Dietary Intake is assessed using a 36 item measure developed by Resnicow and colleagues and validated in a large sample of African American adults [35]. Participants are asked to indicate the number of times that they ate each item in the last seven days and the amount of food (1/2 cup, 1 cup). Portion size is fixed to that of a medium serving.
Medication Adherence to prescribed antihypertensive medications is assessed with the widely used and well-validated 8-item scale developed by Morisky [36,37]. The measure has acceptable reliability in the development sample (α = 0.83), and correlated well with the previously validated 4-item version [36] (r = 0.64, p < .05). The measure was found to be able to correctly categorize BP control status in 80% of cases [37]. Data on medication adherence will allow us to assess the potential effect of adherence on BP control.
Comorbid Medical Conditions are assessed with the Charlson Comorbidity Index (CCI) [38], in order to adjust for the confounding effects of comorbidity on BP and their non-uniform prognostic impact. The CCI is a weighted index for prospectively classifying comorbid conditions, which takes into account the number and seriousness of comorbid diseases.