Table 3

Categorised statements about blinding found in the methods section of analysed trials (N=470)

Categories of descriptorsn (%)
Double-blind191 (41)
Personnel blinded75 (16)
Single-blind38 (8.1)
Patients and personnel blinded37 (7.9)
Outcome assessor blinded26 (5.5)
Data collectors blinded19 (4.0)
Non-blinded personnel17 (3.6)
Patients blinded16 (3.4)
Blinded14 (3.0)
Open label8 (1.7)
Data analysts blinded8 (1.7)
Partially blinded3 (0.6)
Unmasked patients and investigators3 (0.6)
Non-blinded patients2 (0.4)
Blinded interventions2 (0.4)
Triple-blind1 (0.2)
Unmasking information1 (0.2)
Non-masked patients and personnel1 (0.2)
Rater blinded1 (0.2)
Masked assignment1 (0.2)
Masking1 (0.2)
Outcome assessors and data analysts blinded1 (0.2)
Data collector and data analysts blinded1 (0.2)
Data collector and outcome assessor blinded1 (0.2)