Table 3.

Concurrent validity of SGRQ-I

	SGRQ-I Total	SGRQ-I Symptoms	SGRQ-I Activities	SGRQ-I Impacts
K-BILD total	−0.76*	− 0.58*	− 0.71*	−0.70*
K-BILD chest symptoms	−0.69*	−0.64*	− 0.54*	−0.66*
K-BILD breathlessness and activities	−0.78*	−0.57*	− 0.76*	−0.70*
K-BILD psychological	−0.58*	−0.47*	− 0.52*	−0.55*
SOBQ total	0.80*	0.54*	0.74*	0.76*
SF-36 PCS	−0.71*	− 0.50*	−0.63*	− 0.68*
SF-36 MCS	−0.46*	− 0.40*	−0.34*	− 0.46*
FVC%	−0.30*	− 0.32*	−0.20*	− 0.30*
DLCO%	−0.48*	− 0.28*	−0.53*	− 0.42*
6MWD (m)	−0.50*	− 0.25*	−0.46*	− 0.52*

All data are presented as Pearson’s correlation coefficients for all patients. *: p < 0.02. SGRQ-I: IPF-specific version of the St. George’s Respiratory Questionnaire; K-BILD: King’s Brief Interstitial Lung Disease questionnaire; SOBQ: University of California, San Diego Shortness of Breath Questionnaire; SF-36: Short Form-36; PCS: Physical Component Score; MCS: Mental Component Score; FVC: Forced vital capacity; DLCO: Diffusing capacity of the lung for carbon monoxide; 6MWD: Distance walked during the 6-min walk test