K.W.TAN1, K.J.LEW1, P.S.S.LEE1, S.K.ONG1, H.L.KOH1, E.S.LEE1
Studies of concordance comparing patients’ self-reports of diseases with a criterion standard (e.g. medical records) have been used to evaluate validity of self-reported data in public health research, and to assess patients’ health literacy and patient-physician communication. Such studies were lacking in Singapore primary care, even for highly prevalent conditions like diabetes. The aims of this study were to evaluate concordance between patients’ self-reports of diabetes and their medical records of diabetes diagnosis, and to identify factors associated with concordance.
A cross-sectional, interviewer-administered survey on diabetes was conducted amongst patients with chronic diseases at Toa Payoh Polyclinic, after obtaining written consent to assess their medical records. Interviewers were blinded to participants’ chronic conditions. Concordance was evaluated using Cohen’s Kappa (κ) with level of significance of p<0.05. A logistic regression model was used to find factors associated with concordance.
478 patients were recruited. There was substantial agreement between self-reported diabetes and medical records of diabetes diagnosis (κ=0.762, 95% CI: 0.674-0.849, p<0.001). Logistic regression model suggested that non-Chinese patients had greater odds of concordance than Chinese patients (OR=4.1, 95% CI 1.38-17.76, p=0.03). Participants with three or more chronic diseases (multimorbidity) were associated with poorer concordance (OR=0.21, 95% CI 0.09-0.46, p<0.001).
The findings support the use of self-reports of diabetes by patients with chronic diseases in the primary care setting for future research. We propose to conduct further studies to explore the health literacy and patient-physician communication for patients with multimorbidity and of Chinese ethnicity to explain the study findings.