The AB Design can be used to quickly assess the effects of an experimental variable. Its main disadvantage its inability to distinguish the experimental effect from possible confounds that might occur coincident with the change of condition.
ceÂ·liÂ·ac disÂ·ease. A disease occurring in children and adults characterized by sensitivity to gluten, with chronic inflammation and atrophy of the mucosa of the upper small intestine; manifestations include diarrhea, malabsorption, steatorrhea, and nutritional and vitamin deficiencies.
n. 1  A chronic gastrointestinal disease characterized by sensitivity to gluten and malabsorption from the small intestine, resulting in diarrhea, stools with high fat content, and nutritional and vitamin deficiencies. Also called celiac sprue, gluten-sensitive enteropathy, nontropical sprue.