team were also restricted to access the study's database, and thus were blinded to daily results. This further assures that no bias is introduced by the study sponsor to data collection.