Table 1.
Characteristics of included studies
| Studies | OR | Study period | Region | Study design | Age (years) | Sex | Participants | Cancer | Statistical analysis | Adjustments | NOS score |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Milán et al. [9] | 1.1 | 1976–1999 | Finland | Cohort study | ≥ 18 | Male and female | 666 | BCC | Conditional logistic regression analysis | NA | 8 |
| Ming et al. [10] | 0.85 | 1998–2001 | USA | Case–control study | 66.4 versus 60.1* | Male: 51.3% versus 39.9% | 4591 | NMSC | Multivariable logistic regression | Age, sex, topical steroid use, and ethnicity | 7 |
| Hagströmer et al. [7] | 1.5 | 1965–1999 | Sweden | Cohort study | 15.7* | Male and female | 15,666 | NMSC, melanoma | χ2 test | NA | 7 |
| Olesen et al. [26] | 2.4 | 1977–1996 | Denmark | Cohort study | NA | Male and female | 6275 | NMSC | Poisson regression methods | NA | 7 |
| Synnerstad et al. [27] | 0.49 | 1986–2004 | Sweden | Cohort study | 2.6 (5.5) to 39.3 (10.9)* | Male and female | 6280 | Melanoma | Poisson regression analysis | Age group, sex, and year | 8 |
| Arana et al. [28] | 1.74 | 1992–2006 | UK | Retrospective cohort study | All ages | Male and female | 4,518,131 | Melanoma, NMSC | Mantel–Haenszel | Age and sex | 7 |
| El-Zein et al. [11] | 0.64 | 1979–1985 | Canadian | Case–control study | 35–70 | Males | 3809 | Melanoma | Logistic regression | Age, income, respondent status, ancestry, and sports and/or outdoor activities | 6 |
| Janković et al. [12] | 4.17 | 2006–2007 | Montenegro | Case–control study | NA | Female | 200 | BCC | Multivariate logistic regression analysis | Age, sex, and marital status | 7 |
| Dyer et al. [13] | 1.54 | NA | USA | Cohort study | Median age 72 | Female 34 (3%) versus male 1097 (97%) | 1131 | BCC | Multiple logistic regression | Sex, age, education, basal cell carcinomas in prior 5 years, squamous cell carcinomas in prior 5 years, actinic keratoses at baseline, family history of skin cancer, current or former smoker | 8 |
| Jensen et al. [6] | 0.59 | 1977–2006 | Denmark | Cohort study | NA | Male and female | 31,330 | Melanoma, BCC, SCC | Byar’s approximation | NA | 8 |
| Hajdarbegovic et al. [14] | 1.05 | 2000–2010 | Netherlands | Case–control study | 57 ± 14 versus 56 ± 14* | Male and female | 353 | Melanoma | Logistic multiple regression analysis | Unadjusted OR | 7 |
| Cheng et al. [15] | 1.83 | NA | USA | Case–control study | 25–74 | Female | 1312 | SCC | Multiple logistic regression | Age, gender, and skin reaction to the first hour of sunlight during summer (blister, painful sunburn followed by peeling, mild sunburn followed by tanning, tanning with no sunburn) | 8 |
| 1.52 | NA | USA | Case–control study | 25–74 | Female | NA | BCC | Multiple logistic regression | Age, gender, and skin reaction to the first hour of sunlight during summer (blister, painful sunburn followed by peeling, mild sunburn followed by tanning, tanning with no sunburn) | 8 | |
| Marasigan et al. [16] | 0.46 | NA | Belgium | Case–control study | 57.4* for controls, 52.2* for cases | Male and female | 232 | Melanoma | Conditional logistic regression | Age, sex, sunburn sensitivity, hair color, number of moles, sunburn as juvenile, ever sunbed use, familial melanoma | 8 |
| Cho et al. [8] | 1.75 | 1996–2010 | USA | Case–control study | 69.6 (13.5) versus 69.5 (13.5)* | Female | 1179 | SCC | Logistic regression analysis | Race, smoking history, ionizing radiation exposure, corticosteroid and cyclosporine use, non-SCC skin cancers, odds ratio for SCC development | 9 |
| D'Arcy et al. [17] | 1.07 | 1992–2013 | USA | Case–control study | 66–99 | Female | 1,844,575 | Melanoma | Logistic regression analysis | Sex, age, race, calendar year of selection, and measures of socioeconomic status and healthcare utilization | 7 |
| Mansfield et al. [31] | 0.96 | 1998–2016 | UK | Cohort study | 41.1 [24.9–60.7] versus 39.8 [25.9–58.4]# | Female | 2,711,745 | Melanoma | Cox proportional hazards regression model | Sex, primary care practice, date, and age | 8 |
| 1.1 | 1998–2016 | UK | Cohort study | 41.1 [24.9–60.7] versus 39.8 [25.9–58.4]# | Female | NA | NMSC | Cox proportional hazards regression model | Sex, primary care practice, date, and age | 8 | |
| 0.64 | 1982–2016 | Denmark | Cohort study | 13.7 [1.7–21.1] versus 13.5 [1.7–20.8]# | Female | 490,618 | Melanoma | Cox proportional hazards regression model | Sex, date, and age | 8 | |
| 1.17 | 1982–2016 | Denmark | Cohort study | 13.7 [1.7–21.1] versus 13.5 [1.7–20.8]# | Female | NA | NMSC | Cox proportional hazards regression model | Sex, date, and age | 8 |
*Mean (SD); #median [IQR]