Feasibility of Vital Sign Assessment by Community Health Workers During Antenatal Care Community Outreach
Conditions: Pregnancy Related
Sponsor: Centre for Infectious Disease Research in Zambia

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Feasibility of Vital Sign Assessment by Community Health Workers during Antenatal Care 
Community Outreach 
 
 
Protocol version 1.1 
14 April 2023 
 
 
 
  
 
 
 
 
 
 
 
Investigators 
1. Albert Manasyan, MD, MPH 
2. Anjali Sharma, DrPH 
3. Assumpta Nantume, MSc 
 
 
 
Study Sponsor: 
NeoPenda PBC. 
Wellcome Trust Flagship Innovations  

2 
 
Table of abbreviation 
 
PR 
 
Pulse Rate 
RR 
 
Respiratory Rate 
IRB 
 
Institutional Review Board 
UNZA  
University of Zambia 
CHW  
Community Health Worker 
LMIC  
Low- and Middle-Income Country  
WHD  
Wearable Health Device 
ANC  
Antenatal Care 
FDA  
Food and Drug Administration 
BP 
 
Blood Pressure 
PPG 
 
Photoplethysmograph 
SPO2  
Blood Oxygen Saturation 
IDI 
 
In-Depth Interviews 
RA 
 
Research Assistant 
NHRA  
National Health Research Authority 
ZAMRA 
Zambia Medicines Regulatory Authority 
 
 
 

3 
 
Table of Contents 
Table of abbreviation ...................................................................................................................... 2 
1.0 Introduction .............................................................................................................................. 4 
2.0 Statement of the problem ........................................................................................................ 6 
3.0 Rationale/Justification .............................................................................................................. 7 
4.0 Theoretical/conceptual framework .......................................................................................... 7 
5.0 Literature review ....................................................................................................................... 7 
6.0 Research questions ................................................................................................................... 8 
7.0 Specific Aims ............................................................................................................................. 8 
8.0 Methodology ............................................................................................................................. 8 
9.0 Ethical considerations ............................................................................................................. 11 
10.0 References ............................................................................................................................ 13 
 
 
 

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1.0 Introduction  
Continuous vital sign monitoring is a basic tenet of specialized care in the developed world that 
is vastly underutilized during hospital or clinic admissions or outpatient routine visits in most 
low-and-middle income countries (LMICs). Despite the positive outcomes associated with vital 
sign monitoring (i.e., increased survival-to-discharge rates, lower complication rates and shorter 
length of stay in hospital),1 the prohibitive costs of conventional patient monitors and the 
difficulty in maintaining complex medical equipment limit its practice in the developing world.  
Wearable health devices (WHDs) are increasingly helping people better monitor their health 
status both at an activity/fitness level for self-health tracking and at a medical level providing 
more data to healthcare providers to increase the potential for early diagnosis and guidance of 
treatment. Key advancements in technology are enabling the creation of smaller computers than 
ever before; allowing wearable technology to incorporate miniaturized systems to enhance the 
quality and convenience of patient care.1 Advances in materials science, chemical analysis 
techniques, equipment design and manufacturing methods have further laid the foundation for 
the continuous evolution of wearable systems over the years.2 
 
WHDs when properly designed, implemented and adopted can provide ample benefits for 
healthcare providers and patients. Wearable technologies like Apple watch, Fitbit, Jawbone, ViSi 
Mobile and Vital Connect wireless patch have been used in tracking personal physiological and 
biological parameters for routine activity performance and/or clinical monitoring.3,4 These 
devices collect data such as heart rate, stress levels, obesity, oxygen saturation, blood pressure 
and calories; and serve a broad range of use cases from newborn to elderly patients in different 
settings such as hospitals, nursing homes and homecare settings.  
 
