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A qualitative review of the psychometric properties and feasibility of electronic headache diaries for children and adults: where we are and where we need to go.

BACKGROUND
While paper headache pain diaries have been used to determine the effectiveness of headache treatments in clinical trials, recent advances in information and communication technologies have resulted in the burgeoning use of electronic diaries (e-diaries) for headache pain.


OBJECTIVE
To qualitatively review headache e-diaries, assess their measurement properties, examine measurement components and compare these components with recommended reporting guidelines.


METHODS
The databases Medline, the Cumulative Index to Nursing and Allied Health Literature, Embase, PsychInfo, the Education Resources Information Centre and ISI Web of Science were searched for self-report headache e-diaries for children and adults. A total of 21 publications that involved e-diaries were found; five articles reported on the development of an e-diary and 16 used an e-diary as an outcome measure in randomized controlled trials or observational studies. The diary measures' components, features and psychometric properties, as well as the quality of evidence of their psychometric properties, were evaluated.


RESULTS
Five headache e-diaries met the a priori criteria and were included in the final analysis. None of these e-diaries had well-developed evidence of reliability and validity. Three e-diaries showed evidence of feasibility. E-diaries with ad hoc measures developed by the study investigators were most common, with little to no supportive evidence of reliability and⁄or validity. Compliance with the reporting guidelines was variable, with only one-half of the e-diaries measuring the recommended primary outcome of headache frequency.


CONCLUSIONS
Specific recommendations regarding the development (including essential components) and testing of headache e-diaries are discussed. Further research is needed to strengthen the measurement of headache pain in clinical trials using headache e-diaries.