Electronic Diaries: Appraisal and Current Status.

The recent explosion of technology has moved the field of patient reported outcomes (PROs) into a new era. Use of paper-and-pencil questionnaires administered before and after treatment has been eclipsed by highly sophisticated random prompts for symptom ratings at multiple points throughout the day, a method known as ecological momentary assessment (EMA). During the last 25 years, research has demonstrated that retrospective ratings are subject to a variety of cognitive heuristics that can distort the report. Initially, this was addressed by adopting paper diary protocols involving multiple ratings in a day or across a week. Technology was also advancing, and some researchers began to utilize electronic platforms for EMA assessment. A good deal of research has been conducted comparing paper and electronic formats. Issues of compliance have been particularly problematic for paper diaries. Electronic technologies can be expensive and require expertise in programming and data management. Not all research questions will require intensive momentary assessment, and end-of-day ratings may be adequate for many applications. What is required of the investigator is familiarity with the strengths and weaknesses of the methods and platforms available as well as a reasoned decision to elect a particular methodology for the study question at hand.