OBJECTIVE: To determine the value of conjunctival pallor in ruling in or ruling out the presence of severe anemia (hemoglobin < or = 90 g/L) and to determine the interobserver agreement in assessing this sign. DESIGN: Patients were prospectively assessed for pallor by at least one of three observers. All observations were made without information of the patient's hemoglobin value or of another observer's assessment. SETTING: Tertiary-care, university-affiliated teaching hospital. PATIENTS: Three hundred and two medical and surgical inpatients. MEASUREMENTS AND MAIN RESULTS: Likelihood ratios (LRs) calculated for conjunctival pallor present, borderline, and absent were as follows: pallor present, LR 4.49 (95% confidence interval [CI] 1.80, 10.99); pallor borderline, LR 1.80 (95% CI 1.18, 2.62); pallor absent, LR 0.61 (95% CI 0.44, 0.80). Kappa scores of interobserver agreement between paired observers were 0.75 and 0.54. CONCLUSIONS: The presence of conjunctival pallor, without other information suggesting anemia, is reason enough to perform a hemoglobin determination. The absence of conjunctival pallor is not likely to be of use in ruling out severe anemia. With well-defined criteria, interobserver agreement is good to very good.