Table 5.

Results of nominal and numerical correlation

	Nominal correlation			Numerical correlation
	RFS	RSI	RGE	RFS	RSI
AET (%)	NS	NS	P < 0.001	NS	NS
Total reflux number	NS	NS	P < 0.001	NS	NS
Acid reflux number	NS	NS	P < 0.05	NS	NS
Non-acid reflux number	NS	NS	P < 0.05	NS	NS
Proximal reflux number	NS	NS	P < 0.04	NS	NS
SAP	NS	NS	P < 0.009	NS	NS
Gas refluxes	P = 0.028	NS	NS	P = 0.026	NS
Upper endoscopy	NS	P < 0.001	P = 0.009	NS	NS
MII-pH (diagnosis)	NS	NS	P < 0.001	NS	NS

RFS: Reflux finding score; RSI: Reflux symptom index; RGE: Gastroesophageal reflux diagnosis; AET: Acid exposure time; NS: Not statistically significant; MII-pH: Multichannel intraluminal impedance and pH; SAP: Symptom association probability.