Abstract
BACKGROUND: Research based in primary care suggests that hearing loss may be underreported as well as inconsistently recorded in patient histories. In this study, we aimed to develop and validate a case definition for hearing loss among older adults in primary care, using electronic medical records. METHODS: We used data from adult patients aged 55 years and older from 13 practices in the Southern Alberta Primary Care Research Network database, part of the Canadian Primary Care Sentinel Surveillance Network (CPCSSN), from Dec. 1, 2014, to Dec. 31, 2016. We developed a hearing loss case definition that was translated into an electronic algorithm. A record review was undertaken as the reference standard, followed by application of the algorithm to the sample. Validation metrics included sensitivity, specificity, positive predictive value and negative predictive value, as well as prevalence. We assessed risk factors using the Fisher exact test and odds ratios. RESULTS: The sample included 1000 patients; 496 (49.6%) were female and the mean age was 67.5 (standard deviation 9.6) years. Sensitivity of the case definition algorithm was determined to be 87.3% (95% confidence interval [CI] 76.5%-94.4%) with specificity valued at 94.8% (95% CI 93.1%-96.1%). Positive and negative predictive values were 52.9% (95% CI 42.8%-62.8%) and 99.1% (95% CI 98.2%-99.6%), respectively. The prevalence of hearing loss within the sample was 6.3% (95% CI 4.9%-7.9%). Older age was a significant risk factor for hearing loss (t = 4.98, 95% CI 3.76-8.65). Men had greater odds of hearing loss than women (odds ratio 1.65, 95% CI 0.98-2.79). INTERPRETATION: The validated case definition for hearing loss in community-based older adults had high sensitivity and specificity. It may be applied to surveillance and future epidemiologic research within the CPCSSN database.