Measurement of vital signs in both in- and out-patient departments and during community 
outreach activities is necessary to assess the clinical situation of the patient and capture early 
warning scores for deterioration. The currently practice in most LMICs is for a clinician to take 
routine vital sign measurements intermittently and manually record these on a clinical chart. 
However, this leaves a lot of room for missed detection of early warning scores. Delays in 
diagnosing clinical deterioration prevent clinicians from taking corrective actions and are 
associated with increased complication rates and mortality. The use of wearable devices for long 
term monitoring is intended to provide instant diagnosis of acute events that will in turn lead to 
more effective and timely treatment of patients.5 Furthermore, the situation becomes more dire 
during community outreach activities (i.e., child health week, community ANC outreach, etc.), 
which are usually conducted by limited clinicians and several community health workers 
(CHWs). 
 
In contrast to the traditional monitoring devices that have been in use in clinical settings, WHDs 
may be more suited to the constraints of low-resources settings. Conventional medical equipment 
frequently fail in health facilities in LMICs due to complex design and specifications, and 
environmental constraints including power instability, internet access, space limitations and 
availability of spare parts. This calls upon the need for more feasible innovations to improve on 
the quality of care for people living in LMICs. WHDs offer a promising solution. 
 

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Currently, due to lack of medical supplies, most ANC clinics – within the health facilities or 
during outreach activities – do not monitor for vital signs and blood pressure among pregnant 
women. While many devices exist, their ease of use and high-cost, including maintenance costs, 
hinder screening and monitoring programs in low resource settings. Accurate and low-cost vital 
sign monitoring devices are required to improve identification and treatment of women with 
danger signs during their routine ANC visits. To meet the growing demand for vital sign 
monitors during the COVID-19 pandemic, Neopenda has adapted an affordable, wearable, 
wireless vital sign monitoring solution (neoSpotTM), that measures temperature, respiration rate, 
blood oxygen saturation, pulse rate, and blood pressure.  
 
1.1 Previous research on the neoSpotTM product 
The neoSpotTM system is a new prototype in the series of vital sign monitors designed by 
Neopenda. The product is an iteration of the current vital signs monitor, neoGuardTM, which 
provides continuous measurement of pulse rate (PR), peripheral blood oxygen saturation (SpO2), 
respiratory rate (RR) and temperature to patients in tertiary care settings. The neoSpotTM system 
has been developed to capture instantaneous readings in settings such as community outreaches 
or lower-level health facilities, where reliable vital sign measurement equipment is not readily 
accessible. Since the new product will comprise of similar hardware and algorithms to its 
precursor, neoGuardTM, it is expected to perform at the same level of accuracy for measurement 
of PR, SpO2, RR and temperature. Measurement of an additional parameter, blood pressure (BP), 
is in the early stage of development and will add substantial value to the previous product. The 
data generated from this study will help in the final integration of BP measurement to the 
neoSpotTM system.While this will be the first field study on neoSpotTM itself, related research has 
been conducted on the precursor system, neoGuardTM, as detailed below. Our path to evaluating 
and developing neoSpotTM into a commercial product will follow a similar pathway. 
 
Table 1. Research history of Neopenda’s wearable vital signs monitors 
 
Timeline 
Location 
Device 
Version 
Description 
Purpose 
Sample 
Size 
Status 
Jul 2019 
TMC, 
Boston, MA, 
USA 
neoGuard 
V1.0 
Pilot study 
Evaluate and 
refine signal 
quality 
22 
neonates  
Complete 
Oct 2019 
Jinja RRH 
neoGuard 
V2.0 
Pilot study 
Evaluate 
preliminary 
accuracy 
27 infants 
and stable 
neonates 
Complete 
Sep 2020 
Clinimark 
Laboratories 
neoGuard 
V3.0 
Accuracy 
study 
Validation of 
final accuracy  
15 healthy 
adults 
Complete 
Oct 2020 
UCSF 
Hypoxia Lab 
neoGuard 
V3.0 
Accuracy 
study 
Validation of 
final accuracy  
15 healthy 
adults 
Complete 
Feb 2021 
Jinja RRH 
neoGuard 
V3.0 
Feasibility 
study 
Evaluate 
preliminary 
accuracy 
30 adult 
patients 
Complete 
Mar-May 
2021 
Kenya 
neoGuard 
V3.0 
Feasibility 
study 
Evaluate 
feasibility and 
efficacy  
172 
neonates 
Complete 

