Antenatal CareFS2NCT07677670
AI Blind-Sweep Ultrasound for Antenatal Screening by Non-Specialist Health Workers in Rural DR Congo
An observational study of Antenatal Care and Maternal Health, run by SOIK Corporation Sarl at 1 site in Democratic Republic of the Congo.
Trial summary
FS2 evaluates the diagnostic accuracy and implementation feasibility of an AI-assisted blind-sweep obstetric ultrasound (SPAQ E-con AI), operated by trained non-specialist health workers, for antenatal screening in rural Democratic Republic of the Congo. Read more about this study
- Who is it for?
- Ages 18 years and older, women onlyHealthy volunteers can take part
- Conditions the study is for
- Antenatal Care, Maternal Health, Gestational Age
- What is being tested?
- SPAQ E-con AI blind-sweep ultrasound
- How many people
- 3,000 participants
- Where
- 1 siteDemocratic Republic of the Congo
- Study dates
- 19 Jun 2026to 13 Jun 2027
- Phase
- Observational
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- Women only
- Healthy volunteers accepted
- Adult, Older adult
Study population: Pregnant women attending routine antenatal care at participating facilities or identified through community health worker (RECO) village outreach in the Kenge health zone, Kwango province, DRC.
Who may be able to join
- Pregnant women aged 18 years or older
- Identified at a participating facility routine ANC visit or RECO village outreach within the Kenge health zone catchment
- Written informed consent obtained
Who cannot join
- Emergency presentation
- Duplicate re-registration of an already-enrolled woman
- Lacking capacity to consent
- Planned relocation outside Kwango province during the study period
- Refusal of consent
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Democratic Republic of the Congo1 site, 1 recruiting
- Recruiting
Centre de Sante CBCO
Kenge, Kwango
Henoch Bulu, +243812268392, drhenochbulu@gmail.com
About this study
Official title: Diagnostic Accuracy and Implementation Feasibility of AI-Assisted Blind Ultrasound Sweep (SPAQ E-con AI) for Antenatal Screening by Non-Specialist Health Workers in Rural Democratic Republic of the Congo
FS2 evaluates the diagnostic accuracy and implementation feasibility of an AI-assisted blind-sweep obstetric ultrasound (SPAQ E-con AI), operated by trained non-specialist health workers, for antenatal screening in rural Democratic Republic of the Congo. Primary outcomes are gestational age mean absolute error (Trimester 2 and Trimester 3) with 95% confidence intervals and AI confidence calibration. The reference standard is manual measurement by a reference reader (early ultrasound first; manual BPD if unavailable; last menstrual period is not used). Planned enrollment is approximately 1,380: Batch 1 (closed, 80 enrolled) and Batch 2 (approximately 1,300), within an IRB-approved ceiling of 3,000. Early termination is permitted upon achievement of pre-specified analysis-plan thresholds. The study is a multi-center prospective Hybrid Type 1 Effectiveness-Implementation design and includes a pre-specified adaptive model-update (Batch 2 cut) plan following FDA PCCP and STARD-AI guidance.
Read the detailed description
Study conduct is organised in Batches. Batch 1 (Centre de Sante CBCO, Kenge health zone, Kwango province) enrolled 80 participants, of whom 78 had complete datasets, and is closed. Batch 2 is planned at approximately 1,300 participants. The confirmatory analysis cut is approximately 130 to 160 cases acquired with a model frozen before collection, comprising a core set of 80 to 100, an early-gestation enrichment of 25 to 30, and an upper-gestational-age enrichment of 25 to 30. Enrolment may stop early once the pre-specified confidence-interval criteria for the two primary gestational-age outcomes are met. The registered enrolment ceiling of 3,000 is unchanged.
Sites are facilities of the Kenge health zone, Kwango province, within the perimeter already approved in the protocol (up to 6 facilities plus 2 to 5 village outreach sites).
Eligibility follows the protocol: pregnant women aged 18 years or older. Multiple pregnancies are eligible.
Two sub-cohorts address the bounds of the gestational-age range. The early sub-cohort (crown-rump length 7 to 84 mm, approximately under 14 weeks) draws on the same source population as Cohort B-2 and is recruited through community health worker (RECO) village outreach and neighbouring health facilities; it is reported descriptively. The upper-bound sub-cohort (35 weeks or more) is a separate validation subset, recruited in parallel and analysed separately; sensitivity and specificity are reported, and positive and negative predictive values are not reported because prevalence in this subset is artificial.
The registered Trimester 3 estimation window (28 to 36 weeks) is unchanged. In Batch 2, point estimates are reported for 28 to 34 weeks, and 35 to 36 weeks is handled as "to be confirmed / refer". This is an operational reporting restriction, not a change to the registered window.
The AI model is identified and frozen before each Batch and recorded in a model and application version registry under a pre-determined change control plan. Results are reported by frozen version. AI inference is not used for clinical decision-making.
