Table 3.
The prevalence of metal allergies in cases (n = 356) from the patch-test database, stratified by the number of revisions
| Cases operated once (n = 273) % (n) | Cases revised once (n = 70) % (n) | Cases revised two or three times (n = 13) % (n) | OR (95% CI) a | p-value a | |
|---|---|---|---|---|---|
| Metal allergy b | 16 (43) | 11 (8) | 0 | 1.38 (0.68–2.80) | 0.4 |
| Nickel allergy | 11 (29) | 10 (7) | 0 | 1.06 (0.48–2.32) | 0.9 |
| Cobalt allergy | 5.5 (15) | 5.7 (4) | 0 | 0.96 (0.32–2.81) | 1.0 |
| Chromium allergy | 2.9 (8) | 4.3 (3) | 0 | 0.68 (0.18–2.51) | 0.7 |
a Comparison of cases without revision and those with one revision (Chi-squared test). Fisher's exact test was used when the expected frequency in one of the cells was lower than 5.
b Metal allergy was defined as a positive patch-test reaction to nickel, cobalt, or chromium.
OR: odds ratio.
CI: confidence interval.