What Is the Most Important Assumption in This Type of Analysis

question 7

Multiple Choice

What is the most important assumption in this type of analysis? Use the following table to answer the question. Survival of Patients With Metastatic Cancer Z Following Diagnosis
$\begin{array}{l|l|l|l|l|l|l|l}\begin{array}{l}\text { Interval } \\\text { since } \\\text { beginning } \\\text { treatment } \\\text { (months) }\end{array} & \begin{array}{l}\text { Alive at } \\\text { beginning } \\\text { interval }\end{array} & \begin{array}{l}\text { Died } \\\text { during } \\\text { interva } \\1\end{array} & \begin{array}{l}\text { Withdre } \\\text { whterval }\end{array} & \begin{array}{l}\text { Effective } \\\text { number } \\\text { exposed } \\\text { to risk of } \\\text { dying }\end{array} & \begin{array}{l}\text { Proporti } \\\text { on who } \\\text { died } \\\text { during } \\\text { interval }\end{array} & \begin{array}{l}\text { Proportion } \\\text { who did not } \\\text { die during } \\\text { interval }\end{array} & \begin{array}{l}\text { Cumulative } \\\text { proportion } \\\text { who } \\\text { survived } \\\text { from } \\\text { enrollment } \\\text { to end of } \\\text { interval }\end{array} \\\hline x & I_{x} & d_{x} & W_{x} & I_{x}^{\prime} & q_{x} & p_{x} & P_{x} \\\hline 1-12 & 200 & 10 & 40 & & & & \\\hline 13-24 & 150 & 20 & 30 & & & & \\\hline 25-36 & 100 & 30 & 20 & & & & \\\hline 37-48 & 50 & 40 & 10 & & & & \\\hline\end{array}$

• A) There has been no secular (temporal) change in the effectiveness of treatment or in survivorship over calendar time.
• B) The effect of treatment has improved during the period of the study.
• C) The survival experience of people who are lost to follow-up is better than the experience of those who are followed up.
• D) The survival experience of people who are lost to follow-up is worse than the experience of those who are followed up.
• E) An equal number of men and women enrolled each year.

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