Model-based methods and apparatus for classifying an interferent in specimens

A testing apparatus adapted to determine a characteristic of a specimen in a sample container, comprising:

• one or more image capture devices configured to capture one or more images of the specimen and at least a portion of the sample container and at least a portion of a label affixed to the sample container, if present, from which a pixelated image is generated;
• a liquid/non-liquid detector, based upon a liquid classification model, operable to classify the pixels in the pixelated image as being either liquid or non-liquid and define one or more liquid regions;
• a pixel classifier, based on a multi-class classification model, operable to determine for the pixels in the liquid region a classification as normal, hemolysis, icterus, or lipemia;
• and
• an interferent type detector operable to detect, based on a result of the pixel classifier, one or more interferent type within the one or more liquid regions.

A method of determining a characteristic of a specimen contained within a sample container, comprising:

• generating a pixelated image of the specimen in the sample container at a quality control station in a first color space;
• converting the pixelated image from the first color space to a second color space;
• determining color components for pixels in the pixelated image in the second color space;
• classifying of the pixels in the pixelated image as being liquid or non-liquid based upon a liquid classification model;
• defining one or more liquid regions based upon pixels that are classified as liquid pixels;
• classifying the liquid pixels as being one of normal, hemolysis, icterus or lipemia based upon a multi-class classification model;
• determining that the one or more liquid regions is either normal or includes one or more types of interferent based upon a number of the liquid pixels in each of normal, hemolysis, icterus or lipemia;
• and
• determining an interferent level for at least some of the one or more types of interferent based upon a regression model.

A testing apparatus adapted to determine a characteristic of a specimen in a sample container, comprising:

• a plurality of image capture devices arranged around the specimen and configured to capture multiple images of the specimen and at least a portion of the sample container and at least a portion of a label affixed to the sample container, if present, from multiple viewpoints, from which a pixelated image is generated;
• a liquid/non-liquid detector, based upon a liquid classification model, operable to classify pixels in the pixelated image as being either liquid or non-liquid and define one or more liquid regions;
• a pixel classifier, based on a multi-class classification model, operable to determine for the pixels in the liquid region a classification as normal, hemolysis, icterus, or lipemia;
• and
• an interferent type detector operable to detect, based on a result of the pixel classifier, one or more interferent type within the one or more liquid regions.