The original instructions for the Edinburgh Handedness Inventory are misunderstood by a majority of participants.

The Edinburgh Handedness Inventory (EHI) is the most widely used handedness inventory. This study examined the rate at which the EHI instructions were followed using a large sample (n = 423) of males who were administered the instrument. Using liberal criteria for response coding, it was determined that only 47.3% were able to follow the instructions completely. This is in contrast to 88.2% successfully following instructions on a different, Likert-style instrument administered concurrently. Participants' level of education and handedness significantly predicted their adherence to instructions. Implications for the use of the EHI are discussed.