Reliability and Comparison of Tuberculin Skin Test


Yedikule Education and Research Hospital for Chest Diseases and Thoracic Surgery, ISTANBUL - TURKEY


Background: To search the reliability of palpation technique in measuring tuberculin skin test and to compare the palpation technique with the ballpoint-pen technique. Materials and Methods: Setting: A dormitory for high school students. Participants: A total of 230 students were analyzed in this study; all of them were male and their ages ranged between 16 to 18 years. Measurements: All students were tested using 0.1 ml of purified protein derivative (PPD) containing 5TU (tuberculin unit) via the Mantoux method. Readings of tuberculin skin tests were done 72 hours later. Three readers measured the tuberculin skin test by palpation technique and another read it by ballpoint-pen technique, for each student. Results: With the palpation technique, Confidence Interval (CI) was 95% (0.56-0.76), and kappa coefficient was 0.62. According to these results, there was good reliability between the three observers who made the measurements by palpation technique. Between the measurements that were made by palpation and ballpoint-pen technique, interclass correlation coefficients were found 0.94, and there was good correlation between the two techniques. Conclusion: We conclude that when the two methods were performed by experienced observers, the reliability of results were similar. (Tanaffos 2003; 2(8): 49-53)