How frequently should "living" guidelines be updated? Insights from the Australian Living Stroke Guidelines

"Living guidelines" are guidelines which are continually kept up to date as new evidence emerges. Living guideline methods are evolving. The aim of this study was to determine how frequently searches for new evidence should be undertaken for the Australian Living Stroke Guidelines.

Members of the Living Stroke Guidelines Development Group were invited to complete an online survey. Participants nominated one or more recommendation topics from the Living Stroke Guidelines with which they had been involved and answered questions about that topic, assessing whether it met criteria for living evidence synthesis, and how frequently searches for new evidence should be undertaken and why. For each topic we also determined how many studies had been assessed and included, and whether recommendations had been changed.

Fifty-seven assessments were received from 33 respondents, covering half of the 88 guideline topic areas. Nearly all assessments (49, 86%) were that the continual updating process should be maintained. Only three assessments (5%) deemed that searches should be conducted monthly; 3-monthly (14, 25%), 6-monthly (13, 23%) and yearly (17, 30%) searches were far more frequently recommended. Rarely (9, 16%) were topics deemed to meet all three criteria for living review. The vast majority of assessments (45, 79%) deemed the topic a priority for decision-making. Nearly half indicated that there was uncertainty in the available evidence or that new evidence was likely to be available soon. Since 2017, all but four of the assessed topic areas have had additional studies included in the evidence summary. For eight topics, there have been changes in recommendations, and revisions are underway for an additional six topics. Clinical importance was the most common reason given for why continual evidence surveillance should be undertaken. Workload for reviewers was a concern, particularly for topics where there is a steady flow of publication of small trials.

Our study found that participants felt that the vast majority of topics assessed in the Living Stroke Guidelines should be continually updated. However, only a fifth of topic areas were assessed as conclusively meeting all three criteria for living review, and the definition of "continual" differed widely. This work has informed decisions about search frequency for the Living Stroke Guidelines and form the basis of further research on methods for frequent updating of guidelines.