School bullying is sometimes identified using the K-PNI. The K-PNI is based on the Peer Nomination Inventory (PNI) developed by Wiggins and Winder to determine implicit or explicit judgments about peers as part of the examination of children's social maladjustment. To complete the questionnaire, children were asked to name classmates of the same sex who fit the behavioral type described in each item. The nomination of multiple individuals for each item was allowed. The median score on the PNI represents a natural break in the distribution that identifies children as having been nominated in a given category.