(124 days)
Not Found
No
The device is a laboratory assay kit that uses an immuno-turbidimetric method to measure D-dimer levels. The summary describes a chemical reaction and photometric measurement, not AI/ML algorithms. While the intended use mentions a clinical pretest probability (PTP) assessment model, the device itself is the assay kit, not the model.
No
The device is an in-vitro diagnostic test intended for quantitative determination of D-dimer to help exclude pulmonary embolism (PE) and deep venous thrombosis (DVT). It does not directly treat or prevent a disease.
Yes
This device is an immuno-turbidimetric assay for the quantitative determination of D-dimer in venous plasma, intended for use in conjunction with a clinical pretest probability assessment model to exclude pulmonary embolism (PE) and deep venous thrombosis (DVT). This directly indicates its use in diagnosing or ruling out these conditions.
No
The device description clearly states it is a "kit" containing vials of buffer and microlatex particles, which are physical components, not software. The test principle is based on a chemical reaction and photometric measurement, requiring hardware (analyzers) to function.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Intended Use: The intended use explicitly states it's an "immuno-turbidimetric assay for the quantitative determination of D-dimer in venous plasma... for use on STA-R®, STA Compact® and STA Satellite® analyzers by professional laboratory personnel." This describes a test performed on a biological sample (venous plasma) outside of the body to provide information about a patient's health status (D-dimer levels).
- Device Description: The description details the reagents (Tris buffer, microlatex particles coated with antibodies) and the test principle (antigen-antibody reaction leading to turbidity measured by photometry). This is consistent with the components and methodology of an in vitro diagnostic test.
- Anatomical Site: The "Not applicable. No direct patient contact." further supports that the test is performed on a sample taken from the patient, not directly on the patient's body.
- Intended User / Care Setting: The intended users are "professional laboratory personnel" in a "Hospital Laboratory or other Health Care Laboratory," which are typical settings for performing IVD tests.
- Performance Studies: The description of clinical studies involving testing patient samples (plasma) to evaluate the device's performance in diagnosing or ruling out conditions (DVT) is characteristic of the validation required for IVD devices.
- Predicate Device(s): The mention of predicate devices like "VIDAS® D-Dimer Exclusion™" (K040882) which are known IVD devices, further confirms the classification of this device.
All these elements align with the definition and characteristics of an In Vitro Diagnostic device.
N/A
Intended Use / Indications for Use
The STA® - Liatest® D-Di kit is an immuno-turbidimetric assay for the quantitative determination of D-dimer in venous plasma (3.2% sodium citrate) for use on STA-R®, STA Compact® and STA Satellite® analyzers by professional laboratory personnel. The STA® - Liates® D-Di is intended for use in conjunction with a clinical pretest probability (PTP) assessment model to exclude pulmonary embolism (PE) and deep venous thrombosis (DVT) in outpatients suspected of PE or DVT.
Product codes
DAP
Device Description
STA® - Liatest® D-Di kit contains: 6 x 5-ml vials of ready-for-use Tris buffer and 6 x 6-ml vials of a suspension of microlatex particles coated with two different mouse monoclonal anti-human D-dimer antibodies (8D2 and 2.1.16) stabilized with bovine albumin.
The test principle is based on the change in turbidity of a microparticle suspension that is measured by photometry. A suspension of latex microparticles, coated by covalent bonding with monoclonal antibodies specific for D-dimer is mixed with the test plasma for which the D-dimer level is to be assayed. An antigen-antibody reaction takes place, leading to an agglutination of the latex microparticles which causes an increase in turbidity of the reaction medium. This increase in turbidity is reflected by an increase in absorbance, the latter being measured photometrically. The increase in absorbance is a function of the D-dimer level present in the test sample.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
Not applicable.
No direct patient contact.
Indicated Patient Age Range
Not Found
Intended User / Care Setting
professional laboratory personnel.
Hospital Laboratory or other Health Care Laboratory.
