Table 2 Step 1 - Selecting pain-indicative facial descriptors that are (a) observed in more than half (> 50%) of the pain videos (5 kg) and (b) that can differentiate between no-pain (non-noxious 2 kg stimulatus) and pain (noxious 5 kg stimulus) (effect size > 0.80)
From: Using observational facial descriptors to infer pain in persons with and without dementia
|  | A. Frequency with which the facial descriptors were used; when judging facial expressions to 5 kg pain (in percentage (%)) | B. Ability of a facial descriptor to differentiate between facial expressions to 2 and 5 kg (effect size, Cohen’s d) | Selected for further analyses1 | ||||
|---|---|---|---|---|---|---|---|
| Â | All videos | Healthy elderly | Patients with dementia | All videos | Healthy elderly | Patients with dementia | Â |
Frowning | 80% | 81% | 79% | 4.61 | 2.56 | 3.38 | x |
Narrowing eyes | 61% | 56% | 66% | 4.79 | 2.33 | 4.61 | x |
Closing eyes | 26% | 18% | 34% | 2.29 | −1.25 | 4.50 |  |
Raising upper lip | 54% | 53% | 55% | 5.09 | 3.34 | 4.43 | x |
Opened mouth | 53% | 50% | 56% | 5.37 | 2.71 | 5.26 | x |
Tightened lips | 58% | 55% | 61% | 1.10 | 0.86 | 0.88 | x |
Empty gaze | 57% | 55% | 59% | −2.27 | −1.13 | −1.61 |  |
Seeming disinterested | 47% | 48% | 46% | −2.55 | −1.30 | −1.73 |  |
Teary eyes | 32% | 28% | 37% | 0.94 | 0.13 | 1.00 | Â |
Looking tense | 83% | 80% | 86% | 4.03 | 1.79 | 3.54 | x |
Looking sad | 76% | 72% | 81% | −0.28 | −0.93 | 0.33 |  |
Looking frightened | 70% | 65% | 74% | 2.86 | 1.38 | 2.09 | x |