Hello everyone,

I intend to analyse panel data (long format) on effects of individuals taking a particular food item "FO" over time on blood sugar.
information on the start date and end dates are given for each particular food item for each individual. However,
the a series of lab tests (FBS-fasting blood sugar) were taken between each start and end of each food item.
My aim is to conduct survival analysis and also calculate the incidence rates of hyperglycemia (High blood sugar) .
How do I merge this data so that I capture all the lab tests?


Dataset 1: food items taken

Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input str12 id_patient str36 regimen long(food_start_date food_end_date) 
"022-5555" "     FO" 17342 18216 
"022-5555" "     FO" 18216 18596 
"022-5555" "     TO" 18596 18764 
"022-6256" "     TO" 19970 20495 
"022-6256" "     TO" 20495 20507 
"022-6256" "DEFAULT" 20507 21473 
"022-6256" "     TO" 17609 17784 
"022-6256" "     FO" 17784 18226 
"022-6256" "     FO" 18226 18301 
"022-6256" "     FO" 18301 18486 
"022-6256" "     TO" 18486 21300
end
format %d food_start_date
format %d food_end_date
Dataset 2: lab test

Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input str12 id str10 fbs_test long test_date 
"022-5555" "FBS"  8.1 17336 
"022-5555" "FBS" 10.0 17584
"022-5555" "FBS" 13.2 17765
"022-5555" "FBS"  4.6 18010
"022-6256" "FBS"  3.3 16459
"022-6256" "FBS"  7.8 17668
"022-6256" "FBS" 15.6 18053
"022-6256" "FBS"  6.6 18334
"022-6256" "FBS"  7.8 18817
"022-6256" "FBS"  8.8 19172
"022-6256" "FBS" 10.2 19423
"022-6256" "FBS" 13.3 19662
"022-6256" "FBS" 15.3 19909
"022-6256" "FBS"  9.4 19909
end
format %d test_date