Background: Researchers interested in the effect of health on various life outcomes often use self-reported health and disease as an indicator of true, underlying health status. However, the validity of reporting is questionable as it relies on the awareness, recall bias and social desirability. Accordingly, the measured biomarker is generally regarded as a more precise indication of the disease.
Objectives: The study aimed to examine the discrepancy between the reporting and biomarkers of hypertension and diabetes in the contemporary China, and explore sociodemographic characteristics that are correlated with misreporting.
Methods: Using data from the third wave of China Health and Retirement Longitudinal Study (CHARLS), we selected individuals aged 40-85 years old who participated in both a health interview survey and a biomarker examination. Sensitivity, specificity, false negative reporting and false positive reporting were used as measurements of (dis)agreements or (in)validity. Binary and multinomial logistic regression were used to estimate under-report or over-report of hypertension and diabetes.
Results: Self-reported hypertension and diabetes showed low sensitivity (71.98% and 49.21%, respectively) but high specificity (93.71% and 98.05%, respectively). False positive reporting of hypertension and diabetes were 3.85% and 1.67%, while false negative reports were extremely high at 10.85% and 7.38%. Education degree, hukou, age and gender affected both the specific error and the overall error of reporting hypertension and diabetes, but there were some differences in the magnitude and direction.
Conclusion: Self-reported conditions underestimate the disease burden of hypertension and diabetes. Adding objective measurements into social survey could improve data accuracy allowing better understanding of socioeconomic inequalities in health, especially collecting biological indicators for populations with limited access to regular healthcare in China. Furthermore, there is an urgent need to provide basic health education and physical examination to citizens, to facilitate access to healthcare and make focused interventions to lower the incidence and unawareness of disease in China.