The reliability and validity of a structured interview for the assessment of infectious illness symptoms.

Respiratory infections are the leading cause of morbidity in community populations. We developed a structured interview based on the Health Review (Rose et al., Psychosom. Med. 40: 142-165, 1978) to provide a simple method for periodic assessment of infectious illness, particularly upper respiratory infections. Congruence between interview data and physician diagnoses demonstrated excellent agreement regarding the presence or absence of an infection. Subjects who showed a clinically significant increase in antibody titers to an influenza virus vaccine reported fewer than half as many respiratory infections in the subsequent year as subjects who did not show a significant response. Interrater and test-retest reliabilities were satisfactory. These data support the reliability and validity of this method of assessing infectious illnesses.