in the study. In addition, prospective participants or parents/guardians completed an eligibility and health questionnaire. Prospective participants who signed the initial paperwork were assigned a screening number.
Prospective participants acclimated to ambient temperature and humidity conditions for at least 15 minutes prior to participating in clinical procedures. During the study, applicable waiting/instrumentation rooms were maintained at a temperature of 68oF to 75oF and relative humidity from 35% to 65%.
Application of Moisturizers
Participants were distributed pre-weighed units of the test material and instructed to apply it to each leg according to the following instructions:
- Apply a sufficient amount of moisturizer (about the size of a half-dollar coin) to the appropriate leg (starting at the kneecap and down to the ankle) once daily in the evening for 10 days. Please make sure the moisturizer covers the entire lower leg area. Wash and dry hands between applications of each test material (one moisturizer per leg) to avoid cross-contamination of the sites.
Regression Period
After completion of the day 10 procedure, participants were instructed not to shave their legs, apply any moisturizing products, or use cleansers with moisturizing effects on the legs for a 5-day regression period during which no moisturizer was used.
Statistical Analysis
Corneometer Measurements
At baseline, day 10, and day 15, triplicate corneometer (CM 825, Courage & Khazaka, Germany) measurements were taken on both legs of each participant at the midline between the knee and ankle of the lateral side.
Statistical Analysis
Triplicate corneometer measurements for each participant, location, and time point were averaged prior to statistical analysis. All results are presented as the percent mean change from baseline. Significance of mean change from baseline and comparison between groups was tested using a paired t-test. All statistical tests were 2-sided at a significant level of alpha=0.05. P-values were reported to 3 decimal places. No multiple testing corrections were considered in the study. Statistical analyses were performed using SAS software version 9.40 series (SAS Statistical Institute).
RESULTS
Ceramide Plus NMF Cream vs Ceramide Cream
Assessment of skin hydration by corneometer was performed on day 10 after once daily use of ceramide plus NMF or ceramide cream, and a 5-day regression period of no daily moisturization (day 15). Daily moisturization for 10 days with the ceramide plus NMF cream resulted in a 76.9% increase in corneometer units compared to baseline (P<0.001), while daily moisturization of the ceramide cream resulted in an increase of 50.1% compared to baseline (P<0.001), with an overall statistical significance in favor of the ceramide plus NMF cream vs the ceramide cream (P<0.001) (Figure 1).
