What is the {measure} for {studied by} of {epidemiology}
What is the topic of study of epidemiology ?
 select distinct ?sbj where { ?sbj wdt:P2579 wd:Q133805 . ?sbj wdt:P31 wd:Q39875001 } 
select distinct ?subj where { ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?subj . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P2579> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q133805> . ?subj <http://www.wikidata.org/entity/P31> <http://wikidata.dbpedia.org/resource/Q39875001> } 
Epidemiology is the study of what?