Communicating safety information to physicians: an examination of dear doctor letters.

Purpose: Recent research suggests that letters to healthcare providers may not effectively communicate safety-related information. This study examined whether content, organization, and formatting of dear doctor letters (DDLs) influences physicians' responses to the letters.

Methods: Drugs with warning label changes during 2000 and 2001 were identified, and corresponding DDLs were obtained. Letters were coded for content, organization, and formatting. Ten physicians rated letters on presentation, criticalness of the information, and likelihood of changing practice as a result of the letter. Areas of deficiency were identified. The relationships between key characteristics of the letters and physicians' ratings were examined using correlations; reliability of physicians' ratings was estimated using generalizability theory.

Results: For 2000 and 2001, 124 drugs were identified as having had changes to the warning section of the label; DDLs were sent in 32 (25.8%) instances. Letters varied in terms of the placement of key information, use of formatting, and length. Physicians' ratings suggested 25% of the letters were deficient in clarity, 28% in readability, 36% in the ratio of relevant information to supporting information, 36% in key information easily discernable, and 28% in overall effectiveness of communication. Letters with formatting highlighting key information were preferred. Letter length and placement of key information were not correlated with physicians' ratings.

Conclusions: Many DDLs do not communicate labeling changes clearly and effectively. If DDLs are used to communicate safety information to physicians, special formatting and explicit wording should be used to emphasize new information.