Analysis of longitudinal changes in dyspnea of patients with chronic obstructive pulmonary disease: an observational study

Table 2 Correlation coefficients between the changes in different dyspnea measurements

	OCD (/year)	mMRC (/year)	CRQ dyspnea (/year)	SGRQ activity (/year)	Borg score (/year)
OCD (/year)	1
mMRC (/year)	-0.51*	1
CRQ dyspnea (/year)	0.45*	-0.49*	1
SGRQ activity (/year)	-0.52*	0.52*	-0.52*	1
Borg score (/year)	-0.06	0.04	-0.10	0.02	1

* p < 0.001. OCD Oxygen Cost Diagram, mMRC modified Medical Research Council dyspnea scale, CRQ Chronic Respiratory Disease Questionnaire, SGRQ St. George’s Respiratory Questionnaire.

ISSN: 1465-993X