A high-level specification for adaptive ecological momentary assessment: real-time assessment of drug craving, use and abstinence.

In psychological research, efforts to capture day-to-day human experience traditionally relied on pen-and-paper diaries and questionnaires. Some current studies, however, incorporate handheld computers, which provide researchers with many options and advantages in addition to providing more reliable data. One advantage of using handheld computers is the programmability of the electronic diary, which, compared to old-fashioned paper diaries, affords the researchers with a wealth of possibilities. An important possibility is to construct a built-in mechanism in the computer-administered questionnaires that would allow transparent branching, in which question presentation is contingent on participants' answers to previous questions. The major hurdle in implementing such an approach is the limitations of the platform used for such assessments: inexpensive "low-end" handheld devices. We propose a high-level specification which enables non-programming researchers to "branch" their questionnaires without modifications to the source code in a highly user-friendly fashion, with backtracking capability and very modest hardware requirements. A finite state automaton approach was implemented, we believe for the first time, to create an auto-trigger mechanism for the real-time evaluation of the conditions. This solution provides our investigators with the capacity to administer efficient assessments that are dynamically customized to reflect participants' behaviors without the need for any post-production programming.