This investigation evaluated the validity and precision of clinical criteria for dengue fever using as a gold standard the ELISA-GEL serological test (IgM specific for dengue). A total of 201 patients; 100 serologically confirmed cases and 101 negative “controls” were included in the study. A clinical standardized criterion (EMI) used in Venezuela and the one recommended by PAHO/WHO were compared to serological results by calculating the sensitivity, specificity, predictive values, their 95% confidence intervals and their statistical significance by using the chi square test. The inter-rater agreement and Kappa were also calculated for the clinical criteria. Results can be summarized as follows: The inter-observer agreement was 84% and Kappa 63% for the clinical diagnosis. The sensitivity and specificity were 88.8%, 59.4% and 87.0%, 26.7% for EMI and WHO criteria respectively. Positive and negative predictive values were 68.2%, 83.3% and 53.8%, 65.9% for EMI and WHO criteria respectively (prevalence=49.8%). Laboratory results such as platelet levels and hemoconcentration were important diagnostic aids that can improve considerably the diagnostic ability of the clinical criteria. The Venezuelan (EMI) and WHO clinical criteria were found to be insufficient for an accurate diagnosis. Serological tests should be used to confirm clinical findings. Less rigorous clinical criteria were found to have a much higher positive predictive value at the expense of a low negative predictive ability. Such criteria may be used for screening purposes.
Learning Objectives: At the end of the presentation the participant will be able to 1. Describe the basic epidemiology of Dengue Fever. 2. Describe major clinico-epidemiologic features of Dengue Fever. 3. Understand the methodology used to assess different clinical criteria for screening and diagnosis of Dengue Fever. 4. Undestand how to use the tools to evaluate inter-rater agreement in the diagnosis of Dengue Fever. 5. Appreciate the urgency to study new means for screening and diagnosis of Dengue Fever.
Keywords: Epidemiology,
Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: None
Disclosure not received
Relationship: Not Received.