TABLE 3.
Subscales (Factor Structure) of the Inflammatory Bowel Disease Symptom Inventory Long Form
| Subscale | Item | Item retained in short form (item # in short form) |
r corr | r | I | II | III | IV | V | E |
|---|---|---|---|---|---|---|---|---|---|---|
| I. Bowel Symptoms | 0.65 | 0.84 | 0.58 | 0.58 | 0.34 | 0.30 | ||||
| 3. On average, the number of bowel movements I had each day was… | Yes (i3) | 0.53 | 0.63 | 0.77 | ||||||
| 4. The number of loose/liquid bowel movements or diarrhea I had most days was… | Yes (i4) | 0.62 | 0.71 | 0.71 | ||||||
| 5. My stool consistency was generally… (administered but not scored in long form) | Yes (i5) (scored in short form only) | |||||||||
| 6. I noticed blood in my stool | Yes (i6) | 0.38 | 0.43 | 0.90 | ||||||
| 13. Losing control of bowel movements | Yes (i14) | 0.63 | 0.81 | 0.59 | ||||||
| 15. Waking because of urge to have bowel movements | Yes (i16) | 0.61 | 0.68 | 0.73 | ||||||
| 17. Urgency of bowel movements | Yes (i18) | 0.68 | 0.78 | 0.63 | ||||||
| 20. Urge for bowel movement despite empty bowels | No | 0.65 | 0.74 | 0.68 | ||||||
| 22. Soiling underwear | Yes (i21) | 0.58 | 0.75 | 0.66 | ||||||
| 26. Fever over 37.8°C or 100°F | No | 0.54 | 0.55 | 0.84 | ||||||
| II. Abdominal Discomfort | 0.72 | 0.87 | 0.72 | 0.29 | 0.40 | |||||
| 2. I had abdominal pain | Yes (i2) | 0.70 | 0.88 | 0.48 | ||||||
| 7. I had loss of appetite | Yes (i7) | 0.63 | 0.66 | 0.75 | ||||||
| 8. I had nausea | Yes (i8) | 0.44 | 0.50 | 0.87 | ||||||
| 9. I had vomiting | Yes (i9) | — | — | — | ||||||
| 10. I had tenderness in my abdomen when touched | Yes (i10) | 0.68 | 0.83 | 0.55 | ||||||
| 12. Excessive bowel gas (farting) | Yes (i13) | 0.40 | 0.35 | 0.94 | ||||||
| 14. Abdominal bloating | Yes (i15) | 0.63 | 0.64 | 0.77 | ||||||
| 16. Waking because of abdominal pain | Yes (i17) | 0.64 | 0.74 | 0.67 | ||||||
| 19. Difficulty releasing gas | Yes (i20) | 0.60 | 0.54 | 0.84 | ||||||
| 23. Abdominal cramps | Yes (i22) | 0.73 | 0.90 | 0.43 | ||||||
| 27. In the past week, I had a lump in my abdomen | Yes (i11b) | 0.28 | 0.37 | 0.93 | ||||||
| III. Fatigue | 0.73 | 0.86 | 0.28 | 0.41 | ||||||
| 1. My health was… | Yes (i1) | 0.73 | 0.70 | 0.72 | ||||||
| 11. Feeling fatigued or tired and worn out | Yes (i12) | 0.64 | 0.90 | 0.44 | ||||||
| 18. Finding it hard to get things done | Yes (i19) | 0.71 | 0.82 | 0.58 | ||||||
| 21. Feeling generally unwell | No | 0.75 | 0.75 | 0.66 | ||||||
| 24. Having low energy | No | 0.66 | 0.92 | 0.39 | ||||||
| 25. Having trouble maintaining or gaining weight | No | 0.44 | 0.44 | 0.90 | ||||||
| IV. Bowel Complications | 0.31 | 0.47 | 0.33 | |||||||
| 33. Anal fissure (a tear around the anus) | No | 0.34 | 0.49 | 0.87 | ||||||
| 34. Abscess (a localized collection of pus surrounded by inflamed or infected tissue–inside the body or on the skin) | No | 0.29 | 0.77 | 0.64 | ||||||
| 35a. Do you have a fistula? (a fistula is any internal or external path from the bowel to other organs or to the outside skin)… 35c. Has the fistula been active (sore, swollen, or draining) during the past week? | Yes (scored with Bowel Symptoms) (i24a,b) | 0.18 | 0.59 | 0.81 | ||||||
| 35d. Is this a new fistula you have developed in the past week? (not scored) | No | |||||||||
| V. Systemic Complications | 0.43 | 0.54 | ||||||||
| 28. Joint pain (arthralgia/arthritis) | Yes (scored with Abdominal Discomfort factor) (i23) | 0.43 | 0.57 | 0.82 | ||||||
| 29. Inflammation of the coloured part of the eyes (uveitis/iritis) | No | 0.23 | 0.44 | 0.90 | ||||||
| 30. Tender red lumps on shins or arms (erythema nodosum) | No | 0.24 | 0.44 | 0.90 | ||||||
| 31. Small painful sores or ulcerations on the skin (apthous ulcers/apthous stomatitis) | No | 0.26 | 0.37 | 0.93 | ||||||
| 32. Painful sores or ulcerations on the skin (pyoderma gangrenosum) | No | 0.19 | 0.47 | 0.88 |
Note. N = 235. rcorr, corrected (jack-knife) item-total correlations or factor correlations with the total score. All factor loadings from the confirmatory factor analysis of the IBDSI-LF are significant at P < 0.05. r, zero-order Pearson correlations; subscale intercorrelations are also zero-order Pearson r’s . All correlations are significant at P < 0.001. E, standardized error variance (unique item variance not explained by common factors).