KARACHI: One in four children aged three to eight years in Karachi’s public schools are at risk of social, emotional, physical, language and cognition development delays, a study conducted by the Aga Khan University (AKU) said on Wednesday. AKU said it conducted the research among children studying in grades one and two at Karachi’s public schools. The children were measured in each of the five developmental domains — social and emotional, physical, language, cognition and communication skills.