Understanding the Hawthorne effect

Researchers investigated the effectiveness of patient controlled analgesia for patients presenting to emergency departments with pain from traumatic injuries. A randomised controlled trial with a parallel groups study design was used. The control treatment was usual care, with analgesia titrated by nurses according to hospital guidelines. The participants were patients aged 18-75 years presenting to the emergency department who required intravenous opioid analgesia for the treatment of moderate to severe pain resulting from traumatic injuries, and who were expected to be admitted to hospital for at least 12 hours. In total, 200 adults were recruited and randomised to the intervention (patient controlled…