2.2. Search strategy

Embase, Pubmed, and Google scholar will be comprehensively searched up to the 1st September 2019, and supplemented with manual searches of the included reference lists to identify cohort studies. Search strategies will be developed and reviewed by 2 experienced librarian investigators. Any discrepancy is resolved by consensus. An example of search string for Pubmed is shown as follow:

#1 (((((“Blood Glucose”[Mesh]) OR “Glucose Intolerance”[Mesh]) OR “Prediabetic State”[Mesh]) OR “Hyperglycemia”[Mesh]) OR “Hemoglobin A, Glycosylated”[Mesh])

#2 (((((((((((“Prediabetic State”[Text Word]) OR Hyperglycemia[Text Word]) OR “impaired fasting glucose”[Text Word]) OR “impaired glucose tolerance”[Text Word]) OR “pre-diabetes”[Text Word]) OR prediabetes[Text Word]) OR “borderline diabetes”[Text Word]) OR “higher risk of diabetes ”[Text Word]) OR “ high risk of diabetes”[Text Word]) OR hemoglobin A1c [Text Word]) OR HbA1c[Text Word])

#3 #1 OR #2

#4 ((((“Cardiovascular Diseases”[Mesh]) OR “Mortality”[Mesh]) OR “Death”[Mesh]) OR “Fatal Outcome”[Mesh])

#5 (((((((((“ischemic heart disease”[Text Word]) OR “myocardial infarction”[Text Word]) OR “cardiovascular events”[Text Word]) OR “cerebrovascular disease”[Text Word]) OR “stroke”[Text Word]) OR “cerebral infarction”[Text Word]) OR Mortality[Text Word]) OR fatal[Text Word]) OR death[Text Word])

#6 #4 OR #5

#7 (((“Coronary Diseases”[Mesh]) OR “Coronary Artery Disease”[Mesh]) OR “Heart Disease”[Mesh])

#8 ((((((PCI [Text Word]) OR revascularization [Text Word]) OR invasively [Text Word]) OR intervention [Text Word]) OR angioplasty [Text Word]) OR “percutaneous coronary intervention”[Text Word])

#9 #7 OR #8

#10 #3 AND #6 AND #9

#11 animals [MeSH Terms]

#12 humans [MeSH Terms]

#13 #11 NOT #12

#14 #10 NOT #13

#15 (“Risk”[Mesh]) OR risk [Text Word]

#16 #14 AND #15

#17 (((((((((((epidemiologic studies[MeSH Terms]) OR cohort studies[MeSH Terms]) OR “epidemiologic”[Text Word]) OR “cohort”[Text Word]) OR “longitudinal”[Text Word]) OR “follow up”[Text Word])) OR observational[Text Word]) OR prospective[Text Word])

#18 #16 AND #17