Table 2.
Quality of symptom and symptom-medication scores.
| Quality index | Rhinoconjunctivitis Total Symptom Score, mean (95% CI) | Visual Analogue Scale, mean (95% CI) | Combined Symptom and Medication Score, mean (95% CI) |
| Intravariation indexa | 5.1 (4.5-5.6) | 6.1 (5.5-6.7) | 2.9 (2.6-3.2) |
| % of zero valuesb | 38.9 (33.3-44.5) | 43.3 (37.2-49.3) | 20.4 (16.0-24.8) |
| Coefficient of variationc | 134.8 (116.5-153.0) | 138.1 (115.8-160.5) | 86.3 (72.3-100.3) |
| % of changes in trendsd | 31.3 (28.2-34.4) | 28.9 (25.6-32.3) | 32.7 (29.6-35.7) |
aAverage of intravariation index by subjects; for each ith subject, (1) the percentage of the number of variations between 2 consecutive days is calculated, 
, where t= 1,,,,,,, T is the indicator of time point considered, y is the value of the symptom medication score considered, and I is a binary variable, which is 1 when the condition in the brackets is verified, 0 otherwise; (2) the individual variation range has been calculated (rVAR = (max(y1, …,yT) – min(y1, …, yT)) + 1/S, where S represents the unit increase for each symptom medication score, that is, S=1 for Visual Analogue Scale and Rhinoconjunctivitis Total Symptom Score and S=0.167 for Combined Symptom and Medication Score); and (3) the average of all individual intravariation index values was calculated, 
, for each symptom score or symptom medication score.
b100*number of zero compiled values/actual compiled days.
cAverage of individual coefficient of variation (100*SD/mean).
dNumber of changes in trends (plus/minus/stable) within ith differences between 2 consecutive values of symptom medication score.