6 
 
Mar-May 
2022 
Nigeria 
neoGuard 
V3.0 
Feasibility 
study 
Evaluate 
feasibility and 
efficacy  
~225 
neonates 
Ongoing 
Apr 2022 
– Apr 
2023 
Kenya 
neoGuard 
V3.0 
Interrupted 
time series 
study 
Evaluate clinical 
impact and cost-
effectiveness 
~3,000 
neonates 
Ongoing 
Jun-Sep 
2022 
Zambia 
neoSpot 
V1.0 
Feasibility 
study 
 
~100 
pregnant 
women 
Submitted 
for IRB 
approval  
V3.0* - these are commercial equivalent units 
  
2.0 Statement of the problem  
Few innovations are currently available to help overburdened clinicians and community health 
volunteers better manage the high quantity of patients. In the neoSpot solution, researchers are 
taking a known and proven science of clinical vital signs monitoring, and re-imagining it for the 
users and the constraints of low-resource environments. The current practice at most ANC clinics 
in LMIC settings is intermittent, manual measurement of vital signs or blood pressure. Nurses 
and Community Health Volunteers must manually count heart beats or breaths—at best every 
few hours—or share the few available, functioning devices, such as pulse oximeters, which only 
intermittently measure oxygen saturation and pulse. This practice is insufficient for early 
detection of danger signs and optimal management of critical care patients. 
Furthermore, gold standard monitors used in the U.S. and other high-resource areas, such as from 
Covidien, Masimo or Philips, are prohibitively expensive, inappropriately designed, and 
challenging to maintain or repair. They fail to meet unique sets of environmental constraints such 
as unstable power supply, lack of internet access, and heat & humidity. If donated to a low-
resource environment, they quickly fail or end up obsolete within short periods of use. Existing 
products in the global health space do not meet the need for continuous monitoring in the clinical 
setting (e.g. Lifebox pulse oximeter), only measure 1 or 2 parameters (e.g. BempuTemp Watch 
and NeMoCare) and/or are geared toward diagnosing specific conditions (e.g. pneumonia 
diagnostics like the Philips CHARM). 
Neopenda’s solution intends to improve the quality of patient care over the standard-of-care and 
addresses the unmet need for a feasible way to monitor multiple key vital signs. The neoGuardTM 
product is designed to operate in dynamic clinical environments with space constraints, 
unreliable power supply and limited numbers of health staff. At less than a 1/10th of the average 
cost of conventional patient monitors ($230 vs. $2,500), the neoSpotTM technology provides and 
affordable and sustainable vital sign monitoring solution. The wearable band is bio-compatible, 
reusable and easy to sterilize, ensuring that there are no additional costs spent on single-use 
accessories.  
NeoSpotTM has been developed and tested with feedback from more than 100 health workers 
with varying levels of clinical expertise and technical prowess to ensure that it is intuitive to a 
wide range of users including lower skilled personnel like nursing assistants and community 
health workers in remote settings. This human-centered design approach has been used to 
preempt the challenge of usability that can occur when transitioning new technologies to diverse 
users in different cultural contexts. 

