Table 4

Acceptability, reliability and tests of scaling assumptions for CROQ-CABG and CROQ-PCI

Range of scoresAcceptabilityInternal consistencyTests of scaling assumptions
CROQ scaleScaleSample% missing% floor/% ceilingnCronbach's αMean item-total correlation% definite scaling success (% probable scaling success)
CABG prerevascularisation (N=2685)
 Symptoms0–1000–1002.30.3/5.526220.870.65100 (0)
 Physical functioning0–1000–1002.12.0/10.926280.910.71100 (0)
 Psychosocial functioning0–1000–1001.20.1/1.526530.940.72100 (0)
 Cognitive functioning0–1000–1001.21.5/30.026540.900.79100 (0)
PCI prerevascularisation (N=3711)
 Symptoms0–1000–1002.60.3/4.236160.890.69100 (0)
 Physical functioning0–1000–1002.13.7/10.036320.920.74100 (0)
 Psychosocial functioning0–1000–1001.20.5/1.736650.950.74100 (0)
 Cognitive functioning0–1000–1001.21.8/28.436670.910.81100 (0)
CABG postrevascularisation (N=869)
 Symptoms0–1006–1002.20.0/33.18500.880.67100 (0)
 Physical functioning0–1000–1002.00.7/39.88520.930.76100 (0)
 Psychosocial functioning0–1000–1000.50.1/13.28650.960.77100 (0)
 Cognitive functioning0–1000–1000.60.3/41.48640.910.82100 (0)
 Adverse effects0–1000–1000.60.1/13.18640.860.56100 (0)
 Satisfaction0–1000–1000.10.1/33.38680.790.57100 (0)
PCI postrevascularisation (N=837)
 Symptoms0–1000–1002.60.1/23.48150.910.73100 (0)
 Physical functioning0–1000–1002.41.4/35.58170.940.80100 (0)
 Psychosocial functioning0–1005–1000.50.0/11.08330.960.7893 (7)
 Cognitive functioning0–1000–1000.80.6/36.98300.900.80100 (0)
 Adverse effects0–1000–1001.30.1/70.38260.840.62100 (0)
 Satisfaction0–1000–1000.20.5/26.98350.830.61100 (0)
  • CABG, coronary artery bypass surgery; CROQ, Coronary Revascularisation Outcome Questionnaire; PCI, percutaneous coronary intervention.