Table 1 Variable declaration

severe CRF

Y

Score: ≤30 = 0, 31–60 = 1 (severe CRF)

Age

X₁

Years: ≤45 = 0, 46–55 = 1, > 55 = 2

Marital status

X₂

Unmarried = 0, Married = 1

Education level

X₃

Primary school and below = 0, Junior high school = 1, High school = 2, College/university or above = 3

Occupation

X₄

Retired personnel = 0, State and public institutions = 1, Staff and workers of enterprise = 2, Self-employed personnel = 3, Unemployed person = 4

Per capita monthly income

X₅

CNY: ≤2000 = 0, 2001–4000 = 1, 4001–5000 = 2, > 5000 = 3

Place of residence

X₆

City = 0, Countryside = 1

Long-term passive smoking

X₇

Expose to the smoke environment caused by smokers at least 4 times a week, for more than 15 min per day, and persist for a long time: No = 0, Yes = 1

BMI

X₈

17\( \sim \)24 = 1, > 24 = 2

Physical exercise

X₉

At least 30 min each time: Never = 0, Once/week = 1, ≥ 2–3 times/week = 2

Breakfast

X₁₀

Never = 0, Occasionally = 1, Often = 2

Coffee consumption

X₁₁

Never/Occasionally = 0, Often/Daily = 1

Menopause

X₁₂

No = 0, Yes = 1

Diagnostic type

X₁₃

New diagnosis = 0, Recrudescence = 1

Lymph node metastasis

X₁₄

No = 0, Yes = 1

Cancer stage

X₁₅

I=0, II=1, III+IV=2

HPV infection

X₁₆

No = 0, Yes = 1, Not checked = 2

Uncertainty of Illness

X₁₇

Score: 25\( \sim \)58 = 0 (Low), 59\( \sim \)125 = 1 (Medium/High)

Coping Styles

X₁₈

Propensity to score: Face = 0, Avoid = 1, Yield = 2

Perceived Social Support

X₁₉

Score: 12\( \sim \)36 = 0 (Low), 37\( \sim \)60 (Medium) = 1, 61\( \sim \)84 (High) = 2

Sense of Coherence

X₂₀

Score: 13\( \sim \)63 (Low) = 0, 64\( \sim \)91 (Medium/High) = 1