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3.0 Rationale/Justification 
 
Many novel interventions are introduced to LMICs with little-to-no evidence of their successful 
performance, applicability, effectiveness, and feasibility and acceptability by the providers. 
There is need for robust testing and evaluation of innovations to ensure that they serve their 
intended purposes before they are introduced into common practice. The justification for this 
study is the need to generate evidence of feasibility and acceptability for neoSpotTM on pregnant 
women, so as to inform any changes or considerations for its use in LMIC settings. This 
proposed study is unique, impactful, and scalable given the immediate clinical application by 
CHWs during community ANC visits. 
If the NeoSpot device shows to be feasible and acceptable for use by CHWs and by pregnant 
women, there would be sufficient evidence to support the use of the device to measure vital signs 
and blood pressure among pregnant women.  This study has the potential to improve access vital 
signs measurements during both community and clinic activities as it would increase 
identification and improve treatment of pregnant women with danger signs such as 
eclampsia/pre-eclampsia, fever, etc. in low-resource settings and would serve the larger aim of 
reducing maternal and neonatal morbidity and mortality.   
4.0 Theoretical/conceptual framework 
This study is a feasibility trial, which is designed to demonstrate the feasibility and acceptability 
of this novel platform when used by community health workers (CHWs) on pregnant women to 
check their vital signs during community ANC outreach activities. 
5.0 Literature review  
Patient vital signs monitoring is key to disease management and timely intervention. 
Measurement of vital signs in in- and out-patients is necessary to assess the clinical situation of 
the patient and to detect clinical deterioration at an earlier stage, which allows clinicians to take 
corrective actions.7 WHDs like the ViSi Mobile Wireless Sotera and Health Patch Vital Connect 
that can be used for continuous collection of physiological data have been cleared by the US 
Food and Drug Agency (FDA) for home and hospital use. In a 2017 feasibility study, Weenk et 
al. concluded that both ViSi Mobile and Health Patch were promising for continuously 
monitoring vital signs in hospitalized patients, if the frequency and duration of artifacts could be 
minimized. The devices were well received and comfortable for most patients.3 
In a subsequent study, ViSi Mobile and Health Patch were tested regarding Modified Early 
Warning Scores (MEWS) calculation and compared to nurse measurements and detection of high 
MEWS in periods between nurse observations; findings suggested that the wearable devices 
were more accurate than nurses’ observations.9 
A few other studies about continuous monitoring with wearable technologies on general ward 
and ICU patients have been published. Martine et al. validated the accuracy of a wireless patch 
sensor to measure heart and respiratory rate in postsurgical patients at high risk for 
complications. The novel patch showed high accuracy for measurement of heart rate but 
accuracy for respiratory rate was outside acceptable limits.10In a feasibility study on wearable 
biosensor devices carried out in Rwanda, researchers observed that wearable devices could be 
feasibly implemented and that the units provided accurate vital sign measurements in critically ill 
paediatric and adult patients with sepsis.11 

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Results from a 2018 study carried out by Downey et al. showed that patients on the surgical ward 
found the monitoring device to be acceptable in terms of comfort and perceived an enhanced 
sense of safety.12Pavic et al. noted that remote monitoring of health care status in palliative 
cancer patients with a limited life expectancy was feasible and patients were able to handle the 
smartphone and sensor- equipped bracelet.13An early evaluation of the agreement between the 
SensiumVitals digital patch and a widely used clinical monitor was conducted between Oct 2009 
- Jul 2010. Overall agreement for respiration and heart rate measurements between digital patch 
and clinical monitor was satisfactory.14 
Multiple studies have been conducted on the Bio-Beat medical smart-monitoring technology, 
demonstrating that in all of the tested statistical parameters, the Bio-Beat application is almost 
equal to the gold standard device, with a correlation of 98.9%.15 
In summary, the published literature on WHDs suggests that these innovative technologies and 
digital health systems may offer a viable solution towards an affordable, sustainable and scalable 
model of patient monitoring in resource-limited settings.  
6.0 Research questions  
1. Is the NeoSpot a feasible, acceptable, and easy to use device when used by CHWs during 
community ANC outreach activities? 
2. Can photoplethysmograph (PPG) sensor data from NeoSpot be used to develop an accurate 
and reliable blood pressure algorithm? 
7.0 Specific Aims  
Aim 1: To describe the feasibility, acceptability, ease of use, and perceived confidence of 
pregnant women and CHWs to use the NeoSpot device during community ANC outreach 
The novel test device, NeoSpot will be used by 12 CHWs during community ANC 
outreach activities to measure vital signs among pregnant women in Lusaka, Zambia. Through 
in-depth interviews (IDIs), we will determine and feasibility, acceptability, and ease of use, 
including design feedback, of the device by 12 CHWs and 12 pregnant women. 
 
