Table 2.
Details of standardised quantitative sensory testing battery, tests and associated peripheral sensory channel
| Group no. | Description | Test (abbreviation) | Peripheral sensory channel |
|---|---|---|---|
| 1 | Thermal detection thresholds for the perception of cold, warm and paradoxical heat sensations | Cold detection threshold (CDT) | A-delta |
| Warm detection threshold (WDT) | C | ||
| Performed using a medoc pathway stimulator, ramped stimuli 1°C/s, baseline temperature 32 °C and a 9 cm² thermode | Paradoxical heat sensations (PHS) | C, A-delta | |
| Thermal sensory lumen (TSL) | C, A-delta | ||
| 2 | Thermal pain thresholds for cold and hot stimuli (as above) | Cold pain threshold (CPT) | C, A-delta |
| Heat pain threshold (HPT) | C, A-delta | ||
| 3 | Mechanical detection thresholds for touch and vibration | Mechanical detection threshold (MDT) | A-beta |
| Performed using a modified set of von Frey hairs (0.25–512 mN) with five ascending and five descending stimulus intensities and a 64 Hz tuning fork (8/8) | Vibration detection threshold (VDT) | A-beta | |
| 4 | Mechanical pain sensitivity, including thresholds for pinprick, stimulus–response functions for pinprick sensitivity, dynamic mechanical allodynia and pain summation to repetitive pinprick stimuli | Mechanical pain threshold (MPT) | C, A-delta |
| Mechanical pain sensitivity (MPS) | C, A-delta | ||
| Performed using a set of weighted pin-pricks that exert forces of 8, 16, 32, 64, 128, 256 and 512 mN | Dynamic mechanical allodynia (DMA) | C, A-delta | |
| Wind-up ratio (WUR) | C, A-delta | ||
| 5 | Pressure pain threshold | Pressure pain threshold (PPT) | C, A-delta |
| Performed using an algometer with a 1cm² probe area, where stimulus intensity is gradually increased at a ramp rate of 50 kPa.s | |||
| 6 | Cold pain threshold and tolerance | Cold pressor test | C, A-delta |
| Performed with a custom cold pressor which maintains water at 2 °C, participants submerge their dominant hand in the water stating “pain” for threshold and tolerance is measured as the point at which the hand is voluntarily removed | |||
| 7 | Pain modulation | Conditioned pain modulation (CPM)a | – |
| Performed using an algometer with a 1 cm²-probe area, where stimulus intensity is gradually increased at a ramp rate of 50 kPa/s and a cold pressor test (see 6.) |
Test order: Cold and warm thermal detection thresholds are acquired first followed by paradoxical heat sensations during thermal sensory lumen of alternating warm and cold stimuli (no. 1). Cold and heat thermal pain thresholds (no. 2) are then determined. Then follows; mechanical detection (no. 3), mechanical pain (no. 4), stimulus/response functions with dynamic mechanical allodynia (no. 4), wind-up ratio (no. 4), vibration (no. 3), pressure pain (no. 5), cold pressor test (no. 6) and lastly conditioned pain modulation (no. 7) is performed
Additional tests that are not part of the DFNS QST battery (i.e. no. 6 & 7) are given in italics
aThis is a measure of central pain processes not of the peripheral sensory channels; although these channels are involved in the initial detection of the relevant stimuli (see no. 4 and 5)