Analysis of the Spanish-speaking mailing list RADIOLOGIA.

The objective of this study was to analyse the mailing list RADIOLOGIA during its first 5 years of operation (from 1998 to 2003). A survey questionnaire was sent to evaluate the characteristics of subscribers and to score (from 0 to 9) the functionality, usefulness and quality of the mailing list. All messages sent to the list during the evaluated period were classified and quantified. A social network analysis was performed from all messages replied to during 2001 and 2002 with the option "reply to" included in the subject. One hundred and forty (36.8%) responses were collected from 380 subscribers, mainly radiologists (90.0%). 80% of responders were located in Spain, 16% in Latin America, and 4% in other places. The obtained scores (mean+/-standard deviation) were: functionality 7.4+/-1.3; usefulness 7.0+/-1.4; and quality of e-mail contents 6.0+/-1.4. During the evaluated period 2700 e-mail messages were sent to the list, with a monthly distribution of 44.3+/-26.0. The list functioning has been based on an active minority of subscribers that provided information and responses to the rest of the subscribers, a ring of active members that participated in discussions, and about 50% of passive members.