Aim 2: To obtain raw PPG data from the prototype NeoSpot device which will be used in 
the development of an accurate and reliable blood pressure algorithm. 
During community ANC outreach activities, CHWs will take readings with the NeoSpot 
device from 125 pregnant women. The raw PPG sensor data will be used to train an autonomous 
machine learning model to extract arterial blood pressure systolic and diastolic values. 
8.0 Methodology  
Study Design  
The proposed study is a pilot feasibility trial to be implemented at Kanyama  1st Level Hospital 
and its wider catchment area among a prospective cohort of pregnant women during community 
ANC outreach activities.  The test device, NeoSpot, will be used by CHWs and will monitor vital 
signs and blood pressure in each participant.   
The neoSpotTM device is a 5-in-1 wearable vital signs monitor designed to measure temperature, 
pulse rate (PR), respiratory rate (RR), blood oxygen saturation (SpO2) and blood pressure. It is 
currently under the final stages of development by Neopenda, PBC (Chicago, IL, USA) under 
international medical device standards and for feasibility in low-resource settings, including: 

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low-power design, safe re-usability, ruggedness, portability, and ease of use. The device weighs 
approximately 15 grams and measures 42 x 36 x 14 mm. It contains two non-invasive sensors: an 
optical reflectance pulse oximeter and a digital temperature sensor. These sensors measure 
signals from the surface of the patient’s skin, and algorithms within the device calculate the pulse 
rate, respiratory rate, SpO2, blood pressure and temperature. The device will be synced with a 
smartphone, which will be provided to the CHWs by the study. 
The device is made of medical grade polyetherimide plastic and can be worn through an 
adjustable band. The bands are made of medical-grade silicone rubber. The devices are wireless 
and powered by medically-certified rechargeable batteries. The pulse rate, respiratory rate, 
temperature, blood pressure and oxygen saturation data are recorded and transmitted to an app on 
a smart phone. Upon final validation and field testing, Neopenda will pursue CE mark 
certification for the neoSpotTM technology.  
 
 
 
 
 
 

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Study site and settings 
We propose that this prospective pilot feasibility study take place at the Kaynama 1st Level 
Hospital wider catchment area in Lusaka, Zambia. The area records around 10,000 deliveries a 
year, therefore, we are confident that we will screen 125 pregnant women in our stated period. 
 
Study Population 
Aim #1 
Study participants for the qualitative aim of the study will be comprised of 12 Community 
Health Workers (CHWs) who have used the NeoSpot device during routine government 
community ANC outreach activities. All 12 CHWs who consent will undergo in-depth 
interviews (IDIs) in addition to 12 pregnant women who have consented to participate in Aim #2 
of the study (below). Study participants meeting the following inclusion and exclusion criteria 
will be enrolled: 
 
Inclusion criteria 
1. CHWs who have used the NeoSpot device, or  
2. Pregnant women who have experienced the device under Aim #2 
2. 18+ years of age 
3. Willing to consent 
 
Exclusion criteria 
1. Pregnant women not enrolled under Aim #2 below 
2. Unable to consent 
 
Aim #2 
Study participants will be pregnant women recruited during the community ANC outreach 
(n=125) on the following inclusion and exclusion criteria: 
Inclusion criteria 
1. Pregnant 
2. 18+ years of age 
3. Willing to consent 
 
Exclusion criteria 
1. Unable to consent 
2. Not pregnant 
3. Age below 18 years 
 
Sample Size 
Aim #1: For the qualitative aim of this pilot study, 12 CHWs who have used the NeoSpot device 
and 12 pregnant women who have been enrolled into the study under Aim #2 (below) will be 
approached and, if consented, enrolled into the study. A total of 24 IDIs will be conducted 
among the target population. The sample size may be increased if saturation is not reached using 
this sample size. 
 
