Table 1. Details of the development and factors included in each of the risk scores included in validation study.
| Genetic risk score | Genetic plus phenotypic risk score | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Author, year | Country | Number of SNPs | Method of development of GRS | Developed in original publication as a “genes-only” score | Method of development of combined model | Non-genetic risk factors included in score | |||||
| Age | Sex | FH | BMI | Smoking | Other | ||||||
| Abe 2017 | Japan (d, v) | 11 | Unweighted allele counting model | Logistic regression | • | • | • | • | • | Referral pattern, alcohol consumption, regular exercise, and dietary folate intake | |
| Dunlop 2013 | UK, Canada, Australia, USA and Germany (d) Sweden and Finland (v) | 10 | Weighted allele model weighted by published log odds | • | Stratified absolute risks calculated using logistic regression applied to Scottish data | • | • | • | |||
| Frampton 2016 | UK (v) | 37 | Weighted allele model weighted by published log odds | • | |||||||
| Hosono 2016 | Japan (d, v) | 6 | Unweighted allele counting model | Logistic regression | • | • | • | • | Referral pattern, alcohol consumption, regular exercise, dietary folate intake | ||
| Hsu 2015 | USA and Germany (d, v) | 31 | Weighted model weighted by published log-odds | ||||||||
| Huyghe 2019 | European (91.7%) and East Asian (8.3%) (d) | 120 | Weighted allele model weighted by study derived weights | • | |||||||
| Ibanez-Sanz 2017 | Spain (d, v) | 21 | Unweighted allele counting model (weighted allele models weighted by published log-odds and study derived log-odds similar so not reported) | • | Logistic regression | • | • | Alcohol use, physical exercise, red meat and vegetable intake, NSAIDs/aspirin use | |||
| Iwasaki 2017 | Japan (d, v) | 6 | Weighted allele model weighted by study derived log- transformed per allele HR | Weighted cox proportional hazards regression | • | Developed in men only | • | • | Alcohol | ||
| Jenkins 2016 / 2019 | Weighted allele model weighted by published log odds | 49 | Weighted allele model weighted by published log odds | • | • | ||||||
| Jeon 2018 | Australia, Canada, Germany, Israel and USA.(d, v) | 63 | Weighted allele model weighted by study derived estimated regression coefficients | Logistic regression | Developed separately in women and men | • | • | Height, education, history of type 2 diabetes mellitus, alcohol consumption, regular aspirin use, regular NSAID use, smoking, intake of fibre, calcium, folate, processed meat, red meat, fruit, vegetables, total-energy, physical activity (both) HRT (women) | |||
| Smith 2018 | UK (d, v) | 42 | Weighted allele model weighted by published log odds | • | Log GRS combined with predicted log hazard ratio from original model | • | • | • | • | Diabetes, multi-vitamin usage, years of education, alcohol intake, physical activity, NSAID usage, red meat intake, smoking, oestrogen use (women only) | |
| Wang 2013 | Taiwan (d, v) | 16 | Logistic regression / GRS based on genotypes not alleles | • | |||||||
| Xin 2018 | China (d, v) | 14 | Weighted allele models weighted by published log odds and by study derived weights | • | |||||||
| Yarnall 2013 | UK (v) | 14 | Weighted allele model / developed with a simulation based procedure using REGENT software | • | OR estimated from simulation based procedure using REGENT software | • | • | Alcohol, fibre intake, red meat intake, physical activity | |||
CRC - colorectal cancer, SNP - single-nucleotide polymorphism, BMI - body mass index, NSAID - non-steroidal anti-inflammatory drug, GRS - genetic risk score. d = development; v - validation