AG2. Note that at least two fears are required. This is a change from the earlier version of CIDI, where only one fear was required. Wittchen and his colleagues showed that requiring at least two fears substantially improves the validity of the CIDI assessment of agoraphobia.

AG4a-4h These questions were developed by Uli Wittchen. Wittchen found in his German surveys that a number of respondents exclusively endorse a fear of being mugged or other real danger (AG4b). These people are seldom classified in blind clinical assessments as having agoraphobia.

AG9, AG11 These question series are divided into two because the DSM-IV and ICD-10 criteria for number and type of psycho-physiological symptoms differ somewhat. A reader referring to both sets of criteria will quickly pick up the logic of split and of the skip rules.

AG15. This is an example of the many new dimensional questions that have been added to the CIDI for NCS-R in order to help refine our classification of severity thresholds.

AG16. Although this question was designed based on pilot work to be an improvement on the original CIDI question, the NCS-R clinical reappraisal study shows that it failed. Indeed, as with social phobia, the validity of the agoraphobia assessment in NCS-R compared to blind SCID clinical re-interviews is better when we ignore responses to this question.

AG18. As with the specific phobia and social phobia sections, this question was added as a "second chance" assessment of recency based on evidence in pilot studies that respondents often confuse the basic recency question regarding the recency of being afraid of such situation and the recency of actually encountering a phobic situation that led to a panic attack. We found, consistent with the pilot work, that quite a few respondents who reported in AG17a recency of more than a year ago said that they would be very severely fearful if they were exposed to the phobic stimulus today, indicating that they still have the phobia.

AG19. This question was added for a similar reason as AG18. Again, many respondents who reported in AG17a that they no longer had the fear reported in AG19 that they all or most of the time avoided social situations.