A-362 Analytical validation of a semi-automated portable IoT-enabled POCT device for screening of non-communicable diseases

Abstract

Mobilab Duo is a semi-automated, IoT-enabled, battery-operated, point-of-care testing (POCT) device designed in the form of a compact, portable suitcase (Figure 1) developed by Primary Health Tech Pvt. Ltd. in collaboration with IIT Guwahati, India, for screening of non-communicable diseases. This device is designed to operate in low-resource settings with features including offline functionality, app-based calibration, and user-level quality control (QC) testing. This study evaluates the analytical performance of Mobilab Duo using a validation protocol developed using CLSI EP09c and EP15-A3 guidelines, customised to suit for resource limited settings. Analytical validation was performed in the Department of Laboratory Medicine, AIIMS New Delhi. Fourteen analytes were evaluated: glucose, urea, creatinine, uric acid, total protein, albumin, total bilirubin (TBil), ALT, AST, total cholesterol, triglycerides, LDL, hemoglobin, and HbA1c. For accuracy testing, 30 patients per analyte were enrolled after obtaining institutional ethical clearance and informed consent. Paired samples were collected, and blinded testing was done on the same day and compared against fully automated analysers (Roche cobas c702/c502 and Sysmex XN-10). Mean modulus percentage bias was calculated. Method comparison was performed using Bland-Altman plots and Passing-Bablok regression. The percentage bias with 95% CI and limits of agreement (LoA) were calculated and evaluated against predefined tolerance limits. Precision (intra-day, inter-day, and inter-device) was evaluated using three devices in a 5×5×5 design with pooled serum and whole blood samples spanning 4 concentration ranges (very low to very high). CV % were calculated and evaluated against predefined limits. Linearity was evaluated using 10 serial dilutions across the analytical measurement range. Correlation analysis was done between expected and measured values. Overall performance of each analyte was analysed individually as per its intended use and based on predefined tolerance limits. Proportion of non-agreeable results and percentage of over- vs under-estimation were calculated. Strong correlation with reference analyzers was observed for all analytes (R² = 0.95). Ten out of fourteen analytes demonstrated acceptable accuracy (mean modulus bias <15%). Higher bias was observed for creatinine (19.4%), TBil (25.7%), ALT (18.5%) and AST (26.4%). Overall CV% was observed to be <10% for all analytes except creatinine, TBil, ALT (at very low and low ranges) and AST (at very low range). Bland-Altman plots were generated and LoA were evaluated against tolerance limits. Linearity was excellent across all parameters (R² = 0.985–0.9999) Mobilab Duo demonstrated acceptable analytical performance, reproducibility, and method comparability with standard laboratory analyzers for most routine parameters. Although analytical bias was observed to be beyond acceptable limits for creatinine, ALT and AST, precision data revealed that this arose due to high degree of imprecision of these parameters at very low /low levels. However, since this device is intended to be used at the point of care for screening purposes, the very low and low ranges would not materially impact screening-level clinical decision making. Summarily, Mobilab Duo shows substantial potential as a scalable POCT solution for community and primary care diagnostics in resource-limited settings for screening of non-communicable diseases.