A new diary has been developed for patients with sickle cell disease (SCD) that allows them to record vaso-occlusive crises (VOC)-related pain crises without needing to visit a health care professional.

The diary was included in the Evaluation of Longitudinal Pain Study in Sickle Cell Disease study and reported in the European Journal of Haematology, and is expected to more accurately reflect the actual occurrence of VOCs than do reports made only at medical visits.

“In clinical trials, VOC episodes historically have required medical utilization for a VOC episode to be recorded and counted,” the authors wrote. “However, the majority of painful VOC episodes are often managed by patients at home; therefore, the medical utilization definition of a VOC episodes likely captures only a subset of the VOCs that patients experience.”

Both the American Society of Hematology and the US Food and Drug Administration have recommended the development of daily patient-reported outcome measures assessing SCD pain, affect, and functioning, to be able to more accurately assess the endpoints of clinical trials on SCD treatments.

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A total of 35 patients aged 12 years or older with SCD participated in the study and completed a daily diary on a secure, electronic handheld device. The diary included a description of pain crises and details such as the worst pain, fatigue, and functioning. A subset of patients and caregivers were interviewed to assess their understanding of the questions in the diary.

The participants reported being able to use the SCD diary confidently to report VOC-related pain crises. The analysis of the responses showed that the diary is effective at capturing the complete patient experience of these events. The research team expects the diary will allow future studies to more accurately evaluate the efficacy of new SCD treatments in terms of reducing VOC-related pain crises.


Coyne KS, Currie BM, Callaghan M, et al. Validation of patient-reported vaso-occlusive crisis day as an endpoint in sickle cell disease studies. Eur J Haematol. Published online May 15, 2022. doi:10.1111/ejh.13790