Critical assessment of high-circulation print newspaper coverage of the Institute of Medicine report Dietary Reference Intakes for Calcium and Vitamin D.

Abstract

To evaluate high-circulation US and Canadian newspaper coverage of the Institute of Medicine (IOM) report Dietary Reference Intakes for Calcium and Vitamin D and assess pre-report and post-report reporter-specific vitamin D-related coverage. Two independent reviewers analysed the newspaper articles. The key report findings cited, proportion of sentences describing the IOM report and proportion of sentences describing critical viewpoints on the report were calculated. The content of articles written by reporters with a history of pre-report vitamin D-related articles was compared with that of articles written by reporters without such a history. Factiva and LexisNexis searches of the top thirty US and three English-language Canadian print newspapers, by circulation. Articles on the IOM report published from 30 November to 21 December 2010 and previous vitamin D-related articles written by the same reporters. Only ten articles met inclusion/exclusion criteria. Articles inconsistently cited the key findings in the IOM report. Reporters with a history of pre-report articles highlighting the benefits of vitamin D dedicated a greater proportion of sentences to viewpoints critical of the IOM report (P < 0·01). There was no significant difference between pre-report publication history and proportion of sentences focused on the IOM report. A borderline-significant difference (P = 0·058) was observed between pre-report articles highlighting the benefits of vitamin D and the absence of reference to potential risks of vitamin D overconsumption. Our findings suggest that newspaper articles did not consistently or comprehensively report the IOM recommendations and that pre-report publication history of reporters was related to post-report article content.