Food Frequency Questionnaire (FFQ) for Coronary Heart Disease (CHD) Patients

Evaluation of the Psychometric Properties of a Food Frequency Questionnaire Developed for Patients With Coronary Heart Disease in Northern China

This study aims to evaluate the psychometric properties of a newly developed FFQ specified for northern Chinese CHD and their high risk patients (CHD-FFQ). The psychometric properties include test-retest reliability, content validity, convergent validity, discriminant validity, concurrent validity and predictive validity. Particularly, this study will measure the physiological indicators, including plasma lipid profile (i.e. TG, TC, HDL-C, LDL-C), BG, BP and BMI twice at baseline and the end. The level of these physiological indicators will be compared with the fat intake measured by the CHD-FFQ, i.e. the baseline intake to test its convergent validity. It is also expected to predict the diet-related progression of CHD risks among high-risk individuals, i.e. patients with two or more CHD risk factors as following: raised fasting blood glucose (BG) level, increased blood pressure (BP), increased triglycerides (TG), decreased HDL-Cholesterol (HDL-C), increased LDL-Cholesterol (LDL-C), smoking and central obesity (International Diabetes Federation, 2015). In addition, this study will provide the FFQ's concurrent validity in assessing the intake of energy and nutrients against the CDC-FFQ. Moreover, whether the FFQ could detect the known differences in energy intake between men and women will be established for its discriminant validity.

Inclusion Criteria:

• 18 years or older;

• Have no CHD at enrollment;

• At high risk of CHD with at least two of the following risk factors:

  • current smoking: current smokers are defined as individuals who smoked regularly during the last 12 months
  • central obesity: for Chinese, central obesity is defined as waist circumstance above 90cm for male and 80cm for female, or with BMI above 30kg/m²
  • raised BP (systolic BP [SBP] ≥ 130 mmHg or diastolic BP [DBP] ≥85 mmHg or under antihypertensive treatment)
  • raised fasting BG (FBG) (100mg/dL [5.6mmol/L]) or under treatment with insulin or oral hypoglycemic agents
  • elevated TG (150mg/dL [1.7mmol/L])
  • elevated TC (≥ 240 mg/dL [5.18 mmol/L])
  • raised LDL-C (≥ 160 mg/dL [4.15 mmol/L])
  • decreased HDL-C (<40 mg/dL [1.03 mmol/L] for males, and <50 mg/dL [1.29 mmol/L] for females)
  • undergoing hyperlipidemia treatment

Exclusion Criteria:

• Impaired bilateral hearing
• Impaired mental status (according to their medical record)