- Being tested
- SPAQ E-con AI blind-sweep ultrasound
- Keywords
- blind sweep ultrasound, artificial intelligence, point-of-care ultrasound, task-shifting, DRC
- Medical subject headings
- Placenta Previa
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
SPAQ E-con AI blind-sweep ultrasoundDiagnostic test
Smartphone-based 9-sweep obstetric ultrasound with AI estimation of gestational age, fetal presentation, and placenta location, operated by trained non-specialist health workers after 30-60 minutes of training. The AI model is frozen before each Batch and managed in a version registry under a pre-determined change control plan (PCCP); AI inference is not used for clinical decision-making.
| Study group | Role | What they receive |
|---|---|---|
| Cohort A | Natural enrollment / Description: Consecutive ANC attendees (natural prevalence) Receives: Diagnostic Test: SPAQ E-con AI blind-sweep ultrasound | |
| Cohort B-1 Placenta/malpresentation enriched | Enriched validation subset for placenta praevia and fetal malpresentation Receives: Diagnostic Test: SPAQ E-con AI blind-sweep ultrasound | |
| Cohort B-2 - Trimester 1 (CRL/GS) enriched | Enriched trimester 1 cases for CRL/GS gestational age models Receives: Diagnostic Test: SPAQ E-con AI blind-sweep ultrasound | |
| Cohort B-3 - Early gestation (CRL 7-84 mm) enriched | Early-gestation enrichment sub-cohort: crown-rump length 7-84 mm, approximately under 14 weeks of gestation. Drawn from the same source population as Cohort B-2 and recruited through community health worker (RECO) village outreach and neighbouring health facilities. Reported descriptively. Receives: Diagnostic Test: SPAQ E-con AI blind-sweep ultrasound | |
| Cohort B-4 - Upper gestational-age bound (>=35 weeks) validation subset | Validation subset at the upper bound of the gestational-age range (35 weeks of gestation or more), recruited in parallel with the main cohort and analysed separately. Sensitivity and specificity are reported. Positive and negative predictive values are not reported, because prevalence in this subset is artificial. Receives: Diagnostic Test: SPAQ E-con AI blind-sweep ultrasound |
What is being measured
The primary outcome is the main question the study is designed to answer.
Gestational age mean absolute error (MAE), Trimester 2 (14-27 weeks)
MAE in days vs reference standard, with 95% CI; target MAE ≤7 days and upper 95% CI ≤10 days
Measured: Through study completion, up to 12 months
Gestational age mean absolute error (MAE), Trimester 3 (28-36 weeks)
MAE in days vs reference standard, with 95% CI; target MAE ≤10 days and upper 95% CI ≤14 days
Measured: Through study completion, up to 12 months
AI confidence calibration - Expected Calibration Error (ECE)
Expected Calibration Error from the reliability diagram of AI confidence versus reference-standard agreement; target <=0.05
Measured: At Batch 1 closure, up to 8 weeks
AI confidence calibration - Brier score
Brier score of AI confidence versus reference-standard agreement; target <=0.20
Measured: At Batch 1 closure, up to 8 weeks
Secondary outcomes (10)
Trimester 1 gestational age MAE (CRL and GS models)
Integrated Cohort A T1 + Cohort B-2, N=30; CRL model MAE ≤5 days or GS model MAE ≤7 days
Measured: Through study completion, up to 12 months
Placenta praevia and fetal malpresentation sensitivity and specificity
Observed sensitivity/specificity with 95% CI (Clopper-Pearson) on enriched validation subset (Cohort B-1, target N=20-25); reported as observed values
Measured: Through study completion, up to 12 months
Inter-rater reliability of gestational age - Intraclass Correlation Coefficient (ICC)
ICC(2,1) between two independent readers for gestational age in days
Measured: During the inter-rater assessment window, up to 1 week
Inter-rater reliability of placenta praevia classification - Cohen's kappa
Cohen's kappa for placenta praevia (yes/no) between two independent readers
Measured: During the inter-rater assessment window, up to 1 week
Inter-rater reliability of fetal presentation classification - weighted kappa
Linear weighted kappa for fetal presentation category between two independent readers
Measured: During the inter-rater assessment window, up to 1 week
Acceptability - Acceptability of Intervention Measure (AIM) score
Mean AIM score (4-item, 5-point Likert) among health workers
Measured: Through study completion, up to 12 months
Feasibility - ultrasound throughput (scans per device per day)
Number of scans completed per device per day; target >=15
Measured: Through study completion, up to 12 months
Fidelity - protocol adherence rate (5-item checklist)
Percentage adherence on a 5-item fidelity checklist; target >=80%
Measured: Through study completion, up to 12 months
Penetration - proportion of eligible women screened
Percentage of eligible women in the catchment screened with AI ultrasound
Measured: Through study completion, up to 12 months
Sustainability - intention to continue use
Percentage of staff reporting intention to continue use at the end-of-study interview
Measured: At study completion, up to 12 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Jul 2026
- Study start19 Jun 2026
- Primary completion31 Dec 2026 (estimated)
- Study completion13 Jun 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Antenatal CareStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 3,000 participants (estimated)
Sponsor and investigators
- Lead sponsor
- SOIK Corporation Sarl
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Kuniyuki Furuta, Principal investigator, SOIK Corporation
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07677670
- Sponsor's protocol ID
- SOIK-FS2-2026
- Acronym
- FS2
- Status last verified
- Sep 2026
- First submitted
- 18 Jun 2026
- Last updated
- 15 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided