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Surveillance System Assessing the Need for Updating Systematic Reviews

Date and Location




Friday 20 September 2013 - 15:30 - 17:00


Presenting author and contact person

Presenting author

Nadera Ahmadzai

Contact person

Nadera Ahmadzai
Abstract text
Background: Systematic reviews (SRs) go out of date as new evidence emerges. Instead of fixed periodic updating, an efficient SR currency surveillance program could be less resource intensive. Objectives: Based on methods we developed previously, three Evidence-based Practice Centers were tasked to establish and execute a surveillance program to identify the need for updating a cohort of Comparative Effectiveness Reviews (CERs) commissioned by the Agency for Healthcare Research and Quality. Methods: We incorporated two existing methods of updating signal detection into a step-by-step surveillance approach and assessed the currency of 24 CERs. New evidence was identified from: a) literature searches, b) expert opinion, and c) safety alerts. We determined the currency of conclusions in the reviews, and, based on their potential impact on decision-making, the updating priority (low, medium, or high) of CERs. Low or medium priority CERs were reassessed every six months (Figure 1). We did not update the reviews. Results: The CERs mainly compared effectiveness and safety of pharmaceuticals and surgical procedures for various health conditions (Table 1). The median number of studies in the original SRs was 104 (range, 8 to 436), new studies were 15 (range, 0 to 35), and the expert response rate was 35% (71% for re-assessed CERs). Of the nine identified safety alerts only one influenced the updating priority of one CER. Of the 24 CERs, two were classified as high (8%), five as medium (21%), and 17 as low (71%) priority for updating from 11 to 62 months after their last search date. Of the ten re-assessed CERs reassessed after six months, updating priority changed for only one CER. Conclusions: We established a surveillance program and evaluated 24 CERs. The application of the program is practical and efficient for assessing the need for updating SRs across a wide range of health interventions.