Darsee JR, 1978, USA | 108 consecutive patients presenting to CCU | Questionnaire | Belching as a symptom in patients with confirmed inferior myocardial infarction | Sensitivity 69%, specificity 84% (no p value given) | Possible bias from direct questioning. |
Logan RL et al, 1986, NZ | 227 consecutive patients presenting to CCU | Questionnaire | Belching as a symptom in patients with confirmed cardiac ischaemia | Positive predictive value of 72% (no p value given) | Possible bias from population chosen, that is, CCU admissions. |