Intravascular Complications of Central Venous Catheterization by Insertion, health and medicine homework help

Below is an attached copy of the study
Complete and unaffected by observation–Is the follow-up of participants nearly 100% complete (did the same number of participants who started the study end the study—or did the authors tell you what happened to them) and is it affected by the participants’ or the investigators’ knowledge of the study or control group assignment?
Explain what a HR of 3.5 means.
What is the correct interpretation of the CI and the p value?
Extrapolation– To similar individuals, groups or populations—The authors should not discuss extending the conclusions to individuals, groups, or populations that are different than those who participated in the investigation. Do they?
Subgroups—Are the outcomes observed in subgroups within the investigation different from outcomes observed in the overall investigation? Look for pre-specified groups or groups that emerged when the numbers were crunched. Watching this week’s video lecture will help you answer this question.
Cost—To the best of your ability determine whether the study results justify the cost of the intervention