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
A clinical multi-center study (16 sites over the United States, Europe and Canada), conducted according to CLSI H59-A, was performed to demonstrate the ability of STA® - Liatest® D-Di to safely rule-out DVT by using samples of prospective, consecutive, ambulatory outpatients (presenting at the emergency unit or outpatient clinic) suspected of having venous thromboembolism (VTE).
The study population was recruited from prospective, ambulatory outpatients suspected of having DVT. After consenting, these patients were evaluated using the Wells score as pretest probability (PTP) model:
- Patients with low or moderate PTP were considered for D-dimer testing:
- those with positive D-dimer result were considered for an imaging procedure ●
- those with negative D-dimer result were considered as not having DVT and . assigned to a three month follow up.
- Patients with high PTP were considered for an imaging procedure and not included in the study's primary analyses.
D-dimer assays were carried out using STA® - Liatest® D-Di on fresh plasma samples or on frozen plasma samples tested within 30 days of blood collection.
For primary efficacy analysis the population of interest was limited to patients with a PTP result low or moderate. In this group, only patients with a negative D-dimer result had a follow up call or visit at 3 months.
Summary of Performance Studies
A clinical multi-center study (16 sites over the United States, Europe and Canada), conducted according to CLSI H59-A, was performed to demonstrate the ability of STA® - Liatest® D-Di to safely rule-out DVT.
980 samples of patients with a low or moderate PTP were included in the primary efficacy analyses (79 suspects of DVT and PE and 901 suspects of DVT only).
Of the 980 samples, 85 were from DVT positive and 895 from DVT negative patients.
The overall prevalence of DVT (low and moderate PTP patients with positive imaging) in the prospective study population was 8.4 % with 6.0 % in the US population and 9.8% in the European/Canadian ("out of US") population.
Primary efficacy analyses of the study included calculation of two co-primary parameters: Negative Predicted Value (NPV) and Sensitivity which were tested versus four (4) performance goals-two using 95 % two-sided confidence intervals (CI) and two versus point estimates.
All the efficacy parameters with upper and lower limit of 95 % confidence intervals (CI) were calculated in the overall study population, and separately for the US population and the "out of US" population with the STA® - Liatest® D-Di clinical cut-off of 0.50 µg/ml (FEU) in the (low + moderate) PTP group of patients.
Overall Study Population (n=980):
Sensitivity (95 % CI) = 100% (95.8% - 100%)
Specificity (95 % CI) = 55.2% (51.9% - 58.5%)
NPV (95 % CI) = 100% (99.3% - 100%)
PPV (95 % CI) = 17.5% (14.2% - 21.2%)
US Prospective Study Population (n=369):
Sensitivity (95 % CI) = 100% (84.6% - 100%)
Specificity (95 % CI) = 58.2% (52.8% - 63.5%)
NPV (95 % CI) = 100% (98.2% - 100%)
PPV (95 % CI) = 13.2% (8.4% - 19.3%)
Out of US Study Population (n=611):
Sensitivity (95 % CI) = 100% (94.3%-100%)
Specificity (95 % CI) = 53.3% (49.0%-57.5%)
NPV (95 % CI) = 100% (98.7%-100%)
PPV (95 % CI) = 19.7% (15.5%-24.5%)
This study demonstrates that the STA® - Liatest® D-Di is effective in excluding deep venous thrombosis (DVT) in patient with a low or moderate PTP and a D-dimer level
§ 864.7320 Fibrinogen/fibrin degradation products assay.
(a)
Identification. A fibrinogen/fibrin degradation products assay is a device used to detect and measure fibrinogen degradation products and fibrin degradation products (protein fragments produced by the enzymatic action of plasmin on fibrinogen and fibrin) as an aid in detecting the presence and degree of intravascular coagulation and fibrinolysis (the dissolution of the fibrin in a blood clot) and in monitoring therapy for disseminated intravascular coagulation (nonlocalized clotting in the blood vessels).(b)
Classification. Class II (performance standards).
0
Image /page/0/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. Inside the circle is an abstract symbol that resembles a stylized human figure or a group of people in profile.
Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002
December 10, 2016
Diagnostica Stago c/o Carlo d'Alessandro Director, Quality and Regulatory Donawa Lifescience Consulting Piazza Albania, 10 00153 Rome, Italy
Re: K162227
Trade/Device Name: STA® - Liatest® D-Di Regulation Number: 21 CFR 864.7320 Regulation Name: Fibrinogen/fibrin degradation products assay Regulatory Class: Class II Product Code: DAP Dated: November 7, 2016 Received: November 9, 2016
Dear Mr. d'Alessandro:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food. Drug. and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21. Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21
1
CFR Part 807); labeling (21 CFR Parts 801 and 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Division of Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address
http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to
http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.
You may obtain other general information on your responsibilities under the Act from the Division of Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address
http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.
Sincerelv.
Leonthena R. Carrington -S
Leonthena R. Carrington, MS. MBA, MT(ASCP) Director Division of Immunology and Hematology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health
Enclosure
2
Indications for Use
510(k) Number (if known)
Device Name STA® - Liatest® D-Di
Indications for Use (Describe)
The STA® - Liatest® D-Di kit is an immuno-turbidimetric assay for the quantitative determination of D-dimer in venous plasma (3.2% sodium citrate) for use on STA-R®, STA Compact® and STA Satellite® analyzers by professional laboratory personnel. The STA® - Liates® D-Di is intended for use in conjunction with a clinical pretest probability (PTP) assessment model to exclude pulmonary embolism (PE) and deep venous thrombosis (DVT) in outpatients suspected of PE or DVT.
| Prescription Use (Part 21 CFR 801 Subpart D) | |
|---|---|
| Over-The-Counter Use (21 CFR 801 Subpart C) |
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Type of Use (Select one or hoth, as annlicable)
3
Image /page/3/Picture/0 description: The image features the logo for Stago, a company specializing in in-vitro diagnostics. The logo consists of the word "Stago" in a red, serif typeface, positioned below a stylized graphic. The graphic is composed of two abstract shapes: one in a reddish-brown hue and the other in a muted gray-brown, arranged to suggest a sense of movement or flow.
510(k) Summary
| Submitter Information: | Diagnostica Stago
3, Allée Thérésa
92600 Asnières sur Seine, France
Contact name: Mr. Arnaud Berthier
Market Access Operating Director
Tel: +33 1 46 88 21 01 (main)
+33 6 85 92 30 82
Fax: +33 1 47 33 64 60 |
|--------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Date of Submission: | 05 August 2016 |
| Application Correspondent
and Contact Person: | Mr. Carlo d'Alessandro,
Director, IVD Quality and Regulatory
Donawa Lifescience Consulting Srl
Piazza Albania, 10 - 00153 Rome, Italy
Tel: +39 06 578 2665
Fax: +39 06 574 3786
cdalessandro@donawa.com |
| Device Trade Name: | STA® - Liatest® D-Di |
| Regulatory Information: | |
| Classification Name: | Fibrinogen and fibrin split products, antigen, antiserum, control |
| Regulatory Class: | Class II |
| Panel: | Hematology |
| Product Code: | DAP |
| Regulation Number: | 864.7320 |
| Predicate Device: | VIDAS® D-Dimer Exclusion™ (K040882) |
Device Intended Use:
✔ New Device Intended Use
The STA® - Liatest® D-Di kit is an immuno-turbidimetric assay for the quantitative determination of D-dimer in venous plasma (in 3.2% sodium citrate) for use on STA-R®, STA Compact® and STA Satellite® analyzers by professional laboratory personnel. The STA® - Liatest® D-Di is intended for use in conjunction with a clinical pretest probability (PTP) assessment model to exclude pulmonary embolism (PE) and deep venous thrombosis (DVT) in outpatients suspected of PE or DVT.
4
Image /page/4/Picture/0 description: The image shows the logo for Stago. The logo consists of the word "Stago" in a serif font, with the letters in a dark red color. Above the word "Stago" is an abstract graphic element. The graphic element is composed of two curved shapes, one in a dark red color and the other in a gray color, arranged in a circular fashion.
