Table 1 Study characteristics and quality assessment of studies included in systematic review of physical activity and risk of colorectal cancer with higher risk subgroups
First author, year | Age Range (years) | Country | Case-control: control sample & matching Cohort: study name | Physical activity period | Comparison of Physical Activity | Cancer Site/Number of Cases | Method of Case Confirmation | Assessment of Confounding | Subgroups analyzed | Method of Subgroup Assessment | |
|---|---|---|---|---|---|---|---|---|---|---|---|
Case-Control Studies | |||||||||||
 Boutron-Ruault, 2001 [28] | 30–79 | France | Population | No matching | Regulara, b | Sedentary vs. High (regular physical exercise) | Colorectal: 171 | Histological exam | Age and sex | FHCRC | Interview questionnaire |
 Boyle, 2012 [29] | 40–79 | Australia | Population | Frequency | Adulthood (≥19 years) | Definite vs. Never Resistance training | Colon: 552 Rectal: 318 | Histological exam | Age group, sex, resistance training in other age periods, lifetime moderate and vigorous non-resistance training rerecraetional physical activity, lifetime occupational activity and energy intake | BMI | Self-administered questionnaire |
 Gerhardsson de Verdier, 1990 [30] | 40–69 | Sweden | Population | Frequency | 1950-1985b | Very active vs. fairly active | Left colon: 147 | Histo-pathological diagnosis and ICD-7 codes | Year of birth and sex | BMI | Self-administered questionnaire |
 Hou, 2004 [31] | 30–74 | China | Population | Frequency | Lifetime | >94.3 MET-h/wk. vs. <48.3 MET-h/wk | Colon: 931 | Histo-pathology or other methods | Age, education, family income, marital status, total energy intake, intake of red meat, carotene and fiber, number of pregnancies and menopausal status | BMI | Interview questionnaire |
 Huang, 2004 [32] | ≥18 | Japan | Non-cancer outpatients | No matching | Regulara | ≥3 times/month vs. <3 times/month | Colorectal: 1352 | Medical data from the Aichi Cancer Center Hospital | Age, sex | FHCRC | Interview questionnaire |
 Mao, 2003 [33] | 20–76 | Canada | Population | Frequency | Past 2 years | ≥24.6 MET-h/wk. vs. <8.8 MET-h/wk | Rectal: 1447 | Histological exam | Age, province, education, total caloric dietary fiber, vegetable and fruit intake, smoking and alcohol consumption | BMI | Self-administered questionnaire |
 Parent, 2011 [34] | 35–70 | Canada | Population | Frequency | Overall activity in adult lifeb | Higher (active at work with recreational PA or very active at work) vs. Lower (sedentary at work or active at work without recreational PA) | Colon: 496 Rectal: 248 | Pathological confirmation | Age, socio-economic status, education, ethnicity, respondent status, smoking, alcohol/β-carotene (colon) and beer (rectum) | BMI | Interview questionnaire |
30–79 | USA | Population | Frequency | Lifetime | High (>1000 kcal/wk) vs. Low (0 kcal/wk) | Colon: 2073 | Pathology report | Age at diagnosis, FHCRC, BMI, dietary fiber and calcium, use of aspirin or NSAIDs, dietary cholesterol and energy intake | BMI and FHCRC | Interview questionnaire | |
 Zhang, 2006 [38] | 40–85 | USA | Population | Frequency | Adulthood | ≥2 times/wk. vs. <1 time/month | Colon: 685 | Histological exam | Age, sex, education level, dietary intake of fat and fiber and FHCRC | BMI | Self-administered questionnaire |
Cohort Studies | |||||||||||
 Ballard-Barbash, 1990 [39] | 30–62 | USA | Framingham Study | Regulara | High vs. low tertile of PA index | Colon: 152 | Medical history from cohort records | Age | BMI | Interview questionnaire | |
 Friedenreich, 2006 [16] | 35–70 | Europe | European Prospective Investigation into Cancer and Nutrition | Past year | Active vs. Inactive | Colon: 1094 | Population based cancer registries, health insurance records, pathology registries | Age, centre, energy and fibre intake, education, smoking | BMI | Self-report and clinical examination | |
 Larsson, 2006 [40] | 45–79 | Sweden | Cohort of Swedish Men (COSM) | Year before study enrolment | ≥60 min/day vs. <10 min/day | Colorectal: 496 | ICD-9 codes in the National and Regional Swedish Cancer registers | Education, FHCRC, history of diabetes, smoking and aspirin use | BMI | Self-administered questionnaire | |
 Lee, I., 1994 [41] | 30–79 | USA | Harvard Alumni Health Study | Regulara | Highly active (≥2500 kcal/wk) vs. Inactive (<1000 kcal/wk) | Colon: 280 | Questionnaire and death certificates | Age, BMI and parental history of CRC | BMI | Self-administered questionnaire | |
 Lee, I., 1997 [42] | 40–84 | USA | Physician’s Health Study | Regulara | 1+ times/week vs. <1 time/week | Colon: 217 | Pathology reports in medical records | Age, alcohol consumption and treatment assignment | BMI | Self-administered questionnaire | |
 Lee, K., 2007 [43] | 40–69 | Japan | Japan Public Health Center-Based Prospective Study (JPHC) | Regulara,b | >43.75 MET-h/day vs. <28.25 MET-h/day | Colorectal: 486 | Population-based cancer registries and death certificates, 94.7% verified by histological exam | Age, study area, FHCRC, smoking, alcohol intake, intake of red mean, dietary fiber and folate | BMI | Self-administered questionnaire | |
 Morikawa, 2013 [45] | 30–75 | USA | Health Professionals Follow-up Study (HPFS) and the Nurses’ Health Study (NHS) | Regular (mean of all past 2-year measures) | ≥9 MET-h/wk. vs. <9 MET-h/wk. | Colorectal: 861 | Medical records and pathology reports | Alcohol, folate, vitamin D, calcium, caloric and red meat intake, current smoking status, smoking before 30 years of age, current multivitamin use, current aspirin use, previous sigmoidoscopy, and family history of colorectal cancer | BMI | Self-administered questionnaire | |
 Schmid, 2016 [46] | 50–71 | USA | National Institutes of Health AARP Diet and Health Study (NIH-AARP Diet and Health Study) | Past 10 yearsb | >7 h/wk. MVPA vs. None | Colon: 4151 | Cancer registry records. Self-reports and confirmation through medical records used to ascertain completeness of reporting (~90%) | Age, sex, race/ethnicity, education, smoking status, family history of colon cancer, hormone replacement therapy use (women only), nonsteroidal anti-inflammatory drug use, total fiber intake, red meat intake and alcohol consumption | BMI | Self-administered questionnaire | |
 Thune, 1996 [44] | 20–49 | Norway | Population-based Cohort of Norway | Past year | Active vs. sedentary | Colon: 335 | Cancer Registry of Norway, 95% verified by histological exam | Age at entry, geographic region | BMI | Self-administered questionnaire with clinical examination for inconsistency | |