This research aims to evaluate the Web Content Accessibility Guidelines Evaluation Methodology (WCAG 1.0-EM), as proposed by the W3C to evaluate accessibility of electronic sites for verifying compliance with the Web Content Accessibility Guidelines (WCAG) 2.0. Previous research has shown that different evaluator profiles can generate different results in accessibility assessments. Exploratory surveys were conducted which reinforced the need for accessibility evaluators have a minimum of expertise profile. An online questionnaire was used to recruit people who had already done accessibility evaluations, with questions about education, profession, techniques and evaluation tools, disabilities, assistive technologies and review of different definitions of accessibility. From 83 respondents, 62 claim to have already performed evaluation of accessibility, and 25 met the minimum defined profile to be qualified for accessibility evaluation phase of the Brazilian Health Portal home page (Portal da Saúde). The evaluation was made by nine of the selected evaluators through electronic questionnaire based on the requirements and support texts of WCAG-EM 1.0 steps. A cooperative evaluation through Skype software with blind users was also conducted in order to collect problems of interaction of these users with the Brazilian Health Portal. A comparison was made between the problems encountered by different evaluators and a comparison of the problems faced by blind users with those reported by the evaluators. The results showed that steps of WCAG-EM 1.0 generate very different interpretations by the evaluators and favored inconsistencies observed between the answers. There was also little relationship between the problems encountered by the evaluators and those observed in the evaluation with blind users. The results allowed the generation of improvement recommendations for further development of WCAG-EM 1.0.