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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Arthritis, Rheumatoid, Case-Control Studies, Cohort Studies, Humans, Latex Fixation Tests, Middle Aged, Nephelometry and Turbidimetry, Predictive Value of Tests, Rheumatoid Factor, Sensitivity and Specificity.
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Is in the era of nephelometry , latex agglutination still good enough to detect rheumatoid factor? Context: To compare quantitative nephelometry to the traditional semiquantitative latex agglutination (LAT) test for rheumatoid factor (RF). We evaluated 564 patients with rheumatoid arthritis (RA) and 155 controls using both techniques. The cutoff value of 40 IU/ml was established for a positive RF result. Sensitivity of LAT and nephelometry was 85.5% and 88.3%, respectively. Both techniques had a similar specificity and a positive predictive value exceeding 95%. Agreement (kappa = 0.86) and correlation (0.87) between the 2 methods were significant.
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In routine practice, and particularly in developing countries such as India, LAT can still be the preferred method for RF determination. Final Decision: yes