Table 1

 Patients’ characteristics at baseline

CharacteristicsParacetamol (n = 405)Placebo (n = 374)All (n = 779)
*SD, standard deviation; †duration of the disease is the interval between the first symptom probably due to knee OA and the selection visit; ‡MTF, medial tibiofemoral compartment; LTF, lateral tibiofemoral compartment; PF, patellofemoral compartment—data are presented as number (percentage).
Female, No (%)292 (72)291 (78)583 (75)
Age (years), mean (SD)*69 (12)70 (11)70 (11)
Body mass index (BMI), mean (SD)29 (5)29 (5)29 (5)
Disease duration (months),† mean (SD)46 (45)45 (48)46 (47)
Kellgren and Lawrence radiological score‡
    • 2⩽MTF<4 and LTF<4 and PF<4266 (66)243 (65)509 (65)
    • MTF⩾2 and LTF<2 and PF<298 (24)97 (26)195 (25)
    • 2⩽MTF<4 and LTF<2 and PF<290 (22)88 (24)178 (23)
    • LTF⩾2 and MTF<2 and PF<217 (4)13 (3)30 (4)
    • PF⩾2 and MTF<2 and LTF<228 (7)14 (4)42 (5)
Clinical symptoms at baseline
    Sudden increase of pain within the 2 weeks before D0, No (%)269 (66)240 (64)509 (65)
    Pain at night, No (%)214 (53)212 (57)426 (55)
    Morning stiffness (>20 minutes), No (%)342 (84)307 (82)649 (83)
    Knee effusion (at least moderate), No (%)34 (8)34 (9)68 (9)
    Global pain intensity mm, mean (SD)66.7 (18)69.0 (17)67.8 (18)
    Patient’s global assessment of knee OA (0–100 mm), mean (SD)66.0 (17)66.7 (18)66.4 (18)
    WOMAC Function subscale (0–100), mean (SD)54 (1554 (1554 (15
Prior OA treatments, No (%)
    NSAIDs only12 (3)11 (3)23 (3)
    Paracetamol only36 (9)36 (10)72 (9)
    Both10 (2)4 (1)14 (2)
    None347 (86)323 (86)670 (86)