Fig. 1From: Quantifying cognition at the bedside: a novel approach combining cognitive symptoms and signs in HIVDistribution of individuals with lowest to highest “cognitive ability” (top) and of item thresholds (bottom). The mean ability of the persons in this sample is 1.9 logits, a value above the mean location of items (0 logit) and with the best measurement precision occurring around 0.8 logits. One person was removed for non-fit. There is no floor or ceiling effectBack to article page