OBJECTIVE: To assess whether direct to healthcare professional communications (DHPCs) are of sufficient quality to be applicable in clinical practice and study how the quality differs according to safety concerns and type of monitoring.

DESIGN: Retrospective cohort study.

SETTING: DHPCs containing monitoring instructions were identified among all DHPC issued in Denmark between 2007 and 2018.

INTERVENTION: Quality of information of monitoring instructions was assessed according to the Systematic Information for Monitoring (SIM) score. Associations between different characteristics of instructions and the SIM score were compared with analysis of variance and the post hoc test Tukey's honestly significant difference if significant.

RESULTS: In total, 297 DHPCs were issued, of which 97 contained 134 monitoring instructions. For 95% of these DHPCs the European Medicines Agency was involved. The average SIM score was 2.6±1.6 (ranging 0-6) and only 47% were considered of sufficient quality (SIM score ≥3). In addition, even fewer (11%) instructions were considered a 'adequate instruction' which also reported about facts and risks. Differences between quality of information according to type of monitoring were observed, specifically between clinical monitoring (average SIM score 1.9) and biomarker monitoring (physical average SIM score 2.9, p=0.029 and laboratory average SIM score 3.4, p<0.0001).

CONCLUSIONS: Monitoring instructions were found not to be of sufficient quality to be applicable in clinical practice according to the SIM score. Our study concludes the need for further research and regulatory steps to ensure improve quality of information in safety communications.