Table 2.

Mean and standard deviation of BNSS items at baseline and follow-up

		Baseline		Follow-up
BNSS domains and items	N	Mean	SD	Mean	SD
Anhedonia
BNSS1	612	2.86	1.54	2.54	1.57
BNSS2	612	2.96	1.57	2.55	1.56
BNSS3	612	2.86	1.58	2.61	1.62
Asociality
BNSS5	612	3.28	1.57	2.88	1.60
BNSS6	612	3.01	1.59	2.76	1.58
Avolition
BNSS7	612	2.87	1.61	2.59	1.61
BNSS8	612	2.82	1.61	2.59	1.57
Blunted affect
BNSS9	612	2.71	1.67	2.61	1.59
BNSS10	612	2.64	1.77	2.53	1.66
BNSS11	612	2.69	1.79	2.54	1.65
Alogia
BNSS12	612	2.21	1.72	2.06	1.69
BNSS13	612	2.42	1.79	2.27	1.73

Abbreviations: BNSS, brief negative symptom scale; BNSS items: 1 = intensity of pleasure during activities; 2 = frequency of pleasurable activities; 3 = intensity of expected pleasure from future activities; 5 = asociality behavior; 6 = asociality internal experience; 7 = avolition behavior; 8 = avolition internal experience; 9 = facial expression; 10 = vocal expression; 11 = expressive gestures; 12 = quantity of speech; 13 = spontaneous elaboration.

Note: All item scores decreased significantly (Wilcoxon’s test, p < 0.001) from baseline.