Objective: To examine patients' perceptions on the relative importance of the physical characteristics and appearance of dietary supplements, and to evaluate two supplements with the same combination of vitamins and minerals used in the Age-Related Eye Disease Study (AREDS) with respect to ease of swallowing and other features in elderly patients.
Design: A single-site, single-visit, crossover design, subject-masked comparison of two dietary supplements (ICaps AREDS Formula--Alcon; Ocuvite PreserVision-Bausch & Lomb).
Setting: Ophthalmology practice.
Patients: 50 patients aged 50 years or older.
Interventions: Patients ranked the importance of eight physical characteristics of a vitamin tablet or capsule (ease of swallowing, size, shape, color, smell, coating, texture, and taste) irrespective of the test products used in the study and then took both test products randomly and were asked to indicate which product they preferred based on the same eight characteristics.
Main outcome measures: Overall patient preference and preference for swallowing two tablets at once.
Results: The highest rated (most important) characteristic in a vitamin supplement was ease of swallowing, with a median score of 9.0 on a 0-10 visual analogue scale. The characteristic of least importance was tablet color, with the lowest median score of 1.0. Statistically significant differences were detected between the products with regard to preferences for ease of swallowing, swallowing two tablets at once, size, and coating (P < or = .0001). Significantly more patients preferred the ICaps AREDS formula to Ocuvite PreserVision with respect to these characteristics and overall preference (P < .001). Age, gender, and previous vitamin use were contributing factors in the rating of physical characteristics and tablet preferences.
Conclusion: Based on the results of this study, ease of swallowing is the most important characteristic of dietary supplement tablets for elderly patients, followed by taste, size, and smell. Significant differences in preference exist between the study products, which contain similar formulations but have different physical characteristics.