SQL & PL/SQL :: How To Obtain Data Returned By Function When Executed Using Dynamic Query

I'm attempting to use dynamic SQL to execute a function that returns a user-defined collection. The problem is that I don't know how to use dynamic SQL to handle user-defined types...or if this is even possible?

The code I have is as follows:

CREATE OR REPLACE PACKAGE qi_test IS

TYPE typ_qi_data IS RECORD(
iQIFlag NUMBER(1),
iIPFlag NUMBER(1),
iRiskIndicator NUMBER(1),
iDenominator NUMBER(8),
iNumerator NUMBER(8)
[code]........

I want to be able to execute the above function using dynamic SQL. Initially tried:

DECLARE
f2_data qi_test.typ_qi_data_tab;
BEGIN
EXECUTE IMMEDIATE 'begin :1 := qi_test.get_f2_data; end;'
USING OUT f2_data;
[code]......

...but this just produces "PLS-00457: expressions have to be of SQL types". So it looks like I can't do it this way if the returned data type is user defined. I know it would be easier in this instance to just use something like:

f2_data := qi_test.get_f2_data;

...rather than EXECUTE IMMEDIATE, but it's the principle that I need to get right as it forms part of a much bigger piece of work.