Shortcomings in rosacea diagnosis and classification

Extract

In 2002, the National Rosacea Society (NRS) proposed a provisional classification for rosacea based on the clinical knowledge of that time and on morphological features.1 Explicit was the intent that this was ‘a framework that could be readily updated and expanded as new discoveries were made’.1 That scheme posited primary and secondary criteria for diagnosis and division into four subtypes, representing common clinical patterns of presentation, and one variant.1 It also helped to increase recognition of rosacea as a disease and to guide research.

Subsequent incorporation of this paradigm in epidemiological, pathophysiological and translational research has provided for greater standardization in rosacea reporting. Now, after more than a decade of using this scheme in research and clinical practice, it should be re‐evaluated to incorporate current scientific knowledge and address shortcomings in guiding diagnosis and classification of rosacea.

Unequivocal diagnoses can be challenging in the absence of an absolute gold standard (histology in malignancy; reduced ejection fraction in congestive heart failure; positive bacterial blood cultures in sepsis). Accuracy of a diagnostic test is based on the proportion of true results of the test (true positive, or sensitivity; and true negative, or specificity) in a population.