A card study is a method for collecting real world data from practice. In a typical card study, a clinician gathers a small amount of data on a card based on a clinical encounter. Data are shared with a central facility and the analysis results shared with study participants and with larger audiences.

The card study method was pioneered by the Ambulatory Sentinel Practice Network (ASPN), and the method has been expanded by other practice-based research networks. An IRB protocol for streamlining human subject protection for multiple card studies in a network has been developed.

Research questions particularly amenable to the card study method typically focus on simple and easily observable phenomena, such as disease incidence/prevalence, practice patterns, or clinical behaviors, for which data are not readily obtained from other sources such as medical records or surveys. A typical card study specifies inclusion criteria and a study time frame and/or number of observations by each participating clinician.

This app is designed to provide a vehicle for investigators to design a card study on a computer, invite participants, and to receive data back in real time, and for clinicians to participate by accepting an invitation and then collecting data on a smartphone.