Table 2.
Design characteristics that may be associated with blinding, compared by BI values and scenarios.
| Study characteristics | Number of studies | BI (V) | BI (S) | BI (|V| − |S|) |
Blinding scenario |
|---|---|---|---|---|---|
| Sample size | |||||
| N < 100 | 43 | 0.44 | −0.19 | 0.25 | Unblinded/random |
| N ≥ 100 | 11 | 0.28 | −0.20 | 0.08 | Unblinded/opposite |
| Blinding assessed | |||||
| Immediately | 19 | 0.50 | −0.19 | 0.31 | Unblinded/random |
| Later | 35 | 0.29 | −0.20 | 0.09 | Unblinded/opposite |
| Blinded parties | |||||
| Subjects | 22 | 0.52 | −0.27 | 0.25 | Unblinded/opposite |
| Subjects + research staff | 32 | 0.26 | −0.17 | 0.09 | Unblinded/random |
| Assessed for sensation of | |||||
| Deqi | 22 | 0.33 | −0.21 | 0.12 | Unblinded/opposite |
| Puncture | 32 | 0.35 | −0.19 | 0.16 | Unblinded/random |
| Subject's status | |||||
| Healthy | 12 | 0.43 | −0.06 | 0.37 | Unblinded/random |
| Symptomatic | 42 | 0.33 | −0.22 | 0.11 | Unblinded/opposite |
| Subject's acupuncture experience | |||||
| Naïve | 24 | 0.27 | −0.13 | 0.14 | Unblinded/random |
| Experienced | 19 | 0.32 | −0.19 | 0.13 | Unblinded/random |
| Sham device used | |||||
| Commercial | 22 | 0.47 | −0.32 | 0.15 | Unblinded/opposite |
| Custom | 14 | 0.48 | −0.17 | 0.31 | Unblinded/random |
| Penetrating | 12 | 0.16 | −0.08 | 0.08 | random/random |
| Toothpick or cocktail stick | 6 | 0.55 | −0.33 | 0.22 | Unblinded/opposite |
*Raw data available in Table 4.