Reproducibility of the University of Toronto self-administered questionnaire used to assess environmental sensitivity

Environmental sensitivity patients report symptoms provoked by low-level ex posure to a wide range of substances. Features of published case definition s include nature of onset, chronicity, symptom provocation by multiple subs tances, symptom provocation by an escalating number of exposures, involveme nt of multiple body systems including the nervous system, provocation by un related substances, and addictive behaviors. This study assessed the reprod ucibility of a Canadian self-administered questionnaire, the University of Toronto Health Survey, designed to determine the prevalence of the features described in these case definitions. A total of 191 eligible respondents a ged 16-70 years who attended several types of medical practices in 1994 wer e invited to complete a second questionnaire 5-7 months after the first; 13 4 (70.2%) complied. Total agreement on whether patients satisfied each of s even case definitions ranged from 80% to 90%. After adjustment for chance, major agreement was observed for three of the seven case definitions (kappa = 0,69, 0.68, and 0.78), The survey achieved good reproducibility regardin g self-report of symptoms described in published case definitions of enviro nmental sensitivity.