| First author [ref.] | Country | Agent | Study design | Duration of FU months | Symptom recovery n/N | Recovery of NSBHR n/N |
| Brant [34] | UK | Enzymes | Workforce-based survey of 35 out of 45 cases | 37 (4–39) | 5/35 | NA |
| Klusackova [35] | Czech Republic | Various | Longitudinal FU of 37 cases (selection not stated) Clinic-based study | 78 (12–216) | 5/37 | 1/19 |
| Labrecque [36] | Canada | Isocyanates | Retrospective cohort study of compensated subjects (89 randomly selected subjects) | ∼24 for all subjects | 4/79¶ | 10/79 |
| Park [38] | Korea | Reactive dyes | Longitudinal FU of 26 cases (selection not stated) Clinic-based study | Second visit: 104±22 (n=19) | NA | 11/16 |
| Park [37] | Korea | Reactive dyes | Longitudinal FU of 11 cases (selection not stated) Clinic-based study | 164±28 | 0/11 | 3/11 |
| Pisati [39] | Italy | Isocyanates | Longitudinal FU of 53 cases (selection of 25 patients rechallenged with TDI) Clinic-based study | 58±7 (46–73) | 10/25 | 12/25 |
| Yacoub [40] | Canada | Various | Retrospective cohort study of 40 compensated subjects | 44±34 | 6/40 | 10/40 |
| Munoz [41] | Spain | Persulfate salts | Prospective longitudinal FU of 10 out of 11 cases Clinic-based study | 63±19 (39–101) | 2/7 | 5/7 |
| Pooled estimates# | 32/234, 15.5%¶ (8.3–27.1%) | 52/197, 32.8% (16.8–54.3%) |
Data for individual studies are presented as mean (range), mean±sd or mean±sd (range), unless otherwise stated. Pooled estimates are presented as n/N with % (95% CI). FU: follow-up; NSBHR: nonspecific bronchial hyperresponsiveness; NA: not available; TDI: toluene diisocyanate. #: pooled estimates based on a random-effect model; ¶: the rate of symptom recovery was 19.2% (28 out of 155 subjects; 95% CI 11.2–30.9%) after exclusion of the study by Labrecque et al. [36], which used more stringent criteria of “clinical remission” defined by the absence of symptoms, NSBHR and medication.