Table 1.
Characteristics of the subjects (derivation and validation sets)
| Derivation set (N = 145) | Validation set (N = 61) | |
|---|---|---|
| Mean age, y ± SD | 45.9 ± 17.4 | 48.7 ± 17.1 |
| Male, n (%) | 49 (33.8) | 25(41) |
| Final diagnosis, n (%)a | ||
| Peripheral disease | 47 (32) | 24 (39) |
| DHT+ BPPV | 12 (8.3) | 6 (10) |
| Mean age, y ± SD | 57.0 ± 17.6 | 54.7 ± 16.3 |
| Male | 6 (50)b | 1 (17)b |
| DHT− BPPV | 30 (20.7) | 14 (23) |
| Meniere’s disease | 3 (2.1) | 1 (1.6) |
| Vestibular neuritis | 2 (1.4) | 3 (4.9) |
| Psychogenic disorders | 56 (39) | 18 (30) |
| Depressive disorder | 24 (17) | 5 (8.2) |
| Somatoform disorder | 12 (8.3) | 1 (1.6) |
| Adjustment disorder | 6 (4.1) | 5 (8.2) |
| Panic disorder | 5 (3.4) | 2 (3.3) |
| Anxiety disorder | 3 (2.1) | 3 (4.9) |
| Hypochondriasis | 2 (1.4) | 1 (1.6) |
| Othersc | 4 (2.8) | 1 (1.6) |
| Central diseases | 8 (5.5) | 3 (4.9) |
| Migraine | 3 (2.1) | 1 (1.6) |
| Transient ischemic attack | 2 (3.3) | |
| Othersd | 5 (3.4) | |
| Others | 19 (13) | 9 (15) |
| Orthostatic hypotension | 5 (3.4) | 1 (1.6) |
| Combined sensory disorder | 3 (2.1) | 1 (1.6) |
| Arrhythmia | 2 (1.4) | |
| Anemia | 2 (1.4) | |
| Drug-induced | 2 (1.4) | |
| Cervical vertigo | 2 (1.4) | |
| Overwork | 2 (1.4) | 1 (1.6) |
| Otherse | 1 (0.7) | 6 (9.8) |
| Unknown diagnosis | 15 (10) | 8 (13) |
| Patients requiring consultation with specialists, n (%) | 56 (39) | 15 (25) |
Notes: The derivation set is a group used for development of the predictive model, and the validation set is a group used for validation of the model.
Percentage of patients in each set; the total exceeds 100% because a patient had multiple diseases;
percentage of DHT+ BPPV patients in each set;
“others” includes the following diseases (n): conversion disorder (1), paranoia (1), acute stress disorder (1), and factitious disorder (1) in the derivation set; phobia (1) in the validation set;
“others” includes the following diseases (n): cerebral infarction (1), acoustic neuroma (1), epilepsy (1), Adie’s syndrome (1), and alcoholic cerebellar ataxia (1) in the derivation set;
“others” includes the following diseases: vasovagal reflex (1) in the derivation set; vasovagal reflex (1), sleep apnea syndrome (1), sleep deprivation (1), cytomegalovirus infection (1), dehydration (1) and deconditioning (1) in the validation set.
Abbreviations: SD, standard deviation; BPPV, benign paroxysmal positional vertigo; DHT+, positive Dix–Hallpike test; DHT−, negative Dix–Hallpike test.