✓ Previous Device Intended Use
The STA® - Liatest® D-Di kit is an immuno-turbidimetric assay for the quantitative determination of D-dimer in venous plasma (in 3.2% sodium citrate) for use on STA-R®, STA Compact® and STA Satellite® analyzers by professional laboratory personnel. The STA® -Liatest® D-Di is intended for use in conjunction with a clinical pretest probability (PTP) assessment model to exclude pulmonary embolism (PE) and as an aid in the diagnosis of deep venous thrombosis (DVT) in outpatients suspected of PE or DVT.
Device description:
STA® - Liatest® D-Di kit contains: 6 x 5-ml vials of ready-for-use Tris buffer and 6 x 6-ml vials of a suspension of microlatex particles coated with two different mouse monoclonal anti-human D-dimer antibodies (8D2 and 2.1.16) stabilized with bovine albumin.
The test principle is based on the change in turbidity of a microparticle suspension that is measured by photometry. A suspension of latex microparticles, coated by covalent bonding with monoclonal antibodies specific for D-dimer is mixed with the test plasma for which the D-dimer level is to be assayed. An antigen-antibody reaction takes place, leading to an agglutination of the latex microparticles which causes an increase in turbidity of the reaction medium. This increase in turbidity is reflected by an increase in absorbance, the latter being measured photometrically. The increase in absorbance is a function of the D-dimer level present in the test sample.
Statement of technological characteristics of the device compared to predicate device:
The STA® - Liatest® D-Di kit and the Vidas® D-Dimer Exclusion™ (K040882) have different assay method and test principle. However, both kits are equivalent considering their intended use for excluding PE and DVT.
| Device | Predicate Device | |
|---|---|---|
| Attributes or | ||
| characteristics | Diagnostica Stago, | |
| STA® - Liatest® D-Di | bioMérieux, | |
| VIDAS® D-Dimer Exclusion™ | ||
| K040882 | ||
| Indications for | ||
| Use | Quantitative determination of D- | |
| dimer in venous plasma (in 3.2% | ||
| sodium citrate) for use on STA-R®, | ||
| STA Compact® and STA Satellite® | ||
| analyzers by professional laboratory | ||
| personnel. The STA® - Liatest® D-Di | ||
| is intended for use in conjunction | ||
| with a clinical pretest probability | ||
| (PTP) assessment model to exclude | ||
| pulmonary embolism (PE) and deep | ||
| venous thrombosis (DVT) in | ||
| outpatients suspected of PE or DVT. | Automated quantitative test for use | |
| on the VIDAS instruments for the | ||
| immunoenzymatic determination of | ||
| fibrin degradation products (FbDP) | ||
| in human plasma (sodium citrate) | ||
| using ELFA technique (Enzyme | ||
| Linked Fluorescent Assay). The | ||
| assay is indicated for use in | ||
| conjunction with a clinical pretest | ||
| probability assessment model to | ||
| exclude deep vein thrombosis (DVT) | ||
| and pulmonary embolism (PE) | ||
| disease in outpatients suspected of | ||
| PE or DVT. | ||
| Device | Predicate Device | |
| Attributes or | ||
| characteristics | Diagnostica Stago, | |
| STA® - Liatest® D-Di | bioMérieux, | |
| VIDAS® D-Dimer Exclusion™ | ||
| K040882 | ||
| Analyte(s) | ||
| measured | D-dimer | D-dimer |
| Cut-off | 0.5 µg/mL | 500 ng/mL (same) |
| Clinical | ||
| performances | For exclusion of PE on low and | |
| moderate PTP population (n = 1130): | ||
| Sensitivity = 97.0% (95% CI: 91.6% |
- 99.4%)
NPV = 99.7% (95% CI: 99.2% -
100.0%)
For exclusion of DVT on low and
moderate PTP population (n = 980):
Sensitivity: 100.0 % (95% CI: 95.8% - 100.0 %)
NPV: 100.0 % (95% CI: 99.3 % -
100.0 %) | For exclusion of PE on low and
moderate PTP population (n = 891):
Sensitivity: 100.0 % (95% CI: 97.7% - 100.0 %)
NPV: 100.0 % (95% CI: 98.7 % -
100.0 %)
For exclusion of DVT on low PTP
population (n = 295):
Sensitivity: 100.0 % (95% CI: 81.5% - 100.0 %)
NPV: 100.0 % (95% CI: 96.7 % -
100.0 %)
For exclusion of DVT on moderate
PTP population (n=189):
Sensitivity: 100.0 % (95% CI:
80.5% - 100.0 %)
NPV: 100.0 % (95% CI: 92.3 % -
100.0 %) |
| Anatomical Sites | Not applicable.
