Table 4.
The score range, mean as well as floor and ceiling effects and skewness of each item in the final version of the Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS), as scored by the participating women (n = 71).
| VAS-IBS | Score Range* | Mean (SD) | Floor effects % | Ceiling effects % | Skewness |
| Physical symptoms | |||||
| Abdominal Pain | 0–100 | 46.5 (29.4) | 4.2 | 7.0 | 0.444 |
| Diarrhoea | 0–100 | 60.0 (34.3) | 7.1 | 20.0 | -0.283 |
| Constipation | 0–100 | 58.8 (32.9) | 2.8 | 12.7 | -0.226 |
| Bloating and Flatulence | 0–100 | 33.3 (27.1) | 8.5 | 1.4 | 0.774 |
| Vomiting and Nausea | 0–100 | 66.1 (33.8) | 4.2 | 25.4 | -0.543 |
| Mental health | |||||
| Perception of mental well-being | 0–100 | 53.2 (30.0) | 5.5 | 5.6 | -0.044 |
| Quality of Life | |||||
| Influence daily life ** | 0–80 | 43.6 (29.2) | 18.8 | 0 | -0.297 |
The limit of the floor and ceiling effect was set at 20% or less and the skewness should be between -1 and +1 to be acceptable. 0 = worst symptom/health and 100 = best symptom/health
** n = 16