Comparison of different methods and times for reading the tuberculin skin test
Bibliographic record
Abstract
BACKGROUND: Current guidelines vary on the recommended method and time for measuring tuberculin skin test (TST) indurations. OBJECTIVE: To evaluate the best time and method for assessing TST results and which purified protein derivative (PPD) to administer. DESIGN: Standard PPD (PPD-S) and PPD-RT23 were applied concurrently on each forearm in random order in 78 nurses. MEASUREMENTS: TST induration was measured at 48, 72 and 96 h by two nurses by palpation and a ruler, palpation and a Vernier caliper, ballpoint pen and a ruler or ballpoint pen and a Vernier caliper. TST differences were assessed using mixed-effects analysis. We also assessed the rate of false-positive/-negative results and the variability of the TST measurements. RESULTS: We performed 767 TST measurements. The adjusted mean TST size was larger with PPD-S than with PPD-RT23 (12.8 vs. 10.8 mm, P < 0.001), and at 72 h than at 48 h and 96 h (13.4 vs. 11.8 vs. 10.1 mm, P < 0.05). The smallest number of false results was observed with PPD-S, the ballpoint pen-ruler and at 72 h; palpation+ruler had the least variability at 72 h. CONCLUSIONS: The TST should ideally be performed with PPD-S and measured at 72 h with the ballpoint pen+ruler or palpation+ruler methods.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".