Table 4.
Diagnostic tests performed due to chronic cough in the previous three years
| Diagnostic test | All patients (N = 196) | RCC (N = 126) | UCC (N = 70) | p-value (RCC vs. UCC) | |
|---|---|---|---|---|---|
| a. Image | |||||
| Chest x-radiography | Number of patients (%) | 164 (83.7) | 108 (85.7) | 56 (80.0) | 0.300 |
| Mean (SD) tests per patient performed* | 2.1 (1.7) | 2.1 (1.8) | 2.0 (1.3) | 0.612 | |
| Mean (SD) tests per patient, all patients** | 1.8 (1.7) | 1.8 (1.9) | 1.6 (1.4) | 0.359 | |
| X-radiography of other locations | Number of patients (%) | 44 (22.4) | 31 (24.6) | 13 (18.6) | 0.332 |
| Mean (SD) tests per patient performed* | 2.0 (1.7) | 2.0 (1.9) | 2.2 (1.2) | 0.745 | |
| Mean (SD) tests per patient, all patients** | 0.5 (1.2) | 0.5 (1.3) | 0.4 (1.0) | 0.629 | |
| Chest CT scan | Number of patients (%) | 100 (51.0) | 69 (54.8) | 31 (44.3) | 0.160 |
| Mean (SD) tests per patient performed* | 1.3 (1.0) | 1.4 (1.2) | 1.2 (0.5) | 0.312 | |
| Mean (SD) tests per patient, all patients** | 0.7 (1.0) | 0.8 (1.1) | 0.5 (0.7) | 0.094 | |
| b. Lung function and other lung tests | |||||
| Simple spirometry | Number of patients (%) | 111 (56.6) | 78 (61.9) | 33 (47.1) | 0.046 |
| Mean (SD) tests per patient performed* | 1.9 (1.2) | 2.0 (1.4) | 1.4 (0.7) | 0.017 | |
| Mean (SD) tests per patient, all patients** | 1.1 (1.3) | 1.3 (1.5) | 0.7 (0.9) | 0.002 | |
| Spirometry with bronchodilation test | Number of patients (%) | 151 (77.0) | 97 (77.0) | 54 (77.1) | 0.980 |
| Mean (SD) tests per patient performed* | 1.4 (0.8) | 1.5 (1.0) | 1.2 (0.5) | 0.048 | |
| Mean (SD) tests per patient, all patients** | 1.1 (1.0) | 1.1 (1.1) | 0.9 (0.6) | 0.126 | |
| Methacholine test | Number of patients (%) | 57 (29.1) | 36 (28.6) | 21 (30.0) | 0.833 |
| Mean (SD) tests per patient performed* | 1.1 (0.2) | 1.1 (0.3) | 1.0 (0.0) | 0.180 | |
| Mean (SD) tests per patient, all patients** | 0.3 (0.5) | 0.3 (0.5) | 0.3 (0.5) | 0.898 | |
| Exhaled nitric oxide test (FeNO) | Number of patients (%) | 94 (48.0) | 63 (50.0) | 31 (44.3) | 0.443 |
| Mean (SD) tests per patient performed* | 1.6 (1.1) | 1.8 (1.2) | 1.3 (0.8) | 0.045 | |
| Mean (SD) tests per patient, all patients** | 0.8 (1.1) | 0.9 (1.2) | 0.6 (0.8) | 0.055 | |
| c. Other laboratory determinations | |||||
| Total IgE Determination | Number of patients (%) | 119 (60.7) | 87 (69.0) | 32 (45.7) | 0.001 |
| Mean (SD) tests per patient performed* | 1.4 (2.2) | 1.5 (2.5) | 1.1 (0.2) | 0.366 | |
| Mean (SD) tests per patient, all patients** | 0.8 (1.8) | 1.0 (2.2) | 0.5 (0.6) | 0.051 | |
| Determination of specific IgE against aeroallergens | Number of patients (%) | 78 (39.8) | 54 (42.9) | 24 (34.3) | 0.240 |
| Mean (SD) tests per patient performed* | 1.6 (2.5) | 1.3 (1.1) | 2.3 (4.2) | 0.116 | |
| Mean (SD) tests per patient, all patients** | 0.6 (1.8) | 0.6 (0.9) | 0.8 (2.7) | 0.395 | |
| Skin prick testing | Number of patients (%) | 103 (52.6) | 64 (50.8) | 39 (55.7) | 0.509 |
| Mean (SD) tests per patient performed* | 1.1 (0.4) | 1.1 (0.4) | 1.1 (0.2) | 0.234 | |
| Mean (SD) tests per patient, all patients** | 0.6 (0.6) | 0.6 (0.6) | 0.6 (0.6) | 0.945 | |
| d. Invasive diagnosis | |||||
| Rhinoscopy | Number of patients (%) | 66 (33.7) | 39 (31.0) | 27 (38.6) | 0.279 |
| Mean (SD) tests per patient performed* | 1.2 (0.5) | 1.3 (0.6) | 1.1 (0.3) | 0.209 | |
| Mean (SD) tests per patient, all patients** | 0.4 (0.7) | 0.4 (0.7) | 0.4 (0.6) | 0.746 | |
| Bronchoscopy | Number of patients (%) | 29 (14.8) | 19 (15.1) | 10 (14.3) | 0.881 |
| Mean (SD) tests per patient performed* | 1.0 (0.0) | 1.0 (0.0) | 1.0 (0.0) | (*) | |
| Mean (SD) tests per patient, all patients** | 0.1 (0.4) | 0.1 (0.4) | 0.1 (0.4) | 0.882 | |
| Laryngoscopy | Number of patients (%) | 41 (20.9) | 26 (20.6) | 15 (21.4) | 0.896 |
| Mean (SD) tests per patient performed* | 1.2 (0.8) | 1.3 (1.1) | 1.0 (0.0) | 0.266 | |
| Mean (SD) tests per patient, all patients** | 0.3 (0.6) | 0.3 (0.7) | 0.2 (0.4) | 0.549 | |
| Upper gastrointestinal endoscopy | Number of patients (%) | 54 (27.6) | 41 (32.5) | 13 (18.6) | 0.036 |
| Mean (SD) tests per patient performed* | 1.1 (0.4) | 1.1 (4.0) | 1.1 (0.3) | 0.708 | |
| Mean (SD) tests per patient, all patients** | 0.3 (0.5) | 0.4 (0.6) | 0.2 (0.4) | 0.038 | |
| Esophageal manometry/pH monitoring | Number of patients (%) | 46 (23.5) | 33 (26.2) | 13 (18.6) | 0.228 |
| Mean (SD) tests per patient performed* | 1.1 (0.5) | 1.2 (0.6) | 1.0 (0.0) | 0.290 | |
| Mean (SD) tests per patient, all patients** | 0.3 (0.5) | 0.3 (0.6) | 0.2 (0.4) | 0.083 | |
The table shows diagnostic tests performed on more than 25% of patients and invasive tests. See Supplementary Table 2 for information about additional tests, including other image and lung function tests and other laboratory and microbiological determinations. *Mean and SD were calculated on patients who had received the diagnostic test listed. **Mean number of tests per patient in the previous three years calculated with the overall population as the denominator, including patients who had not received such diagnostic test. (*) All patients underwent one bronchoscopy; the p-value cannot be calculated. CT computed tomography; RCC refractory chronic cough; SD standard deviation; UCC unexplained chronic cough