No direct patient contact. | Not applicable.
No direct patient contact. |
| Where Used:
Hospital, home,
ambulance, etc. | Hospital Laboratory or other Health
Care Laboratory. | Hospital Laboratory or other Health
Care Laboratory. |
| Sterility | No sterility requirements.
No direct patient contact. | No sterility requirements.
No direct patient contact. |
| Biocompatibility | No biocompatibility requirements.
No direct patient contact. | No biocompatibility requirements.
No direct patient contact. |
| Chemical Safety | No issues regarding chemical safety
due to no direct patient contact. | No issues regarding chemical safety
due to no direct patient contact. |
Similarities Chart with VIDAS® D-Dimer Exclusion™ (K040882)
5
Image /page/5/Picture/0 description: The image shows the logo for Stago. The logo features the word "Stago" in a serif font, with the "S" capitalized and the rest of the letters in lowercase. Above the word "Stago" is an abstract graphic element that resembles a stylized leaf or droplet shape. The top part of the shape is a reddish-brown color, while the bottom part is a muted gray-brown color.
Differences Chart with VIDAS® D-Dimer Exclusion™ (K040882)
| Attributes or
| characteristics | Device | Predicate Device |
|---|---|---|
| Contents of the | ||
| Kit | Diagnostica Stago, | |
| STA® - Liatest® D-Di | bioMérieux, | |
| VIDAS® D-Dimer Exclusion™ | ||
| K040882 | ||
| Two reagents. | ||
| 6 x 5-ml Vials of Reagent 1 (Buffer) | - DD2 Reagent Strips- ready to use |
- 2x30 DD2 Solid Phase Receptors |
6
Image /page/6/Picture/0 description: The image contains the logo for Stago. The logo features the word "Stago" in a red, serif font. Above the word is an abstract graphic element. The graphic element is composed of two shapes, one red and one gray, that appear to be interlocking or overlapping.
| Device | Predicate Device | |
|---|---|---|
| Attributes or | ||
| characteristics | Diagnostica Stago, | |
| STA® - Liatest® D-Di | bioMérieux, | |
| VIDAS® D-Dimer ExclusionTM | ||
| K040882 | ||
| 6 x 6-ml Vials of Reagent 2 (Latex) | (SPR) |
- 1 x 25-ml DD2 diluent Vial (liquid)
- 3 x 2-ml Vials of C1 and C2
control (lyophilized) - 2 x 2-ml Vials of S1 and S2
calibrator (lyophilized) |
| Assay Method | Immuno-turbidimetric method | ELFA technique (Enzyme Linked
Fluorescent Assay) |
| Test Principle | Immuno-turbidimetric method based
on the measurement of light
absorbance (at 540 nm) produced by
a suspension of microlatex particles
coated with specific mouse anti-
human D-dimer monoclonal
antibodies. | The assay combines a two-step
enzyme immunoassay sandwich
method with a final fluorescent
detection step (ELFA). |
| Analyzers | IVD analyzers of the STA® line. | VIDAS instruments |
Clinical Performance Data:
A clinical multi-center study (16 sites over the United States, Europe and Canada), conducted according to CLSI H59-A, was performed to demonstrate the ability of STA® - Liatest® D-Di to safely rule-out DVT by using samples of prospective, consecutive, ambulatory outpatients (presenting at the emergency unit or outpatient clinic) suspected of having venous thromboembolism (VTE).
The study population was recruited from prospective, ambulatory outpatients suspected of having DVT. After consenting, these patients were evaluated using the Wells score as pretest probability (PTP) model:
- -Patients with low or moderate PTP were considered for D-dimer testing:
- those with positive D-dimer result were considered for an imaging procedure ●
- those with negative D-dimer result were considered as not having DVT and . assigned to a three month follow up.
