Perform critical appraisal of this paper by Kannus et al. by responding to the following questions: 1. What was the purpose of the study? Was the design appropriate for the purpose of the study? 2. What is the study factor? 3. Was the assignment of patients to treatments randomised? 4. Were patients analysed in the groups to which they were randomised? 5. Were patients, health workers, and study participants ‘blind’ to treatment? 6. Were the groups similar at the start of the trial? 7. Apart from the experimental intervention, were the groups treated equally? 8. Was follow-up completed? 9. What were the outcomes? 10. What was the target population? Did the sample represent the target population?