Purpose:
To evaluate the psychometric properties of the Compliance with Annual Diabetic Eye Exams Survey (CADEES), a new instrument designed to identify the factors related to adherence with yearly eye exams. While diabetic retinopathy is the leading cause of blindness in adults aged 20-74, early diagnosis and treatment can reduce the likelihood of vision loss by 90%. Unfortunately, fewer than 50% of those diagnosed with diabetes receive annual eye exams.
Methods:
The 45-item survey was developed using the framework of the Health Belief Model (HBM). The survey measured health beliefs, demographics, and eye exam history. Participants rated the extent to which they agreed with each health belief statement using a Likert scale.
Results:
Participants (n=127) were 47% male and ranged in age from 24 to 83 years (M=56.3, SD=12.1). Reliability analyses on items created to measure specific HBM constructs showed acceptable Cronbach’s alphas (>.70) for two of the six constructs (seriousness and barriers). A principal components analysis supported the presence of four distinct factors, comprising 37% of the variance. Three of the four factors were identifiable within the constructs of the HBM (seriousness, susceptibility, and barriers); however, factor scores did not predict adherence. Based on univariate results comparing those who had an eye exam in the past year with those who had not, 15 health belief items were identified as potential predictors for adherence. A logistic regression model containing these items classified cases with 78% accuracy (Nagelkerke R-Square = .338). The strongest predictors were beliefs about whether diabetic eye disease can be seen with an eye exam (p=.01) and whether insurance covered most of the eye exam cost (p<.01). A logistic regression model containing demographic variables (age, sex, race, insurance status, hemoglobin A1c, and years diagnosed with diabetes) showed that adherence was associated with a longer duration of diabetes (p=.02) and lower hemoglobin A1c levels (p=.01).
Conclusions:
Further research is needed to confirm these preliminary results, and to determine whether the Health Belief Model is the best framework to use when attempting to predict compliance with annual eye exams.
Keywords: diabetes • diabetic retinopathy