- Patients with high PTP were considered for an imaging procedure and not included in the study's primary analyses.
D-dimer assays were carried out using STA® - Liatest® D-Di on fresh plasma samples or on frozen plasma samples tested within 30 days of blood collection.
For primary efficacy analysis the population of interest was limited to patients with a PTP result low or moderate. In this group, only patients with a negative D-dimer result had a follow up call or visit at 3 months.
7
Image /page/7/Picture/0 description: The image shows the logo for Stago. The logo consists of the word "Stago" in a serif font, with the letters in a reddish-brown color. Above the word is an abstract graphic element, also in reddish-brown and gray. The graphic element appears to be composed of three curved shapes arranged in a circular fashion.
The study product was used in accordance with routine clinical practice and sites used imaging procedures according to standard of care.
Results:
980 samples of patients with a low or moderate PTP were included in the primary efficacy analyses (79 suspects of DVT and PE and 901 suspects of DVT only).
Of the 980 samples, 85 were from DVT positive and 895 from DVT negative patients.
The overall prevalence of DVT (low and moderate PTP patients with positive imaging) in the prospective study population was 8.4 % with 6.0 % in the US population and 9.8% in the European/Canadian ("out of US") population.
Primary efficacy analyses of the study included calculation of two co-primary parameters: Negative Predicted Value (NPV) and Sensitivity which were tested versus four (4) performance goals-two using 95 % two-sided confidence intervals (CI) and two versus point estimates.
All the efficacy parameters with upper and lower limit of 95 % confidence intervals (CI) were calculated in the overall study population, and separately for the US population and the "out of US" population with the STA® - Liatest® D-Di clinical cut-off of 0.50 µg/ml (FEU) in the (low + moderate) PTP group of patients.
Results obtained for each study population are detailed below:
Table 1 Results obtained on the overall prospective study population
| Overall | Reference (imaging or 3-month follow-up) | |||
|---|---|---|---|---|
| Positive | Negative | Total | ||
| D-dimer | Positive | 85 | 401 | 486 |
| Negative | 0 | 494 | 494 | |
| Total | 85 | 895 | 980 |
Sensitivity (95 % CI) = Specificity (95 % CI) = NPV (95 % CI) = PPV (95 % CI) =
100% (95.8% - 100%) 55.2% (51.9% - 58.5%) 100% (99.3% - 100%) 17.5% (14.2% - 21.2%)
Table 2 Results obtained on the US prospective study population
| Reference (imaging or 3-month follow-up) | ||||
|---|---|---|---|---|
| US | Positive | Negative | Total | |
| D-dimer | Positive | 22 | 145 | 167 |
| Negative | 0 | 202 | 202 | |
| Total | 22 | 347 | 369 |
Sensitivity (95 % CI) = Specificity (95 % CI) = NPV (95 % CI) = PPV (95 % CI) =
100% (84.6% - 100%) 58.2% (52.8% - 63.5%) 100% (98.2% - 100%) 13.2% (8.4% - 19.3%)
8
Image /page/8/Picture/0 description: The image shows the logo for Stago. The logo consists of the word "Stago" in a red, serif font. Above the word is an abstract design featuring two curved shapes, one red and one gray, arranged in a circular pattern. The red shape is larger and positioned above the gray shape.
| Out of US | Reference (imaging or 3-month follow-up) | |||
|---|---|---|---|---|
| Positive | Negative | Total | ||
| D-dimer | Positive | 63 | 256 | 319 |
| Negative | 0 | 292 | 292 | |
| Total | 63 | 548 | 611 |
Sensitivity (95 % CI) = Specificity (95 % CI) = NPV (95 % CI) = PPV (95 % CI) =
100% (94.3%-100%) 53.3% (49.0%-57.5%) 100% (98.7%-100%) 19.7% (15.5%-24.5%)
This study demonstrates that the STA® - Liatest® D-Di is effective in excluding deep venous thrombosis (DVT) in patient with a low or moderate PTP and a D-dimer level