The user calls into a dedicated phone line, and hears a spoken script that details the question, and the possible responses.
Diaries are used when it is desirable to obtain frequent assessments over a period of time, for example when a condition fluctuates in severity.
Systems generally transfer data promptly to a central server, allowing tailored feedback to be given to patients.
Electronic diaries also eliminate the need for manual editing and entry of data, time-consuming and error-prone processes.
The questionnaires used in site-based ePRO are often longer and more complex than those used in diaries, assessing quality of life and activities of daily living, for example, in some detail.
This is important, as if significant numbers of patients refuse to take part in clinical trials because of dislike of computers then there will be bias in the study population.
The International Society for Pharmacoeconomics and Outcomes Research (ISPOR) has issued guidelines on establishing an equivalence between modes of administration.
[13] Their approach is hierarchical and depends on the degree of change made during the process of migration from paper to electronic format.
At the lowest level, where the least change has been made, cognitive interviewing of patients as a check that they construe ePRO and paper, in the same way, is sufficient.
This general finding, of course, does not guarantee that any specific migration will lead to equivalence, and each case must be reviewed and documented.
More commonly, perhaps, new instruments will be developed in parallel for paper and electronic use, as is the case with the PROMIS (Patient-Reported Outcomes Measurement Information System) initiative.
Several successful regulatory approvals have used ePRO data in recent years, including ketorolac for ocular pain, eszopiclone for insomnia, milnacipran for fibromyalgia, estradiol/levonorgestrel for post-menopausal symptoms, and ruxolitinib for myelofibrosis.
[16] In the case of estradiol/levonorgestrel, detailed ePRO data on bleeding/spotting from a one-year clinical trial are presented in the patient information leaflet.
This allows clinic staff to monitor outpatients, and to identify the occurrence of adverse reactions that may require intervention.