(243 days)
The Mission® U120 Ultra Urine Analyzer is intended for use in conjunction with the Mission® Urinalysis Reagent Strips for the semi-quantitative detection of the following analytes in urine: Glucose, Bilirubin, Ketone (Acetoacetic Acid), Specific Gravity, pH, Blood, Protein, Urobilinogen, Leukocytes and Ascorbic Acid as well as the qualitative detection of Nitrite.
The instrument is intended for point-of-care, in vitro diagnostic use only. The measurement can be used in general evaluation of health, and aids in the diagnosis and monitoring of metabolic or systemic diseases that affect kidney function, endocrine disorders and diseases or disorders of the urinary tract. It is intended for professional use only.
The Mission® Liquid Urine Controls Liquid Diptube Urine Controls are assayed urine controls, intended for use in validating the precision of analyzer reading of urinalysis for one or more of the following analytes: Ascorbic acid, Glucose, Bilirubin, Ketone (Acetoacetic acid), Specific Gravity, Blood, pH, Protein, Urobilinogen, Nitrite and Leukocytes. It is intended for professional in vitro diagnostic use only.
The Mission® U120 Ultra Urine Analyzer is a reflectance photometer that analyzes the intensity and color of light reflected from the reagent areas of a urinalysis reagent strip. Without a urine analyzer, users must visually compare the reagent areas of the strip to a color chart using the naked eye. Mission® U120 Ultra Urine Analyzer also features data management and report generation capabilities.
Acceptance Criteria and Device Performance Study for Mission® U120 Ultra Urine Analyzer
This report summarizes the acceptance criteria and the study proving the device meets these criteria for the Mission® U120 Ultra Urine Analyzer, as derived from the provided 510(k) summary (K142543).
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for the Mission® U120 Ultra Urine Analyzer were established through comparison with a predicate device (ACON U120 Urine Analyzer, K070929) and through various performance studies, including sensitivity, precision, interference, and environmental stability. The primary acceptance criteria for clinical performance were based on the agreement levels with the predicate device.
| Test / Analyte | Acceptance Criteria (Implied) | Reported Device Performance (Exact / Within One Level Agreement with Predicate) |
|---|---|---|
| Clinical Study | High agreement with predicate device (ACON U120 Urine Analyzer) | |
| Leukocyte | N/A (implied high agreement) | 95.3% / 100% |
| Nitrite | N/A (implied high agreement) | 100% / 100% |
| Urobilinogen (Uro) | N/A (implied high agreement) | 93.4% / 100% |
| Protein (Pro) | N/A (implied high agreement) | 92.7% / 100% |
| pH | N/A (implied high agreement) | 86.8% / 100% |
| Blood (Blo) | N/A (implied high agreement) | 93.8% / 100% |
| Specific Gravity (SG) | N/A (implied high agreement) | 85.5% / 100% |
| Ketone | N/A (implied high agreement) | 96.4% / 100% |
| Bilirubin (Bil) | N/A (implied high agreement) | 97.4% / 100% |
| Glucose (Glu) | N/A (implied high agreement) | 95.7% / 100% |
| Ascorbic Acid (ASC) | N/A (implied high agreement) | 90.0% / 100% |
| Precision Study | 100% within +/- one block agreement (across all levels) | 100% within +/- one block agreement for all analytes and levels |
| >90% exact agreement (across all levels, where applicable) | Range from 92.2% to 100% exact agreement | |
| Sensitivity Study | Specific low and high end sensitivity ranges for each analyte | Met the defined low and high end sensitivity ranges (details in source) |
| Interference Study | Identification and characterization of interfering substances | Identified and characterized specific interfering substances and their effects |
| Temperature Flex Study | Operates satisfactorily within 2°C to 45°C | Validated operation within 2°C to 45°C |
| Humidity Flex Study | Strips remain stable for defined periods at various humidities | Established stability periods at 80% humidity levels |
| Voltage Flex Study | Operates properly within 86V to 264V | Confirmed proper operation between 86V and 264V |
| pH Flex Study | Characterization of pH effects on test results | Determined pH ranges for unaffected results and identified pH-related interferences |
Note: The exact acceptance criteria were not explicitly stated as numerical thresholds for each analyte in the provided document beyond the general statement of "demonstrated that the intended user can follow the product instruction and obtain comparable instrument read results when using the Mission®U120 Ultra Urine Analyzer and a predicate Analyzer." The reported performance statistics (exact and within one level agreement) implicitly serve as the achieved acceptance. For Sensitivity, the achievement of specific low and high end ranges, as listed in the document, constitutes the acceptance. For Precision, 100% within +/- one block agreement was explicitly stated.
