Kaplan-Meier Survival Curves

Question 1

what is time to event (survival) data

Answer 1

Time taken to achieve outcome:
Recovery (favourable) e.g. following surgery;
Death (adverse) e.g. Treatment for cancer

Question 2

what is a kaplan-meier survival curve?

Answer 2

Picture of group experience (time until outcome).

Probability (percentage) of outcome versus time.

Question 3

why are KM curves important?

Answer 3

Compare treatment options.
Estimate prognosis (e.g. ten-year survival rates).

Question 4

are favourable outcomes plotted up or down?

Answer 4

up

Question 5

what is a censored data?

Answer 5

no end data for the patient e.g they didn’t complete the study or died. Data up to the point of censoring is used

Question 6

explain how you use hazard ratio in a sentence (HR=1.9)

Answer 6

for the intervention group they are 1.9 times more likely to return to work at any point during the study

OR

for the intervention group, they are 90% more likely to return to work t any point during the study

Question 7

are adverse outcomes plotted up or down

Answer 7

down

Question 8

explain HR 0.80 (study is related to cancer treatment) in a sentence

Answer 8

at any point in time the G group are 20% less likely to achieve the outcome (die) than the C group.

Question 9

things to consider when discussing prognosis

Answer 9

Prepare for the discussion
Check facts;
Ensure appropriate environment.

Relate to the person
Develop rapport and show empathy

Elicit patient and care-giver preferences
Clarify baseline understanding;
Check what patient wants to know.

Provide Information:
Pace the information;
Use clear language;
Explain uncertainty, limitations and unreliability of prognostic estimates;
Ensure consistency of information.

Acknowledge emotions and concerns/ distress.

Foster ‘realistic’ hope:
But avoid giving unrealistic or false information.

Encourage questions
Check patient’s understanding;
Be prepared for further discussions in the future.

Document
Write a clear summary in medical notes;
Communicate with other professionals.