Compared to RCTs, collecting information from routine care in registries and other data collections offer a number of advantages. Often registries have wide in- and exclusion criteria, resulting in high patient numbers. This allows to include patient conditions and subpopulations often excluded in RCTs, and to detect rare complications. Depending on the character of the registry, it might follow changes in clinical care timely (e.g., after implementation of guidelines of introduction of new drugs), and it allows comparisons between regions, countries, continents and populations, thus mirroring the “Real World”. On the other hand, analyses with registry data have to carefully consider uncontrolled and/or undetectable confounders. Quality of registry data depends on resources, staff training and motivation, and data quality is often not as closely monitored as in many RCTs. Moreover, primary objective of data collections might bias its content (e.g., data collected for reimbursement of care givers). Most importantly, as interventions in registry / routine data collections are not randomized, associations with outcomes should be interpreted with care.
QUIPS and PAIN OUT form a large registry in postoperative pain management with data from several 100 hospitals and more than 500,000 patients. They comprise PROMs and clinical data from the immediate perioperative phase, with additional modules allowing patients’ follow-up for several months postoperatively. Chances and limitations of such registry data for clinical research will be addressed in the talk by discussing the following topics:
- What do registry data tell us?
- Limitations of registries
- Real world and RCTs