Aim #2: Twelve CHWs will be trained in the use of the NeoSpot and given the device to use 
during outreach activities. Potential study participants (i.e., pregnant women) will be approached 

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during the community ANC outreach activities. If interested, study staff will then discuss the 
study procedures, risks, and benefits in detail in Nyanja, Bemba, or English based on the study 
participant’s preference. Should they be interested in the study, they will be consented.  
Following enrollment, the CHWs will measure the pregnant woman’s vital signs and her blood 
pressure. A total of 125 study participants will be enrolled. 
 
Study Procedures 
Study hired Research Assistants (RAs) will approach potential study participants for both 
study aims and consent them for study participation. Following enrollment, for Aim #1, CHWs 
and pregnant women will undergo IDIs in a safe and secure location. IDIs will last 
approximately 1 hour and they will be conducted in the preferred language of the consented 
study participant. All study participants will exit the study following the IDI. For Aim #2, study 
staff will measure their vital signs and blood pressure using the NeoSpot, which data will be 
automatically stored into the smartphone provided by the study. Results of the vital signs and the 
blood pressure will also be shared with the clinical treatment team following screening.  The 
treating clinicians will notify the patient of the results and, if required, refer the pregnant women 
for appropriate care according to local standard of care. All study participants under Aim #2 will 
exit the study following this stage. 
 
Data Collection 
All data for Aim #1 will be recorded on a study audio recorder and then translated and 
transcribed onto a word document by a study team member. Once it is transcribed and has been 
reviewed for completeness, the audio recording will be destroyed.  
For Aim #2, PPG data will be automatically collected and stored by the NeoSpot directly 
into the smartphone, without the use of data collection tools. It will be stored on smartphones 
provided to the CHWs by the study. Following data storage, PPG data will be used to develop an 
accurate and reliable blood pressure algorithm for future piloting. Confidentiality of patient 
identifiers will be protected by using a patient identification key that will be stored separately 
from the data set.  Each study participant will be assigned a unique study identification number. 
The database will be password protected, accessible only to the study PI and data analyst. 
 
Data Analysis 
Aim #1: We will conduct 24 IDIs with pregnant mothers (12) and CHWs (12) from the study 
sites. Sample size will be increased if thematic saturation is not reached. The study RA will 
conduct a total of 24 IDIs, among 12 purposively selected pregnant women from Aim #2 and 12 
CHWs. IDIs will be audio-recorded, transcribed, and translated into English prior to thematic 
analysis using NVivo 9.0 (QSR International, Australia). We will conduct hybrid analysis using 
inductive reasoning to identify themes and deductive reasoning based on the suitability, 
feasibility and acceptability (SFA) framework. 
 
Aim #2: PPG data will be extracted from the database and used to further develop a reliable and 
accurate blood pressure algorithm, which will be piloted in the near future.   
9.0 Ethical considerations 
There will be no obligation to participate in the study, and informed consent will be 
obtained from each participant who chooses to enroll.  There is minimal risk for patients 

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included in this study.  Vital signs and blood pressure testing is non-invasive, and achieved by 
placing a sensor on the skin.  In this study, the NeoSpot device will be in place on the skin for 
<1minute making the risk for harm to the skin very low. Pregnant women with abnormal vital 
signs and blood pressure will be referred for further clinical assessment and treatment, which 
will be provided by the health facility at no cost to the family. The risk of these outcomes is 
balanced by the benefit of detecting danger signs in a pregnant women during ANC community 
outreach activities.   
We will work hard to protect personal and health information collected in the study as 
described above. Like all studies there is a small risk that personal or health information could 
become known to others and this could cause harm to the study participants.  To prevent this, 
research records will be kept confidential in a lockable cabinet to the maximum extent permitted 
by law.There may be no direct benefit to study participants. In the case that a danger sign, a 
benefit will be that we can communicate this finding with the pregnant woman’s healthcare 
provider so that she can receive appropriate treatment and additional testing if needed. 
The study protocol will undergo review and approval by local (UNZA-BREC, NHRA, 
and ZAMRA) and international (University of Alabama at Birmingham IRB) regulatory 
authorities. There are no direct costs to study participants.  Participants will receive 
compensation for their time in the form of cash valued at 100 ZMK. 
 
 

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