Table 1 Psychometric properties of odor interpretation and odor naming tasks in the schizophrenia sample (N=881)

Item difficulty (weighted % correct naming ± 95%CI)

Pineapple

21.71 ± 0.01

73.0 ± 1.7

Pleasant

81.7 ± 1.2

Petrol

38.67 ± 0.02

78.2 ± 1.3

Sweet

72.6 ± 1.1

Mint

76.35 ± 0.03

78.0 ± 1.2

Hot

69.5 ± 1.4

Rose

39.99 ± 0.02

80.2 ± 1.3

Technical

81.3 ± 1.1

Natural gas

16.61 ± 0.02

70.9 ± 1.6

Natural

75.1 ± 1.3

Licorice

54.48 ± 0.03

82.3 ± 1.3

Edible

80.4 ± 1.2

Dangerous

79.5 ± 1.1

Item discrimination, part-whole corrected [95%CI]

Pineapple

0.24 [0.18, 0.30]

0.21 [0.15,0.27]

Pleasant

0.46 [0.40,0.51]

Petrol

0.25 [0.19, 0.31]

0.25 [0.19,0.31]

Sweet

0.33 [0.27,0.39]

Mint

0.30 [0.24, 0.36]

0.27 [0.20,0.33]

Hot

0.18 [0.11, 0.24]

Rose

0.28 [0.21, 0.34]

0.18 [0.11,0.24]

Technical

0.58 [0.53, 0.62]

Natural gas

0.13 [0.07, 0.20]

0.16 [0.09,0.22]

Natural

0.45 [0.40,0.50]

Licorice

0.27 [0.20, 0.33]

0.20 [0.14,0.27]

Edible

0.52 [0.47,0.56]

Dangerous

0.52 [0.47,0.56]

Item discrimination, not part-whole corrected [95%CI]

Pineapple

0.41 [0.35, 0.46]

0.57 [0.52,0.61]

Pleasant

0.63 [0.59,0.67]

Petrol

0.50 [0.45, 0.54]

0.53 [0.48,0.58]

Sweet

0.52 [0.47,0.56]

Mint

0.60 [0.55, 0.64]

0.52 [0.47,0.57]

Hot

0.44 [0.38,0.49]

Rose

0.56 [0.51, 0.61]

0.45 [0.40,0.50]

Technical

0.72 [0.69,0.75]

Natural gas

0.33 [0.26, 0.39]

0.50 [0.45, 0.55]

Natural

0.64 [0.60,0.68]

Licorice

0.65 [0.62, 0.69]

0.48 [0.43,0.53]

Edible

0.68 [0.64,0.71]

Dangerous

0.66 [0.62,0.70]

Internal consistency (standardized Cronbach’s α, equals average split-half reliability)

0.50 [0.47, 0.54]

0.44 [0.40,0.48]

0.72 [0.71,0.74]