Devising and validating a headache diary in a series of patients with chronic daily headache from colombia Diseño y validación de un diario de cefalea en pacientes con cefalea crónica diaria en Colombia

1 Neurologist at Hospital Santa Clara E.S.E., Bogotá, Colombia; 2 Neurologist at Hospital El Tunal, E.S.E. and Clinica Carlos Lleras Restrepo, Bogotá, Colombia; 3 Resident of Clinical Neurology at the Universidad Nacional de Colombia, Bogotá, Colombia; 4 Neurologist at Clinica Carlos Lleras Restrepo, Bogotá, Colombia; 5 Neurologist at Clinica Carlos Lleras Restrepo; Assistant Professor at the Unit of Clinical Neurology and Centre for Epidemiological Research at Universidad Nacional de Colombia, Bogotá, Colombia. Correspondence: Gabriel F. Torres; Departamento de Medicina Interna. E.S.E. Hospital Santa Clara; Carrera 15 No. 1 – 59 Sur, Bogotá – Colombia; E-mail: [email protected] Support: This study was partially funded by the Colombian Association of Neurology (Asociación Colombiana de Neurología). Conflict of interest: There is no conflict of interest to declare. Received 06 July 2011; Received in final form 16 August 2011; Accepted 24 August 2011 AbstrAct Objective: To devise and test the reliability and validity of a brief headache diary in a series of Colombian patients with chronic daily headache. Methods: The study was designed in five stages: selection of domains (group of patients and experts); initial devising of the items (writing group); identification of non-understandable items (n=20); assessment of internal consistency (n=100); assessment of validity and assessment of sensitivity to change during seven consecutive days (n=25, 175 observations). Results: Five domains were selected: headache presence, severity and length of pain, analgesics intake, and missing workdays. The headache diary is internally consistent (≈75% of rotated variance), correlates with the medical interview (Spearman’s rho and Kendall’s tau over 0.8 for each domain) and it has an adequate and stable sensitivity and specificity (82 to 96%). Conclusions: This headache diary is a reliable and valid instrument and represents the most important features affecting Colombian patients with chronic daily headache.