\documentclass[../Main.tex]{subfiles}
\graphicspath{{\subfix{Assets/img/}}}

\begin{document}
% Introduce clinicaltrials.gov
% - Describe different statuses 
% - status flowchart
% Introduce causal model
% - Diagram
% - List each node and what they influence (and why)
% Begin Discussing Data
% - Where did I get data for each node?

When any clinical trial is conducted, it goes through three distinct stages:
pre-trial, active, and decision to conclude.
In figure \ref{Fig:Stages}, you can see the component parts of each stage. 

\begin{figure}[H] %use [H] to fix the figure here.
    \includegraphics[width=\textwidth]{../assets/img/ClinicalTrialStagesAndStatuses}
    \caption{Model of Statuses}
    \label{Fig:Stages}
\end{figure}

In the pre-trial stage, the sponsoring organization chooses to run the trial,
they register the trial on  \url{ClinicalTrials.gov}, and then decide if they
will begin enrollment. 
Many registered trials are withdrawn at this point, before the trial has opened
for enrollment. 
Once enrollment has opened 

Because running randomized experiments on companies running clinical trials 
is unlikely to to happen anytime soon, 
causal identification will depend on observational methods. 
I use the do-calculus approach developed by Judea Pearl
\cite{pearl_CausalityModels_2009}
to describe what affects the success of a Phase III clinical trial. 
I then use that model to derive the econometric model capable of estimating
the effect of extending the recruiting period or of having an additional 
competing drug.



% In \cref{Fig:CausalModel} I diagram the directed acyclic graph that describes
% the data generating model.
The proposed data generating model consists of a decision maker
-- the study sponsor --
who must decide whether to let a trial run to completion or terminate
the trial early. 
While receiving updates regarding the status of the trial, they try to 
answer questions such as:
\begin{itemize}
    \item Do I need to terminate the trial due to safety incidents?
    \item Does it appear that the drug is effective?
    \item Are we recruiting enough participants to achive the statistical
        results we need?
    \item Does the current market conditions and expectations about 
        returns on 
        investment justify the expenditures we are making?
\end{itemize}
Althought I treat this as a single agent, in reality, there are multiple 
stakeholders involved in chosing whether the trial should continue, including
those running the trial (which may be a separate firm), 
the company developing the drug, additional rightsholders, 
or funding organizations.

% When appropriate, the study sponsor terminates the trial.
% If there are not enough issues to terminate the trial, it continues until it 
% is completed.

In the United States, clinical trials are required by law to be registered on 
\url{ClinicalTrials.gov}, where they are made available to the public. 
Trials must be registered 

% 


\end{document}
