Table 4 Measurement properties of the included instruments
| Â | Internal consistency | Test-retest reliability | Interviews/focus groups | Pilot test | Convergent/divergent | Discriminant validity | Measurement error | Criterion validity | Responsiveness |
|---|---|---|---|---|---|---|---|---|---|
For paediatrics | |||||||||
 IMPACT | 0.96 | ICC: 0.90 | (1) Interview with 82 patients (2) Based on IBDQ (3) Item generation, reduction, and selection procedure | Pilot study, wording of question | Correlation with (1) Current disease activity: −0.54 (2) Colitis symptom score: −0.40 (3) PCDAI: −0.63 (4) Disease activity pattern: −0.43 | Higher scores for the patients with quiescent disease (P < 0.005) | Test-retest coefficients were calculated. | Correlation with (1) Piers-Harris Happy domain: 0.61 (2) CHQ-87: 0.67 | NA |
 IMPACT-II | 0.57 to 0.86 | ICC: 0.67 to 0.91 | Based on IMPACT | Pilot studies | NA | Higher scores in the patient with severe, moderate symptoms (P < 0.05) | Test-retest coefficients were calculated. | Correlations with Tacqol (1) Item: 0.44 to 0.63 (2) Domain: 0.46 to 0.72 | NA |
 IMPACT-III | (1) Factor analysis conducted; (2) 0.74 to 0.88 | ICC: 0.66 to 0.84 | Based on IMPACT | Pilot study (20 patients) | Paper and computer versions were comparable | Lower scores in the patient with severe, moderate symptom (P < 0.05) | Test-retest coefficients were calculated. | Correlations with domain of CHQ-87: 0.47 to 0.72 | NA |
For adults | |||||||||
 IBDQ-32 | 0.70 | ICC: 0.90 to 0.99 | (1) Interview with 97 patients (2) The most frequent and important items | NA | Correlated with CDAI (r = −0.67) | Lower scores in patients who required surgery (P < 0.05) | Standard deviations of the score changes were of similar magnitude | Correlation of changes in IBDQ and other measures were similar (P < 0.05) | Sensitivity to change for the improved or deteriorated patients (P < 0.05) |
 SIBDQ | (1) 0.78 (2) 92% and 90% of the variance in CD and UC were explained | r: 0.65 | Based on IBDQ-32 | NA | Correlation with (1) SCCAI: −0.42 to −0.85 (2) Seo index: −0.41 to −0.64 | Lower scores in the patients with moderate-severe relapse (P < 0.05) | Those with unchanged disease status showed no significant difference. | Correlation with the IBDQ-32 (P < 0.05) | (1) Sensitivity to change (P < 0.05) (2) decreased by −0.93 for the relapsed patients |
 IBDQ-36 | NA | NA | Based on interviewer-administered measure | NA | NA | Lower score for IBD patients than the control (P < 0.05) | NA | NA | NA |
 IBDQ-9 | (1) Rasch analysis conducted; (2) UC: 0.95; CD: 0.91 | (1) r: 0.76 for UC, 0.86 for CD (2) ICC: 0.82 for UC, 0.84 for CD | Based on IBDQ-36 | Pilot test | (1) Item-total correlation: 0.59 to 0.85 (2) Correlation with clinical indices of activity: UC (r = 0.70) and CD (r = 0.70) | Lower scores in the patients with moderate-severe relapse (P < 0.01) | Scores of the first and second questionnaires correlated significantly | Correlation with IBDQ-36: 0.91 | (1) Sensitivity to change (P < 0.01) (2) effect size: UC = −2.67, CD = −5.29 |
 RFIPC | (1) Factor analysis conducted; (2) 0.79 to 0.91 | (1) r* (instrument): 0.87 (2) r (item): 0.47 to 0.79 | (1) 45-min interview (2) items expressed by IBD patients | Add 3 items using pilot study | Associated with greater disease severity, female gender, and lower educational status. | Worse scores for the patients with lower educational status, greater disease severity, female patients and UC patients (P < 0.05) | Test-retest coefficients were calculated. | Associated with SCL-90 (P < 0.05) | NA |
 CCQIBD | NA | r: 0.75 to 0.95 | (1) Based on other instruments (2) Review of the literature and professional experience | NA | NA | Lower scores for Crohn’s surgical patients (P < 0.05) | NA | Associated with sickness impact profile (P < 0.05) | NA |
 PIBDQL | NA | NA | Comprehensive definition of the patients’ health | NA | PIBDQL scores had relationship with daily stools and CDAI score (P < 0.05) | (1) Higher scores for the surgical patients (P < 0.05) (2) Lower scores for patients than healthy people (P < 0.05) | NA | NA | NA |
 CGQL | 0.866 | NA | Structured interview | NA | NA | Lower scores in the patients with 0 ~ 5 years after surgery (P < 0.05) | NA | Correlation with SF-36: 0.31 to 0.74 (P < 0.05) | Sensitivity to change (P < 0.001) |
 SHS | NA | r: 0.71 to 0.91 | Theoretic model was presented. | NA | Correlation with PGWB: −0.51 to −0.78 | Higher scores for the patients in relapse (P < 0.001) | Test-retest coefficients were calculated. | Correlation with (1) IBDQ: −0.41 to −0.78 (2) RFIPC: 0.50 to 0.78 | Change in SHS was related with change in disease activity P < 0.05) |
 EIBDQ | (1) Factor analysis conducted (2) Variance extracted: 63% (3) 0.55 to 0.86 | NA | Comprehensive review of the IBD literature | Pilot study | Correlation with CDAI (1) CD: 0.52 (2) UC: 0.30 | NA | NA | Correlation with SF-36 (1) CD: 0.48 (2) UC: 0.32 | NA |
 CLIQ | 0.91–0.93 Rasch analysis conducted, Unidimensional | Reproducibility: 0.91 | Literature review, qualitative interviews | Pilot study | Correlation with (1) NHP: 0.53–0.80 (2) U-FIS: 0.79 | The QOL in different disease severity patients were significant | Test-retest coefficients were calculated. | Significant differences in CLIQ scores were observed | NA |
 CUCQ | 0.88 | ICC: 0.94 | Review the literature, consultation with patients and experts | Pilot study (20 patients) | Correlation with (1) HBI: 0.38 (2) SCCAI: 0.35 | NA | Test-retest coefficients were calculated. | Correlations with EQ5D (r = 0.58), SF-12 (0.63 and 0.65) | (1) Sensitivity to change (P < 0.05) (2)Responsiveness ratio: 0.64 (3) standardized response mean: 0.89 |