The 110-item version of DELTA9 should be used instead of the 120-item version because the 10 items of Social Anhedonia are excluded from the inventory. The syntax files for the 120-item version are provided for users who wish to calculate DELTA9 scores based on previous versions of the scale, i.e. the 10 Social anhedonia items are part of the instrument, but are not taken into account when calculating the total score.