Validity of self-reported hypertension in Mashhad population: brief report

Background: Researchers and health specialists are increasingly obtaining information on chronic illnesses from self-reports. This study validates self-reports of hypertension, based on a recently fielded survey in Mashhad City, Iran. Methods: In this cross-sectional study, we used the results of 2015 census in Mashhad City, a population based survey of people over the age of 30 (n=300745) to determine the proportion of self-reported hypertension. In this study, the data of the studied population was extracted from the databank of Sina Electronic Health Record System (SinaEHR®) and patients with ICD10 codes including I10 and I11 approved by doctors as a reference. Finally using SPSS software, version 20 (SPSS Inc., Chicago, IL, USA) and MedCalc (https://www.medcalc.org/calc/odds_ratio.php), sensitivity, specificity, positive predictive value, negative predictive value were calculated with 95% confidence interval. Results: Sensitivity of self-reported hypertension was 23.92% (CI95%: 23.43-24.41), specificity 97.03% (CI95%: 96.97-97.09), Positive Linkelihood Ratio 8.06% (CI95%: 7.82-8.30), Negative Linkelihood Ratio 0.78% (CI95%: 0.78-0.79), Positive Predictive Value 46.34% (CI95%: 45.60-47.08), Negative Predictive Value 92.25% (CI95%: 92.20-92.29). The self-reported sensitivity to hypertension in males, Iranian individuals, single, aged 60 and over, body mass index lower 18.5 individual with university education was higher, which was 24.67%, 31.09%, 30.07%, 32.43% and 26.03% respectively. Conclusion: Although the sensitivity of self-reported hypertension was poor in this study, but specificity and positive and negative predictive values were fairly good.