2. Sample Size Used for the Test Set and Data Provenance
The primary clinical test set involved approximately 468 patient urine specimens for each analyte (sample sizes varied slightly for some analytes, e.g., 451 for Nitrite, 450 for Bilirubin, etc.). This number includes both patient-collected specimens and "few contrived urine specimens" to ensure coverage of the measuring range.
The data provenance is prospective, as it involved "patient urine specimens randomly collected from patients at each of 3 clinical sites" and "Additional study was carried out at 2 sites in US," indicating a planned data collection process for the study. The country of origin for the clinical data is the United States (2 sites in US mentioned).
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The ground truth for the clinical test set was established by comparing the results from the Mission® U120 Ultra Urine Analyzer with those from a predicate device, the ACON U120 Urine Analyzer (K070929), rather than human experts.
The testing was performed by 9 intended users in total across 3 clinical sites (3 users at each site). Their qualifications are described as "intended users," implying they are professionals who would typically operate such devices in a point-of-care setting, but specific expert qualifications (e.g., radiologist with 10 years of experience) are not provided.
4. Adjudication Method for the Test Set
The adjudication method used seems to be a direct comparison between the results obtained from the candidate device (Mission® U120 Ultra Urine Analyzer) and the predicate device (ACON U120 Urine Analyzer). The agreement percentages (exact and within one level) are reported, indicating that the predicate device's readings served as the reference for comparison. There is no mention of an independent adjudication panel or a consensus method among multiple experts for the test set's ground truth beyond the comparison to the predicate.
5. Multi Reader Multi Case (MRMC) Comparative Effectiveness Study
An MRMC comparative effectiveness study, in the traditional sense of evaluating human reader performance with and without AI assistance, was not performed. The study compared the new automated analyzer (Mission® U120 Ultra Urine Analyzer) against a predicate automated analyzer (ACON U120 Urine Analyzer), with "intended users" operating the devices. The study objective was to evaluate the performance of the new analyzer compared to the predicate and to observe operational issues. It did not focus on the effect size of how much human readers improve with AI vs. without AI assistance, as the "AI" (automated analyzer) is the primary testing modality being evaluated for its standalone performance relative to a predicate.
6. Standalone (i.e. algorithm only without human-in-the-loop performance) Study
Yes, a standalone study was performed. The core of the clinical study involved comparing the "Mission® U120 Ultra Urine Analyzer" reading "Mission® Urinalysis Reagent Strips" against the "ACON U120 Urine Analyzer" reading "Mission® Urinalysis Reagent Strips." This evaluates the algorithm-driven output of the Mission® U120 Ultra Urine Analyzer as a standalone device against a legally marketed predicate device. The precision, sensitivity, interference, and environmental studies also evaluate the device's performance in a standalone capacity under various conditions.
7. The Type of Ground Truth Used
For the clinical study, the reference standard (ground truth) was the performance of the legally marketed predicate device, the ACON U120 Urine Analyzer (K070929), when reading the same Mission® Urinalysis Reagent Strips. The study directly compared the results from the new device against those of the predicate. Some "contrived urine specimens" were also used, implying that these had pre-defined or known concentrations of analytes, which would also serve as a form of ground truth.
For the precision study, the "target concentration of the analyte in each control solution was confirmed with Siemens reagent strips read by Clinitek Status urine analyzer and Mission® Urinalysis Reagent Strip read by ACON U120 urine analyzer," indicating a combination of predicate devices and validated controls as ground truth.
For the sensitivity study, the "low and high end range of sensitivity" for the reagent strips were determined, which likely relied on precisely prepared samples with known analyte concentrations as the ground truth.
8. The Sample Size for the Training Set
The document does not explicitly state a separate "training set" sample size for the Mission® U120 Ultra Urine Analyzer, as it is primarily a reflectance photometer analyzing color changes rather than a complex machine learning model that typically requires a distinct training phase. The device's operation is based on pre-programmed algorithms for color interpretation.
The clinical study and other performance studies described serve as validation of the device's accuracy and functionality. If any internal calibration or parameter tuning occurred, the data used for that is not detailed in this section.
9. How the Ground Truth for the Training Set Was Established
As mentioned above, the document does not describe a distinct training set for a machine learning algorithm. The device is an optical reader with established "tests principles" based on reflectance photometry and CMOS image sensing. The "ground truth" for its development and programming would implicitly derive from the chemical reactions on the reagent strips and the expected colorimetric responses at different analyte concentrations. These foundational principles are well-established in urinalysis technology. The sensitivity study, for instance, establishes the "low and high end range of sensitivity" for the device, which reflects its ability to correctly interpret known concentrations.
§ 862.2900 Automated urinalysis system.
(a)
Identification. An automated urinalysis system is a device intended to measure certain of the physical properties and chemical constituents of urine by procedures that duplicate manual urinalysis systems. This device is used in conjunction with certain materials to measure a variety of urinary analytes.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 862.9.